Yuba Mundo "Spike" Special

Bike Arrival


This bike belongs to young gentleman by the name of Spike. A very interesting person with a very interesting bike. First impression is that this bike has been carefully and competently modified. Also, it has been cared for to the point it needs no work don to make it ready for the powerful Bafang motor. 

However, first step means thorough cleaning. Notice the electronics on the front wheel. Very interesting... as  the wheel spins it lights up and displays a beautiful picture. The front wheel is removed prior to cleaning and cleaned independently.

When bikes like this arrive for conversion my first thought is "How am I going to test ride this with those massive bars?"

On the stand


We have special bike lifts that we use on heavy bikes. Here is one of our technicians working on the standard work stand and performing the second level of cleaning and inspection. As an aside you can see blue tape on the back rest of the bike. Every bike that comes into one of our locations has a name attached for identification, and a box for take off parts is labeled to match the bikes. 

Again, this bike is in great condition and cleaning and inspection shows this bike will make a great eBike.

Installing the motor


This is when the bike is moved to our heavy lift bike stand. The bike with the motor, and soon to be added battery, is a bit much to use a standard work stand. The motor was installed without the use of a single spacer on the motor...a perfect 68mm bottom bracket shell. We noticed during the installation of the motor that the bottom bracket shell was spotless! No rust and no debris of any kind. As I mentioned prior...this is a well cared for bike.

****By the way***

I do not sing the praises of a clients bikes. When we find things missing, damaged, or a product of poor craftsmanship we point it out. The reason we do this is there are many people who read these conversion accounts and it is helpful to all who are doing, or who are considering, their own conversion.

Installation of motor brace


Notice the backward hat of this technician. Time to get serious as we prepare the bike for the motor brace. A motor brace is required on all steel framed bikes, and on all bikes that will have a BBSHD 1000 watt motor. If you omit this step your motor will eventually work itself free. A Bafang motor is held in place by a steel fixing plate with serrated edges. This plate is pressed into the aluminum bottom bracket shell and holds very well is your bike has an aluminum frame. If your bike has a steel frame, it is not possible to press the steel fixing plate into a bottom bracket to the degree it will hold the motor in place for any length of time. Also, the Bafang 1000 watt motor to too powerful to fit on any bike without a motor brace.

To install a motor brace we drill a small hold and install a Rivnut in the frame. The motor brace attaches to the motor and then is held in place by the Rivnut.

Test Ride


Today is the day for the test ride. On the bike...battery on...display on...all looks good....hit the throttle to get it moving...nothing! A little embarrassing as a crowd had gathered around as the bike draws a lot of attention. We pushed the bike back in the shop and began to look at the first thing you always examine when you have power but no motor response...the brake cutoff.

On this bike I chose to use the Hayes in-line cut off device instead of the standard Bafang brake lever with cut-off. This was done because of the massive bars and the cable on the Bafang cut off is to short.

Verdict...yes it was the brake cut-off. We ended up installing the Bafang standard.

Test ride two: Battery on....display on...hit the throttle....Awesome bike awesome ride!

Finished Bike


This bike rides much better than you would expect. It shows the owner modified this bike knowing what he was doing. I was very impressed and my only regret is I could not spend more time cruising Alameda on this bike...might give my much needed street cred a boost!

Trek 830

1999 Trek 830


This is a 1999 Trek 830 that belongs to our new Intern, Ryan from Alameda High School. Ryan is a very astute, intelligent young man who is a quick learner. The bike he will be working on is his own. Ryan begins with the way we begin all bikes at Island City and that is the initial cleaning of the bike.

Trek 830 1999


This is picture of the bike as it appeared in 1999. It was a well made bike with mid range components on a very good aluminum frame. This bike retailed for $440 in 1999. At todays price that would be around $700. As you can see it was a very good bike in its day.

When Ryan first brought his bike in I could tell it had been used often. It needed a lot of work. However, all 20 year old bikes should reflect the wear of 20 years! Bikes are made to be ridden and enjoyed. The more we ride a bike the more it will reflect such use.

On the stand


Here you can see Ryan has already removed the cables, wheels, pedals, crank arms, front derailleur, rear derailleur, and bottom bracket. Now he is removing any rusty bolts that are on the bike. Next, he will be removing the twist shifter and replacing it with index shifting. Ryan's task is to rebuild the bike using modern components.



Ryan is becoming acquainted with the tools that are unique to a bike shop and that are necessary for safe removal and installation of parts. Ryan is install a new 68mm bottom bracket. We were going to use a Octalink crankset but it did not fit well in this older shell. As Ryan begins the process of removing the crankset he begins with a "clean out" tool. This small tool is very important and should not be overlooked. This tool will "clean out" all debris and straighten out any threads. It will make using the crank puller much easier. It is easy to strip these threads so it is important to prep the threads before using a crank puller. 

Removing the chain ring


This tool is a crank puller. There are different types of crank pullers and this one is the correct tool for an Octalink crank. Now that the threads have been cleaned out Ryan begins to slowly thread the crank puller as far as it can go. It must be tight against the axle before attempting to remove. If it not tight, put a crescent wrench on it and tighten until it stops. Now, Ryan begins to turn the handle clockwise until it begins to get difficult to turn. Ryan continues to turn the handle until, finally, it begins to move and the whole chain ring comes free. Ryan repeats this process on the other side. Next, we will put a 68mm square tapered spindle bottom bracket on with either a double or a triple chain ring.

Bottom bracket installation


coming soon

Ghost Lanao

Arrival of the Ghost Lanao


This is a Ghost Lanao bike from REI. REI is now carrying their own line of bikes and this is a very good example of their offerings. It is an excellent bike with all the right features at a great price. However, as soon as I saw the bike I knew it was going to be a difficult build. First, it is a very small frame. Small frames means battery placement problems. Second, it has a double up front but a huge cassette on the back which always signals chainline challenges. But, we welcome challenges and was looking forward to this build.

On the stand


Here you can see how we have placed the motor. It was not easy because of all the cables that were running in the path of the motor. The shift cable we were able to manipulate to an area where it would be unimpeded.  It is VERY important the shift cable be unimpeded! If it is crimped by the motor it will never downshift properly. The hydraulic line to the brakes we had to reroute entirely. The whole process was not too difficult...compared to the battery.

Battery placement


Perfect! Putting a battery on the top of a top tube is one of the most difficult processes in battery placement. You get one chance to drill for the Rivnuts. You measure, measure some more and then measure one more time. Then you start with a pilot hole and then measure again. If the holes are not straight the battery placement will look terrible and you cannot re-drill the holes! When I say it came out perfect it was because it took a very long time and the result was exactly what we were aiming for. 



Oddly enough, it is the stock chainring that allowed us to get the chainline spot on. Not only was the chainline perfect but we were also able to use the entire range of the rear cassette. Often, when a bike is a "one by" it is not possible to use the full range so you have to use the limit screws to lock out the last two (or three) cogs. A "one by" means there is one very small chain ring up front and a massive set of cogs on the back. It is the size of those cogs that make for a very wide chainline. Works fine under human power, but not under the power of a 750 Bafang Mid drive. Therefore it is often necessary to lock out the lowest gears. In this case...not a problem with the stock chainring. Every bike is different and requires its own set of rules to be converted into an electric bike.

Test Ride


uh oh...small bike is very difficult to test ride...so I had my associate take it for a test ride. When she returned she had a smile on her face and said, "Wow!" It is a beautiful bike and a great electric bike. When the owner picked it up I told him; "This bike is finished, but it is not finished until your wife says it is finished." "If there is anything she does not like...bring it back and we will change it." I meet the nicest people in this line of work.

Finished Bike


Beautiful bike and I hope she likes it!

Cycle Truck Cargo Bike

Cycle Truck Cargo Bike


This is a bike called the Cycle Truck. I think it is a great small/midsize cargo bike and will be a great candidate for a conversion to an eBike. As we prep it for the first cleaning we do not see a single thing that would need attention. It is a well cared for bicycle.

Scrub time...


This first step is always the most interesting. One of recent employees was told part of her duties is to clean the bikes. She glanced up briefly as if to inquire why she should clean bikes. Of all the bike shops she has worked as a mechanic the process was, "If a bike came in dirty it left dirty." I explained to her that cleaning a bike, in order to prepare it for conversion, is one of the most important steps as it allows us to inspect for any fault that might make conversion to an electric bike unsafe.

These are the things we look for


This bottom bracket shows rust and that means there is rust in the frame. What we do at this point is we look for any obvious points of intrusion. We also look for any blocked drain orifices. The we lean out the bottom bracket shell, spray WD40 inside the frame, and apply a heavy treatment of grease to act as a barrier. 

The bottom bracket shell


No, we do not shove a motor into this shell knowing the owner would never know the difference. It is cleaned and treated as it should be. What would happen were the motor forced in and finished? The rust would eventually bind to the motor and it would become seized. A process that can happen fairly quickly. The result would be the motor could never be removed. One of the benefits of the Bafng mid drive motor is that it can be removed and put on another bike if one so desires.

On the stand


One on the stand we go through our second cleaning and inspection. In this case we see that the rust was only limited to the bottom bracket area and the bottom bracket shell itself seems to be in good shape. As a prophylactic, we liberally apply grease prior to the installation of the motor. Prior to the installation of grease, an inspection is made of all drain holes in the frame. All looks in great shape.

Motor brace installation


This is a motor brace. It is pointless to install a powerful Bafang motor on any steel framed bike without a motor brace. A motor brace is essential on any bike with the 1000 watt motor, and all steel or titanium framed bikes. If this motor brace is not used the motor will eventually work itself free. It is not required on any build that uses a 750 watt motor and an aluminum frame. Why is this? A Bafang motor is held in place by a serrated fixing plate made of steel. This plate is pressed into the bottom bracket. If the bottom bracket is aluminum, the steel plate being of harder material, works very well. However, if the frame is made of the steel it is impossible to press the steel fixing place into the steel bottom bracket shell. Thus, the motor will eventually come loose.

Cycle Truck Continued

Motor Installation


When we lock down our motors we use a pneumatic impact driver. We do this for two very important reasons. First, and always first, is safety. THe typical method of tightening the M33 nut is to take a wrench, attach a long "cheater bar" and pull as hard as one can. The problem with this method is...one slip and one may end up in the hospital with injury. The other reason why we use a impact wrench is that we never want a single motor to come loose.

Battery placement


This is a picture of the finished bike with the battery in place. Some bikes, like this one, battery placement is very difficult. We were able to place a full sized 48v 13Ah battery on the downtube but the distance between the battery and the chain is about 2mm. We locked it down very tight and it should not move. I told the owner of the bike that if the battery ever moves and the chain begins to rub on the battery we will provide a remedy. This type of warranty is for the life of the bike. 

Finished Bike


Looks like the same picture! Yes, it is. This bike was very challenging to build but it was also very rewarding as we solved puzzle after puzzle. We located the reason there was rust on the bottom bracket and addressed the issues. There was a missing spacer that would not allow the highest cog to to be used. We replaced the spacer.  A lot of time was spent searching for a suitable combination of front chainring and rear cassette that would allow the clearance we needed for the battery. The final product was a build to be proud of. Not to sound our own horn but that was the goal when we began this particular build.

Test Ride


When I rode this bike one of the first things I noticed is how well it tracks. More cargo bikes are more stable and track better than any other bike. This is a small cargo bike but like its bigger cousins it also tracks very well and is a very stable bike. The throttle is very responsive. We use a heavy duty throttle on all our build as it seems to be much more durable and seems to work better. This build took many hours beyond what we had planned but the final result made it worth all that extra time.


Cycle truck cargo bike made in the USA

This is a fantastic small cargo bike made in Northern California by an independent fabricator. I was very impressed with this bike and when completely finished with a Bafang 750 watt motor it ran like a charm. If you are interested in purchasing this bike you may contact the builders from their website at www.cycletrucks.com

Ok...that was fun. What's Next?


Dang it's hot...let's get building!

BMC Team Elite 03

BMC Mountain Bike


This  bike came in today and it is absolutely beautiful. I put it up on the stand and called my assistant over and "looks pretty cut and dry right?" This bike is in like new condition and I only say "like new" because the only bike that is new is fresh out of the box. However, this bike was pretty close. As with all bikes that come into our shop we start with the cleaning process.

Cleaning the bike


Remember, this bike is going to converted into an electric bike using a very powerful motor. Inspection is essential.

What are we looking for on a bike that is obviously new? When we take the thru axel from the wheels we inspect them to insure they have been greased. Often, that is overlooked. In this case both thru axels were liberally coated with grease. When we removed the pedals we inspected to insure they were greased (usually they are not). These pedal were greased with a high grade grease. Then we clean the wheels and tires. The wheels we check each spoke. This bike is in fantastic condition and all evidence points to having been built by very competent and conscientious individuals.

On the stand


Sorry for the poor lighting. Here on the stand we get our first look at the frame. We are looking for any cracks, fractures, poor welds, misaligned hangers, or anything we might think would make the bike unsafe to ride under power. This frame has great welds, and will make a great eBike. That said, never assume something is not waiting around the corner. 

Installing the motor


Installing the motor went without any difficulties. Notice the motor brace that we use. We will use a motor brace on all steel frames and on all bikes that have a 1000 watt motor. If you do not use a motor brace the motor will eventually come loose and spin in the bottom bracket shell. With a motor brace the motor will stay put. 

Unique Difficulties


Cable and loom management. What does one do with all the wires and cables that are a part of the Bafang motor system? If I see a bike in the shop and I do not like the wiring then we do it again. There is no system that might make it easier because bikes vary in size, shape, and even color. An all black bike is easer to wire than an all what bike. Last night I spent 2 hours on the wiring. It was worth it. Some of the wires a cables we shorten then splice them together. Other cables have 7 very thin wires inside the cable and it would be cost prohibitive to reduce and splice.



Trouble...on the test ride the shifting wash very harsh. Immediately I knew something was not functioning as it should. I dismounted and walked back to the shop. I put the bike on the stand and engaged the motor and watched as it began to go through the gears. The problem was obvious; The gear sensor was not working. There was power to the sensor, the green light was flashing, but the red indicator light was absent. This gear sensor was non functional. An hour later, a new gear sensor and the bike performed flawlessly. This is the first faulty gear sensor I have seen. There  are no perfect production lines and sooner or later one will find a lemon among the apples.

Santa Cruz Tall Boy

Full Suspension


This a a full suspension bike and if you have never converted a bike like this before it is recommended that you hire a qualified bike mechanic with experience in working with eBike conversions. This is a very good bike and the owner is an experienced rider. These are two important factors. One of the first question to ask is, "Where do you put the battery?" In this case, it cannot go on the bottom of the downtube as there is no room for the suspension to compress. We decided to put the battery on the top tube. The top tube works because it has a flat surface for better mounting and the material is thick. 

Cleaning the bike


The first cleaning we pay attention to large items that need attendance, smaller items come later. When on the bike we noticed the rear derailleur was making a snapping noise. That almost always indicates the clutch on the derailleur has failed. Otherwise the bike is in very good condition and well cared for.

The rear derailleur


We were hoping after through cleaning the problem world be resolved. After each part and been completely removed of all debris and lubricated the problem persists. Tomorrow we will look at the clutch mechanism. It might be noted even though this problem persists the derailleur seems to work fine. However, if it will work  under the power of a 750 watt motor is to be seen. That is why we do not simply toss a motor and a battery on a bike and say "Thanks," and send you on your way.

On the stand


IF you look closely at the bottom bracket shell you will see welded a bash guard bracket. This must be removed in order to insert the motor. Upon beginning our goal was to remove as much material without coming into contact with the welds. We knew when we began it would be along process of filing by hand. If this is not done correctly the motor will not roll into it highest position and can be in danger of sitting crooked in the bottom bracket shell.

Slow...but sure


This is a picture giving you an idea of the material that has to be carefully removed. We could have chosen power tools to remove this material but decided to use a file instead. It took 3 hours filing but when we finished there were no welds affected and the motor went into the bottom bracket all the way without any contact. The true test is when we roll the motor forward until the bottom of the case is in contact with the downtube. 

Finished Bike


This was one of our more difficult builds but in the end everything worked out fine. One of the difficulties of converting a full suspension bike to electric is cabling. A lot of things are in motion while riding a full suspension bike. Therefore, all cables have to be positioned in such manner that they do not come in contact with anything moving. Also, the shocks have to be adjusted to handle the initial power of the Bafang motor.

So far, no two full suspension bikes we have converted have been the same. They are challenging, difficult, and interesting to convert. We hope to see more bikes like these in the future.

Xtracycle Swoop

The Bike


This is a beautiful example of the Xtracycle Swoop. Xtracyle has put a lot of thought into their design. For example, the use of the 20 inch rear wheel to lower the cargo area, the easy entry, and the lightweight frame of high grade steel. 

This bike will be retrofitted with a Bafang BBS02 750 watt motor and a 48v 13Ah battery.

Getting ready for cleaning


Cleaning means inspection. This bike is in near new condition and cleaning was a breeze except the rear derailleur. Rear derailleurs are a magnet for grime and grease. They always have to be removed from the bike and cleaned independently.

Now, look at the picture above. This is on the Hooptie rail and was also on the side runners. These are "limit lines" and one should NEVER see them on any bicycle. When parts are assembled these are guides to indicate  the minimum insertion point. If you can see the marks then it is unwise to use.  Any part on any bike can fail if the part is not inserted past the minimum insertion line. Why were these visible?

When this bike was originally built the put the parts on backwards. 

Correct Assembly


The above picture shows the side runners on correctly. See how beautiful the parallel lines are? This was a difficult correction and may hav been why they were on incorrectly. In order to remove the side runners, there is a small screw being blocked by the kickstand. The kick stand had to be removed to get access to the bolt. The whole process took about an hour.

Eventually, a child would have stepped on that rail and it would have snapped off. All bike builders are aware of "minimum insertion lines" and always respect their meaning. They are found on seat posts, stems, and a variety other places. They are there for safety, not for the preservation ff the part.

On the work stand


When a bike is on the work stand we begin the process of the second cleaning. Here we can see the frame and fork clearly. We are looking for any hairline cracks, misaligned hangers, loose connectors, or anything that might make a conversion to an electric bike unsafe. This bike is almost new and is in great condition. One of the few that will not require new brake pads. 

Time for the motor


Having installed hundreds of Bafang mid drive motors one would think it is an easy task. Every bike is different! This bike, for example, has a hydraulic brake line and the rear shifter cable running right in the path where we will be placing the motor. The motor cannot sit on the hydraulic line. Therefore, we use a motor brace that allows us to set the motor in a position that frees the hydraulic line.

The Battery


A eBike is just a bike without the battery. The battery is the most important part of any electric bike. I am very fortunate to work with a battery manufacturer overseas that make the absolute best battery. I have never had a single battery fail.

Recently we switched model SO39-3 for Model RO49-2 and are very pleased as are our clients. The picture above is the new RO49-2 battery base plate. When this plate is installed correctly the battery slips on and off easily. The old model was very difficult to remove.  We install the base plate on top of an aluminum base plate attached with stainless steel screws and highly rust resistant coated washers. 

Xtracycle Swoop Continued

Wiring the battery


We wire the motor and battery using Anderson Power pole connectors. We do not do this because they are inexpensive. On the contrary they are the most expensive method of connecting the power source to the motor. Not only are they costly but it requires special tools and experience to use them correctly. We use them because they do not fail. They provide a reliable connection between the battery and the motor and to this day not a single one has failed.



Grease, it is messy and is never easy to apply. I think that is why so many decide to omit this step. But consider that I am inserting an aluminum tube into a steel frame. The result of this will be an exchange of ions between the two materials resulting in galvanic corrosion. The only way it can be prevented is creating a barrier between the two metals. The application of grease is what creates the barrier. This is why we use grease, not that it will slide in easier, but because it will preserve the life of the bike. 

Almost finsihed


The bike is nearly finished and tomorrow will be the first test ride. I shortened the top bars and I did the running boards on the bottom. Everything is almost complete/ Looking forward to the test ride. I test ride a lot of cargo bikes and they are quite a bit different than standard bike. Due to their length the track very well and almost feel like an electric motorcycle. 

Test Ride


This bike rides very smoothly. It is a perfect balance between weight and power. The length of the bike provides that sense of smoothness, as if you are on a motorcycle. It is very responsive to the throttle making it a pleasure to ride using the throttle alone. I cannot say that about all cargo bikes. This is one of the lightest steel framed bikes on the market. My mechanic picked up a magnet to see if it was aluminum or steel as he thought it too light for steel. 



While in our shop several people ask "how much am I selling the Xtracycle?" To which I replied, "Sorry, it is for a client." It was a beautiful bike and now is a beautiful eBike. This is a bike that will carry small children. I never lost sight of that fact while cleaning, inspecting, tightening, building, checking, testing, and testing again. It means something when a family places their bicycle under our stewardship. I never lose sight of that fact and if I ever do then I have finally reached the age of mandatory retirement. 

Up next?


coming soon

Yuba Mundo Bionx Model

Bike arrival...


This a Yuba Mundo Cargo bike with a Bionx hub motor system. We have done quite a lot of Yuba conversions and a few of those are the Bionx model. As it is well known, the Bionx company went out of business leaving all their customers without access to service or batteries. Their batteries are proprietary and cannot use any other batteries except their own....which there are none. The batteries we use are not proprietary and can be moved from bike to bike.

At first glance the bike seems well cared for and no obvious issues. The owner pointed out a spot that had been welded. Our frame builder and welder will take a close look to see if it has been done correctly and has not compromised the integrity of the frame. Next up....first cleaning

Cleaning the bike


A gentleman ask the other day if I could lower the price as his bike does not need cleaning. I replied, "We do not charge for cleaning, it is part of the process." It is only through cleaning are we 100% certain of the safety of the bike. Remember, we are converting this bike into an electric bike using a very powerful motor. 

As you can see, we inspect everything. Notice all fabric material is removed; cargo bags, basket liner, and child seat. These are placed in a container and washed with soap and water. What does that have to do with safety? Nothing at all. We do this because it makes no sense to install anything on a bike after the conversion that is not as clean as everything else. 

Look what we found...


As part of the cleaning process, we remove the cassette in order to clean each cog and the cassette housing. When I removed the cassette this fell into my hands. What is it? A cog spacer? No, it is a spacer that goes behind the cassette. That means this is not a 7 speed hub. It is a 7/8 speed hub! Next I checked his Sram X4 derailleur. Yep...a 7,8,9 derailleur. So I removed the completely inadequate 12X28 7 speed cassette and replaced it with a 11X34 8 speed cassette. This is a big improvement as it will give the bike much better climbing ability and better shifting.

This is one of the bonuses of cleaning everything. Had I not removed the rear cassette for cleaning I would not have discovered that small spacer.

Why we remove the derailleur


You cannot properly clean or lubricate a derailleur when it is on a bike. A derailleur has 9 pivot points  all of which needs lubrication. If a derailleur is on a bike these 9 points cannot be reached. Also, a derailleur has two pulley wheels that invariably attract all kinds of string, weeds, lines of all sort, and even hair that winds itself into the small races of the pulley. With tweezers I pull them free, other times I have to dissemble the pulley wheels. However, these small wheels have to run smooth and free to carry the chain.

Note to Builders......


See that sharp edge on that zip tie....it is completely irresponsible of any builder of a any bike to leave a knife sharp edge on any part of the bike for any reason. I instruct my mechanics to remove all zip ties from bikes and reinstall with our own. There is a small tool called "side cutters," or "flush cutters," that cleanly snip a zip tie at its base. It is not that much work and it is negligent to do otherwise. Buy a flush cutter, use it. Next time it will be  a child's hand that is injured.

On the work stand


This is where it goes through the second step of cleaning. Our welder examines the welding around the kickstand and confirms it has been done by brazing, not welding.  Brazing uses a filler (in this case brass) at a lower temperature than would effect the steel of the frame. While the brazing is fine, the paint touch up was a bit off but we limited as to what could be done.

Yuba Mundo...Continued

Installing the motor


Here we have installed the battery base plate and are installing the motor. If you look closely you will see we have added a motor stabilizer. The motor stabilizer is required on all 1000 watt motors. This motor is simply too powerful and will eventually work itself loose without a motor brace. Most builders will not use the brace (cost involved) as they feel it can be lock in place tight enough. While it is true it can be locked down tight enough and may not come loose for a week, month, maybe it year....but it will work it way free and begin to rotate in the bottom bracket shell. Our motor will never come loose and that is why we use it. 

Mmmmm....front tire


The back tire on this bike was fine, in fact great. But the front tire is a stock tire that costs us about $8. First, it is inadequate for any bike, much less a cargo bike, and it certainly is not recommended fo a bike that can exceed 28MPH.

We replaced this tire with the Schwalbe Marathon GT+ ebike rated tire. In order for the front tire to match the rear tire we replace the rear also.

Disc brake pads...


Obviously this one needs to be replaced but often we see pads that have 50% life left. On a cargo bike, as a minimum ,we always replace the rear brake pads, regardless of condition. We do this because any maintenance on a cargo bike is very difficult. To replace the disc pads, the wheel has to be removed and that requires removal of cargo bags, and wheel covers. Brake pad maintenance is often neglected because it is difficult to reach the adjustment mechanism. That is why we provide fresh brake pads on all of our conversions. 

Let me correct myself, if a brake pad is in new or 90% new condition we do not replace. However, we see very few in that condition.

Professional Ethical Dilemma


What to do when a bike owner has ordered parts and services for the conversion of his/her bike and yet you know to build the bike correctly requires certain additional parts in order to cause it to perform correctly. I have seen two approaches to this problem. The first is "the hell with it, give them what they paid for. I do not say that in jest.

The second approach is the one we use and that requires paying out of our pocket at times. I would be embarrassed to turn out a product that I know will fail. On this bike I know a Lekkie chainring will be needed to help hold the chain in place and we have to use a chain guide and tensioner to keep the chain tight. 

Out of all the bikes we have converted to eBikes (getting close to 400) we have had only a few where the chain would fall off. Of these few we had them returned and corrected the problem at no charge.

Finished Bike


This bike is finished but not quite. There remains a few minor adjustments. If you look close you will notice a Lekkie chainring up front. These are special chainrings that are designed to keep a chain from falling off the chainring. As often pointed out, the powerful Bafang mid drive motor  will exploit any deviation in a bike where human power cannot. A chain line can be off under human power and nothing will happen. If that same deviation is present under the power of the Bafang mid drive, it will cause the chain to "drop off." The Lekkie, with its narrow/wide tooth pattern, holds the chain firmly. If you look at a bike chain you will see a "big space" and a "narrow space" in the links.. A narrow /wide tooth chainring fits in its corresponding space and that is why narrow/chainrings are so effective.

Test ride...


Powerful. On a test ride we not only are checking power, shifting, handling, and brakes but we are also listening. Listening very closely. We have tested hundreds of Bafang equipped bikes and know every possible sound to expect. It is when we hear a sound we are not familiar with that we stop the bike and return it to the shop and back on the work stand. Usually it is something like fender rub (common), chain slap, spoke reflector (very common), or anything that is attached to the bike. It is very important it be identified. 

Today after some minor adjustments the owner will be notified that the bike is ready to ride.

Surly Big Dummy Cargo Bike

Arrival of the Bike


This is a picture of the Surly Big Dummy long tail cargo bike as it arrived at our shop. We will be converting this bike into an electric cargo bike. First glance reveals what we like to see in a bike. It has been well used and it has been well cared for. Bikes are made to be ridden and enjoyed and not to be stored away. All of us who work on bikes know that a bike that is never used always has its problems.

First I notice the dust. What kind of dust is it? If it is "Burning Man" dust then I know it will very difficult to remove, if at all. Fortunately it was common dust and not the highly alkaline dust found at Burning Man. Secondly, I notice all the expensive components on this bike. Surly sells this bike as a frameset and it looks like someone built a very nice cargo bike. 

Cleaning the Side Bags


We start by removing the cargo bags and washing them in soap and water. First we hose them down, inside and out, then we place them in a 5 gallon bucket and wash them until clean of all matter. Why do we do this? Because that is what we would do if it were our bike and every bike we work on we keep that thought in mind. For

example..."would I put that chain on my bike," "would I put that disc brake rotor on my bike," "would I put those tires on my bike?" 

These bags cleaned up nice. When I took the cover off the padded seat I found the cushion itself was made of very fine rubber. Much better than what I find on most (all) other cargo bikes. The cushion was easy to clean. 

Underneath the cushion was the top board. This top board is in mint condition! It looks great and was preserved having been covered by the seat cushion.

Cleaning the Bike


The process begins with the initial cleaning. There will be 3 stages of cleaning before we are finished with the build. Cleaning a bike tells us everything we need to know about a bike, its true condition, and wether it is a candidate for conversion to an electric bike. If, at any time in the process we discover a fault in the bike that an electric motor can exploit, making it unsafe, the bike is reassembled, tuned up and returned to the owner at no cost.

It was cold outside and the wind was up but  I continued to clean this bike until it was ready to give up its secrets.

For the first year of this business I worked at home, in the dining room with my little dog at my feet. My gracious wife had one rule, "No dirty bikes in the house." That was when I began to clean bikes and that was when I would discover hairline fractures in the frame, bad bearing cups, loose  or missing parts, cracked spoke eyelets, and many more. Now, no bike that enters our shop for conversion is exempt from this necessary step.

Discovery - Tube


This is what happens when you brake hard with under inflated tires. The tire moves on the rim pulling the tube with it. This has to be corrected for if left to itself it will result in a blowout. When we pull the tire off we will inspect the rim tape to insure it is in place.

Let's Talk Tires


Sorry for the same picture but here you see the tires. These tires are awesome and I told our client they would not need to replaced. Why would we as the were rugged Schwalbe tires with plenty of tread. After I finished cleaning them I walked to my computer to look up the tires. I discovered the tires were discontinued around 2009. Are they still usable? I do not think they should be used on any bike that is to be ridden on the road. An electric cargo bike with a full load is still capable of speeds over 25MPH and therefore have to the very best tires in the very best condition.

On the Stand


Here we do our final inspection and the second round of cleaning. Everything looks fine and the frameset is in great shape. What we did discover was the rear derailleur and the shifter were worn to the point they will need to be replaced. If we had not removed the derailleur from the bike we would not have discovered the bearings in the upper pulley wheel were completely gone. This bike never would have shifted correctly under this condition. It is time to replace the derailleur and shifter. This is a great bike and it is worth installing a new drive train to make it a great bike for years to come.

Surly Big Dummy Cargo Bike

What's Up With the Grease?


This picture is of the running board rails we are getting ready to install. That slimy looking stuff is a high grade grease made by Phil Wood. We often find the application of grease on metal to metal parts has been overlooked resulting in premature wear and corrosion. In bicycle maintenance one should always disassemble, grease and reassemble certain parts of the bike to insure the bike will last for years.

Grease is important in the assembly of the tubes on any cargo bike as it creates a barrier between the two metals that will reduce friction, and protect against rust. When this bike was disassembled we noticed very little rust. The absence of rust indicated this bike was assembled properly when initially built.

The failure to use grease will lead to parts becoming "seized" and when that happens the bike has reached the end of its life cycle.

Time for the Motor


Remember, always insure all cables and lines are not impeded by the motor when installation is complete. Although you cannot see it in this picture, there is a motor brace installed. This has to be done on all bikes with a steel frame. A motor brace does two things. First it can hold a motor in place away from any cables or hydraulic brake lines and secondly it will keep a motor from becoming loose.

This motor was a perfect fit. What did we expect? One never knows. About 25% of the newer bikes brought to our shop for conversion have slightly distorted bottom bracket shells caused by the welding of the tubes. This can always be remedied with the proper tools. By the way, an impeded bottom bracket shell does not impugn the bike brand in any manner as it does not affect the installation of the standard bottom bracket.

The Battery Base Plate


This innocent looking device is the battery cradle, or base plate. A base plate is very difficult to install as it has to meet to meet a very strict criteria. We have many self installers who come to us and say, "I have everything done but I cannot get the battery on." The battery base plate has to be installed in such a manner that it is absolutely flat from the top to the bottom. If there is any rise at any point the battery cannot be seated. In addition, there cannot be any twist from side to side at any point or the battery cannot be seated. So how do you mount a flexible, flat plate on an inflexible round tube? We do not even try. Instead we take 1 1/2" X 3/8 aluminum plate and machine a ridged base plate. In turn, we attach the battery  base plate to our rigid aluminum base plate then attach it to the bike. Now, everything is level, ridged and straight and the battery slips right in. 

Installing U-Tubes


This part is called by different names by different manufacturers but is, more or less, a running board for passengers to rest their feet or to support carry bags. Here is a good example of areas that need grease prior to installation.

This bike is nearly finished. We have upgraded the drive train to the latest model of the Sram GX derailleur, shifter, and cassette. Why the change? First, the derailleur and shifter are worn and needed replacing and all bikes with a very long chain will always work better with a clutch derailleur.  Clutch derailleurs have powerful springs that help keep that very long chain in place. Essential for an electric powered bike with a long chain.

A word About Brake Pads


Almost all mechanical disc brakes have two brake pad adjustment point. There is the outside adjustment point and the inner adjustment point. The inner plate has to be periodically adjusted or it will continue to wear until there is no pad remaining resulting in metal on medal contact. This very common. It is a very simple procedure. You take a Torx wrench and insert it into the center of the brake adjustment dial and you turn it clockwise a couple of clicks. Squeeze the bike lever and see what you have. It is very simple and that is how you keep your brakes working.



We are a shop that prides ourself as having every part on hand for any conversion. That said, there are times when we reach for an item in the stock room and it is not there because the person responsible (our CEO (me)) failed to note the low inventory notice. Result is this build is delayed 24 hours while we wait for a shift sensor extension cable. 

In the meantime we  finish the build as far as we can take it.  

Bike mechanics, as a part of their nature, do not like to remove a bike from the work stand unfinished. It is the way things are properly done in a bike shop and to do otherwise is untenable. It makes sense because all bike repair requires focus. Nothing is routine...ever. Have you ever talked to a mechanic whole he/she is working? First, they never take their eyes or their attention away from their work and second they always indicate they wish the conversation tp be brief...so they can concentrate on their work. 

Surly Big Dummy Cargo Bike

Finishing the Bike


This is the finished bike without the cargo bags and child's padded seat. The new tires arrive today and will be installed. One of the things we look for when a bike comes in is end caps on the handle bars. End caps are a very important safety feature and are are not there for appearance. In every bicycle race an official walks among the racers at the start of the race and he is looking for missing end caps (among other things). If he sees a bike with no end caps he is pulled from the start. We never release a bike from our shop without end caps. 

Test Ride


These bikes are fast with the Bafang 750 watt motor. One last minute change. The initial chainring was a Lekkie 46T. However, the cassette is a 11X34 not a 12X34. This small difference made it difficult to get the bike rolling in high gear. Now, we have changed the chainring, shortened the chain and off on another test.

Perfect! Now, time has come to install the cargo bags and notice the owner.

On Last Note: Cargo Bags


I have installed a lot of different types of cargo bags on a lot of different types of bikes and they can be confusing. I always take pictures before removing the bags. Also, I label them so when it comes time to reinstall it will go quickly.

On this bike I also labels the alumunin tubes "L", "R', "F," and "R". These of course stand for right, left, front, rear. Building bikes is never intuitive. Create a record, label the parts, this will insure you will not assemble backwards. 

Specialized Roll With Xtracycle Leaf

The Bike


If you think you have seen us build with the Specialized Roll as our platform for the Bafang mid drive before, you are correct. The Specialized Roll is our most popular bike as it is very comfortable and is very easy to get both on and off. We are going to take this bike and use the Xtracycle Leaf kit and turn it into a cargo bike. Now, we have done this before and we have taken all we have learned to create the perfect cargo bike.

One of the problems with cargo bikes is that they are difficult to mount when you have children or cargo on the bike. The Roll is a solution to that problem as it has a very low entry. Perfect for a conversion to an electric cargo bike.

The Xtracycle Leaf Kit


I really cannot say enough about this product. When compared with the first generation Xtracycle kit, one finds it is not even the slightest bit similar. The first kit was of aluminum tubes whereas this new kit is made of steel. Yes, it may be a little heavier but as far as durability goes it will last for years. It is very well made. Some cargo bike companies have quality issues. That cannot be said about Xtracycles or their products, including the Leaf Free Radical. When you spend all day building bikes you get used to knowing what is good, very good, and terrible. I rate everything I see from Xtracycle as very good, without exception. I cannot say that for all cargo bike companies. 

On the work stand


Even though this is a new bike everything is removed. The reason for this is we will be upgrading many parts as we build this bike. For example; the tires, rear derailleur, cassette, chain, index shifter, disc brake rotor, cables and cable housing all will be replaced. This bike comes as a 7 speed bike. When we finish it will be a 10 speed electric cargo bike. 

If we like a frame, or frameset, we think it is worth replacing a number of parts on it in order to get that perfect bike. A  7 speed electric bike is very common and is a good place to start. When we build electric cargo bikes we view them a little differently. Foremost in our mind is they are often used to carry children.

The New Derailleur


This is Sram's new derailleur. It is not just a 10 speed derailleur but it is a "clutch derailleur." What a clutch derailleur does is hold the chain under tension while not allowing distortion in the derailleur itself. With cargo bikes the chain is very long and with any long chain it will "bounce" when shifting or just going over bumps. This bounce is magnified under the power of an electric motor and therefore must be eliminated. When a chain begins to bounce it will come off the chainring. Dropped chains are ALWAYS the fault of the builder.  The best way to address this problem is to use a clutch derailleur. This parts costs 4 times the standard derailleur and that is the only reason it is not on all cargo and tandem bikes.

The New Cassette


This the cassette we will be using. It is a Sram GX 11X34 10 speed cassette. The cassette that came with the bike was 12X32 7 speed. This meant the cogs were very far apart which made for rough shifting. The stock cassette is a $12 cassette. When you move to a 10 speed cassette it allows us to have a 11 tooth cog for better top end speed and a large 34 tooth cog for better climbing. Because it is a 10 speed the cogs are spaced close together resulting in smoother shifting.

New Electric Bike Chain


KMC was the first company to make chains specifically for mid drive motors like the Bafang. There is no motor more powerful than the Bafang mid drive motor. The Bafang 750 watt puts out 120Nm of torque and the 1000 watt motor a 160Nm of torque. By way of comparison the largest Bosch  motor puts out 75Nm of torque. 

However, it does not matter how strong the chain is if the bike is not set up correctly. If one has a very strong chain and the bike has been incorrectly built, then any point of weakness will fail. The chain might remain in one piece but the derailleur can be pulled apart, or the wheel pulled from the drops, or even the chainring shattered. The bike has to be built as a whole, not jus a single component.

Specialized Roll Cargo Bike

The Bike


The Specialized Roll Easy Entry is the most requested bike to turn into an electric bike that we receive. It is comfortable, has large tires, is very easy to step into and step out of, and is made of lightweight aluminum. It is a perfect bike to convert into an electric bike. In this buiild we are going to add the Extracycle Leaf kit to turn it into a electric cargo bike! This bike will have a Bafang BBS02 750 watt motor and a 48v 13Ah battery.

The Leaf Kit


This is the extension portion of the lead kit. As you can see this Cargo extension is nothing at all like their first generation kit. This is not made of aluminum tubes but is made to be very strong in every way. We know because we have experience building with both first and second edition kits. The rear wheel comes off the Specialized Roll and the extension goes in place of the rear wheel. It is much more complicated but just give you an idea of how it works. From beginning to end it takes two days to build this cargo bike with the motor and battery installed.

Disassembled and on the Stand


Here we have the Roll stripped down and on the stand. The bottom bracket has been removed and the Xtracycle Leaf has been attached. We also have removed the rear derailleur that comes with the bike and have replaced it with a Shimano Claris derailleur. We do this because the Claris is a much finer derailleur, has stronger springs, and is generally a higher quality derailleur.  We aso remove the 11x28 stock cassette and replace it with a higher grade 12X32. We think the 32 tooth cassette gives this bike better climbing under a load. We also  remove the 7.1 pin chain and replace it with  heavy duty 7.3 pin chain. This is a cargo bike so the drive train will be under power while carrying a load.

Chain Tension


One of the challenges of building any cargo bike is chain stabilization. A cargo bike chain under human power has a tendency to come into contact with the bikes chainstay and even the tires. Sometimes a chain will bounce off. Under the power of an electric motor this problem is exacerbated. Therefore each cargo bike build must be approached with chain slack in mind as each model will be different. Here we placed a chain guide on the top portion of the chain and a roller guide/tensioner on the bottom. This was a a perfect fix for chain movement and then to tension the chain without pulling the pulleys of the derailleur to far forward we decided to replace the derailleur. 

Replace the Derailleur


We removed the stock derailleur and replaced it with a Shimano Claris derailleur. Immediately the shifting became smoother and quieter as the chain moved through the top guide and the bottom tensioner. The Claris has a much stronger spring that the stock derailleur and therefor is able to maintain the pulley closer to the cassette as it works through the gears.

Converting a bike to an eBike is not as simple as connecting a motor and a battery to a bicycle. Conversion is the integration of both the bicycle and the motor system in such a way that both will work in harmony.  It is not just adapting the motor to the bike, or the bike to the motor, it is both.   

More changes...


This cargo bike was finished last night. Josh, our lead mechanic, and our CEO have been working on build the perfect cargo bike. In the morning we took it all apart. If we think we can find something that will make this a better bike we will make the changes. We decided to use the very latest Sram GX Clutch derailleur with the new GX shifter. This will change the bike from a 7 speed to a 10 speed with a 11x 34 cassette in the rear. This change will utilize all the benefits of a clutch derailleur and allow for a much better shifting experience. The reason why shifting improves is due to the tight tolerances between the cogs. The 11X34 rear cassette will allow the climbing of hills with a full load and not over work the motor. Today we have to wait for a certain tool to arrive. Tomorrow we will begin the reassembly.

Scott Genius Full Suspension



The above picture is a stock picture but very close to the bike we are converting. Full suspension bikes are always challenging but this one more so due to the built in attachment for a bash guard. If you look real close you will see a red attachment on the bottom bracket. The attachment is removable but the part it is attached to cannot be removed thus obstructing the the axel of the Bafang mid drive motor.

Removing the Flange


There are a variety methods of removing the flange. Josh, our chief mechanic is also a welder. Josh determines the best method and tool to use for this task. Notice that the bottom bracket shell is not the standard 68mm or the 73mm. This is a PF-41 pressfit bottom bracket shell that requires special spacers. Thanks to my friend Matt Hughs of Empowered Cycles in Castro Valley for providing this adaptor.

100mm BBSHD 1000 watt Motor Installed


Installing the motor after the tabs were removed went without a hitch. The large silver spacer is part of the adaptor. 

Battery Placement


This is a picture of the finished bike but is the best view of the battery placement. The most difficult task when building on a full suspension bike is battery placement. This option worked very well because the top of the top tube is flat giving the battery base plate a very solid foundation. Not all bikes would be a good candidate to put the battery in this position but the Scott Genius was a perfect match.

Finished Bike


Yes, same pictures but this is the finished bike. Those of us at the shop were very pleased with the outcome. It is rewarding to take on a difficult build and bring it to its conclusion. We have yet to start a build we could not finish. However, we are not so proud that we are unwilling to call in outside professionals for consultation, or work, at any time we think it necessary.

Test Ride


In a word..."Fun." This bike is light, for its class, agile, comfortable, and powerful. I love the sound of the mountain bike tires as they roar down the road at 28mph. The front suspension of the bike makes for a smooth ride. We are pleased with the build and I am pleased with the test ride.

Yuba Mundo Cargo Bike

Yuba Mundo Arrival


This is a second generation Yuba Mundo Cargo Bike that had been built into a Bionix eBike. When we convert bikes that have an existing eBike hub motor we need to replace the wheel as it too heavy. Hub motor are very heavy and ass unnecessary weight to the bike. That said, the dropouts on this bike are 14mm and the standard is 10mm. Finding a wheel is difficult.

Remove Saddle Bags


When removing saddle bags be careful to remember all the attachment points. Never build a cargo bike without removing the saddle bags as they invariably hide areas that need inspection.

Cleaning the Bike


Typically we do not invert bikes as there is no need but when it comes to long tail cargo bikes this is the only way of cleaning and inspecting the bottom of the bike. So far everything looks in order.....until...Ouch!

For more information on how and why we clean all bikes read our page on "The Conversion Process" on this website.

Safety Details


It is difficult see but on the bottom of the front basket there is a very sharp point left by the welder. These are things we look for to insure no child is harmed by a careless weld, or a sharp Zip Tie, or a poorly attached child's seat. To this sharp edge (which caused a 1/2 inch cut on the palm of my hand) I applied a file and smoothed it out.



I have been asked why I go through such a labor intensive process with each bike? Take their money, slap a motor and battery on their bike and let them worry about the rest. This is why: I have ridden bikes for over 60 years and have suffered many a crash. Once I spent 2 months in the hospital due to a crash in a race. I have lost good friends who perished why cycling. Cycling is dangerous and its danger is multiplied by anyone (a professional bike mechanic or amateur bike mechanic) who is carelessly working a bike without a thought of the safety of the future rider.

This is why we Dissemble


This is the rear disc brake rotor. It is being held by 2 very loose bolts that are half way out of their socket. The rotor rocks back and force It is a miracle that rotor has not torn completely off. I took this whole wheel with the rotor attached and showed several professionals and one of them said, "That s**t is not supposed to happen." He spoke for us all. This is what happens when you install a rotor without LockTite.

This bike carries children and one strong application of the brakes on a downhill would have torn the rotor off.

This is why we tear down every bike we build.

Yuba Mondo Continued

The Rear Derailleur


Most derailleurs can be returned to like new condition if they are removed from the bike, thoroughly cleaned and all the pivot points are oiled. There are two areas of concern with a derailleur. First is the pivot points. Pivot points are very hard to oil while the are on the bike. The derailleur has to be removed to oil ALL of the pivot points. The second area of concern is the pulleys. The pulleys attract all kinds of contaminates. In order to properly clean the pulley wheels they must be removed from the bike and them cleaned and oiled.

Tighten all Bolts


With the bike disassembled now is the time to tighten all bolts, screws, nuts, and any other attachments. It does not take long and it will get rid of most squeaks, rattles, and squeals. With cargo bikes this is very important as many bolts are covered up and inaccessible. Now is the time to tighten all bolts and replace any missing hardware.

Ready for the Motor


Woe...one of the simplest installs in awhile. Sometimes modifications of a bottom bracket shell are necessary for a motor installation but in this case it slipped right in. Yay. A perfect 63mm bottom bracket shell.

Replacing the Rear Wheel


The rear wheel has to be replaced. It is a bolt on 14mm dropout. We will find one!

Update: Thanks to my friends at Alameda Bicycle we were able to find a wheel...now let's move forward to finish the bike.

Finished Bike...Not Quite


At least it is coming all together and will be finished on schedule. We have a policy of one bike, one mechanic, until finished. We try to stick with that policy like glue and the only time we deviate is in case of emergency, technical experience one mechanic may have, Special order parts, or sometimes a client emergency. We had a bike come in that belongs to a Uber food deliverer. He is out of work until he gets his bike repaired! We accomodated him and he is back at work. 

Uh.....Wait a Minute


After a many hours of research to find a replacement wheel for the Yuba Cargo build, time and expense of  purchasing the new wheel, installing rim tape, tube, tire, cassette, rotor and adaptors I stood back looked it over and said..."The Bionx wheel is better."

I took everything apart and reinstalled the Bionx wheel. The Bionx wheel is solid, overbuilt wheel with heavy gauge spokes that was designed for a cargo bike. The Bionx wheel is a true bolt on (no slip from the drops) 14mm wheel that needs no adapters.

The new wheel  I installed used adaptors (14mm to 10mm) that I did not think robust enough, fewer spokes and not at all heavy duty.

Cargo Bikes do not only carry groceries, they carry children and we never lose sight of that fact when building cargo bikes.

Yuba Mondo Continued

Almost Finished


At this point we have installed the wheel skirts and the rail system for the child carrier. The skirts come with white zip ties that I tossed. I have no idea of the quality so I used my own. Also, instead of zip ties I used stainless steel bolts to attach the skirt where possible.

Bike Finished


Well, not quite. But here you can see the bike before we put all the extras on. Today, all will be together and ready for testing! 

Test Ride


The test ride was smooth and powerful. A cargo bike always takes a little getting used to due to its size. Always remember to pick up your feet as it takes off otherwise the running board will contact the back of your foot. Ouch. Anyway, the bike came out beautiful.