Gravel Grinder/Commuter Q128 Carbon

I'm new to the forum and ebike world, but have spent a year obsessing over all of your posts. Such a great community you have here. I'm finally ready to make the jump into an electric DIY bike. A bit about me. I used to race amateur cyclocross, have done a couple of ironman triathlons in my day, but am currently not in great shape. In fact I'm out of shape. I ride maybe 3 times a month at best. I love bikes and have been riding my whole life...feel like an ebike can get me back into this great sport. I want to start out by riding to work again on a regular basis and see where this goes. Here is my goal:

Rider: 230lb, full grown gentleman. Want to ride in normal street clothes, spandex not my friend these days. Worked on bikes a fair amount, not an electrical genius, but know my way around a computer ok.

Ride: 12 mile commute each way, 8 miles of bike path and 4 miles of hectic city riding in the heart of Los Angeles. Mostly flat but with modest 500ft of total climbing one way.

Donor bike: My 2008 LaPierre HM-Lite CX bike (all carbon) 10 speed with mini-V brakes

Bike goals: Want this first ebike to ride, look and feel like a normal bike. Simple, minimal bike.

Speed goals: 25mph+mph on the flats, putting out 100-175 watts of my own power.

Motor: Thinking Q128c (cassette version). 328Rpm, 48v
https://bmsbattery.com/ebike-kit/768-q128c-135mm-500w-rear-driving-ebike-hub-motor-ebike-kit.html

Battery: Thinking Luna Cycle mighty mini, 6AH 30Q cells in a saddle bag.
https://lunacycle.com/batteries/packs/52v/52v-mighty-mini-cube-samsung-ebike-battery-pack-30q-6ah-3-pounds/

Controller: Phaserunner? Something more simple?
http://www.ebikes.ca/c-phaserunner.html

PAS: no clue

Throttle: not necessary, if PAS system works well.


Here are my questions to start:

1) Is the phaserunner controller right for me? Concerned its too complicated. However, I want to get on the bike and feel like its just like riding a bike, with a nice healthy push.

2) I have no clue about which PAS system to get.

3) Lots of pros/cons on the site about the 328rpm version of the Q100/Q128. I think with my relatively flat ride and 48v option, the Q128c/328rpm can get me to the cruising speeds I'm after, but not sure if I'll be happy overall.

4) I want minimal wiring. If I avoid throttle, break cut offs, and readout up on the bars, is this a mistake?

Thanks in advance, will post some pics as this comes together!

You will get much more responses if you can get a moderator to move this thread over to the General E-Bike section.

I ride a 700c wheel Gravel/Sportif Road Bike with the Q100c currently on the rear .

A 10 speed cassette will fit onto a Q100c but there is about 1/3 less turn of the threaded ring that holds the cassette onto a wheel. No big deal since there are 3 or more turns when adding a cassette to the freewheel hub.

A Q100c will not get you to that speed unless you get the 328 rpm version you speak of , but I think it will be the top speed would be about 25mph.
( Mine is a 201 rpm version on 29er disc wheels and my top speed is 20-22 mph in perfect conditions running on a 14s / 52 volt battery pack, with a 15 amp 48 volt generic controller )

However most everyone who uses the faster 328 wind is using 10s/36 volt or
12s battery pack at most, 12s is close to a 48 volt pack, but would probably work just fine on the 36 volt controller that is sold to be used with the Q100c

From what I have read the Q 128 will handle more power in watts and amps so for faster speeds It might be better , but it is heavier and only riding on flat ground you probably don't need the extra amps.
And
I am not sure that the Q128c would take a 10 speed cassette since it is a bigger motor.
Those motors are so cheap you could get one of each and see which one works best.
With such small motors I am not sure if the phaserunner is necessary , It would be nice to have though for a future project.

Bike paths are 15 mph max speed , so keep that in mind for realistic assessment of what your commute time will really be. When pedestrians are on the path I like to keep the speed 14 or under since at that speed or even 12 mph you really startle people when you come up on them.

Donor bike: My 2008 LaPierre HM-Lite CX bike (all carbon) 10 speed with mini-V brakes

Click to expand...

I'm not sure how one mounts a hub motor to carbon pieces, but I'm pretty sure I've read here to avoid carbon bikes. Strength and comfort is what is important to me and I prefer used mountain bikes, but if you must have a road bike, you do not need the lightest or the latest. In fact a cheap(but not Wally World cheap)donor bike makes sense for an Ebike, especially the first build.
The Q128c (cassette version). 328Rpm, 48v motor, in 26 or larger wheel on a 52 Volt battery should top out around 25 mph, plenty fast on a bike w/ no suspension and V-brakes. That motor, if it was rated @ 36 Volts, like all the other versions, would be a 260 rpm @ 36 V mid-speed motor, probably the best motor speed for the majority of riders.
I really don't know anything about Phaserunners, except that they are expensive. There are several recent build threads w/ Q100/Q128, road bikes and Phaserunners, I would suggest you search them out.
You definately want to use PAS, whether it's a simple 3-speed limited you would have w/ a reg. square wave genaric controller or a 5-level "Torque Imitation" that is associated w/ the KT sine Wave controllers or the Phaserunner/C.A. combo. Don't be afraid of a few wires, start w/ a dark donor bike and use blk. wires and people won't notice.

Thanks for the help, this is awesome info to get me started! A few more thoughts below:

ScooterMan101 said:

You will get much more responses if you can get a moderator to move this thread over to the General E-Bike section.

I ride a 700c wheel Gravel/Sportif Road Bike with the Q100c currently on the rear .

A 10 speed cassette will fit onto a Q100c but there is about 1/3 less turn of the threaded ring that holds the cassette onto a wheel. No big deal since there are 3 or more turns when adding a cassette to the freewheel hub.

A Q100c will not get you to that speed unless you get the 328 rpm version you speak of , but I think it will be the top speed would be about 25mph.
( Mine is a 201 rpm version on 29er disc wheels and my top speed is 20-22 mph in perfect conditions running on a 14s / 52 volt battery pack, with a 15 amp 48 volt generic controller )

However most everyone who uses the faster 328 wind is using 10s/36 volt or
12s battery pack at most, 12s is close to a 48 volt pack, but would probably work just fine on the 36 volt controller that is sold to be used with the Q100c

From what I have read the Q 128 will handle more power in watts and amps so for faster speeds It might be better , but it is heavier and only riding on flat ground you probably don't need the extra amps.
And
I am not sure that the Q128c would take a 10 speed cassette since it is a bigger motor.
Those motors are so cheap you could get one of each and see which one works best.
With such small motors I am not sure if the phaserunner is necessary , It would be nice to have though for a future project.

Click to expand...

Really helpful info on the 10 speed cassette and the motor widths. I really want to stay with the existing drive train on the bike. I'll look at the diagrams between the Q100 and Q128 closely and compare the widths. There is an option on Em3eV to purchase a Mac motor with a 10 speed freehub. It's interesting to me, but I'm not sure its a good fit for a carbon bike. Worried about the torque on the dropouts (which are aluminum on my bike). There are a few Q100 builds on here with carbon builds with no issues.

I think I'm going to abandon the phaserunner for this build. read more reviews tonight and think I need to take a dip in the shallow end before swimming in that deep end. Maybe save it for converting my cannondale scalpel mtb with a bbshd in the future. Totally different goals for that bike.

Bike paths are 15 mph max speed , so keep that in mind for realistic assessment of what your commute time will really be. When pedestrians are on the path I like to keep the speed 14 or under since at that speed or even 12 mph you really startle people when you come up on them.

Click to expand...

Definitely agree. In the wee hours that I ride to work, bike path is empty, and in my hey day, I would ride at 22-23mph here in the morning, sometimes getting passed by local racers. To be honest, I see SO MANY electric bike guys on the path now in the last 6 months!! The traffic in LA has gotten so bad that many folks are taking to electric bikes to commute. The ride home in the summer at 5-6pm is a different story. Ride slow, enjoy the scenery, watch out for roller bladers.

motomech said:

Donor bike: My 2008 LaPierre HM-Lite CX bike (all carbon) 10 speed with mini-V brakes

Click to expand...

I'm not sure how one mounts a hub motor to carbon pieces, but I'm pretty sure I've read here to avoid carbon bikes. Strength and comfort is what is important to me and I prefer used mountain bikes, but if you must have a road bike, you do not need the lightest or the latest. In fact a cheap(but not Wally World cheap)donor bike makes sense for an Ebike, especially the first build.
The Q128c (cassette version). 328Rpm, 48v motor, in 26 or larger wheel on a 52 Volt battery should top out around 25 mph, plenty fast on a bike w/ no suspension and V-brakes. That motor, if it was rated @ 36 Volts, like all the other versions, would be a 260 rpm @ 36 V mid-speed motor, probably the best motor speed for the majority of riders.
I really don't know anything about Phaserunners, except that they are expensive. There are several recent build threads w/ Q100/Q128, road bikes and Phaserunners, I would suggest you search them out.
You definately want to use PAS, whether it's a simple 3-speed limited you would have w/ a reg. square wave genaric controller or a 5-level "Torque Imitation" that is associated w/ the KT sine Wave controllers or the Phaserunner/C.A. combo. Don't be afraid of a few wires, start w/ a dark donor bike and use blk. wires and people won't notice.

Click to expand...

Very helpful! I have one aluminum bike in my stable, with is my cannondale mtb. Really want to save this for a bbshd build to ride on the trails. Seems like a few folks have had good luck with low-medium power carbon bike builds here using the Q100 or Q128 motor, so I'm hoping to make this one work...but I share your concern. Not sure if the ones doing these builds are using torque arms or not, I have not seen that mentioned. And this bike is unfortunately all white, to make things tougher for a discrete build! I just love the way it rides and want to avoid buying yet another bike, if I can avoid it.

I looked into the Kt sine wave controller tonight and it looks like it supports 36-48v, which makes it a good option. My goal is get a little more speed and power than a typical 36v build by going with the 48v. I'm a fairly big rider at 6'3 230lb. Let me know if there is a favorite source for buying the Kt with a paired PAS.

Calsurfer,

I did not look at your exact bike, if you have rim brakes then most likely you have 130 mm dropout spacing on the rear of that Carbon Road Bike.
...
Hub motors are at least 135 mm spacing , often more like 136 or a few mm's for smaller-mid size motors, and even wider for the more powerfull hubs.

If you want real light weight then even better than a Q100c would be Kepler's newest friction drive, and now someone named Andre is also using his design . If I did not already have two Q100c 's build up on wheels I would try one of those on a very light road bike.
https://endless-sphere.com/forums/viewtopic.php?f=28&t=84905
However,
even though I like those I am still waiting for someone to make a Crank Drive driving the front chainrings , only without the expensive and reduction units that a high speed ( KV ) R.C. motor usually needs.

You have a Cannondale Scalpel ?

What year is it ?

Well that changes everything, that is one of the bikes that If I found cheap enough I would build up, and sell the Diamondback Hardtail .
Reasons are ...
Suspension is much more comfortable once going over 15 mph and better on your muscles and bones as well.
Being a soft tail it is lighter weight than other full suspension frames.
You can make it even lighterweight by changing out the front fork, or if it has the lefty you are already set with a good front suspension. ( as long as it is still working properly , you know about no more service by Cannondale on the Lefty ? )

The Scalpel will have 135 mm dropouts and disc brakes so will be much more suitable for a conversion to electric.

A much better option for you , and one that I would do ... is to put a 328 rpm Q 100c or 128c or even the H model ( freewheel ) on the Scalpel and run it on a 10s - 12s battery pack.
Then
In the future I would put on the Mid-Drive that is now being developed by and will be in testing sometime soon, the RC motor drive that eCyclist is making.
He is in San Diego , just down the highway from you.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=90432&hilit=Ecyclist

Seems like a few folks have had good luck with low-medium power carbon bike builds here using the Q100 or Q128 motor, so I'm hoping to make this one work...but I share your concern. Not sure if the ones doing these builds are using torque arms or not, I have not seen that mentioned. And this bike is unfortunately all white, to make things tougher for a discrete build! I just love the way it rides and want to avoid buying yet another bike, if I can avoid it.

Click to expand...

If you enlarge (File) the drop outs to fit a hub motor, you will have ruined the bike as far as going back to a regular bike again. Is that what you want?

ScooterMan101 said:

Calsurfer,

I did not look at your exact bike, if you have rim brakes then most likely you have 130 mm dropout spacing on the rear of that Carbon Road Bike.
...
Hub motors are at least 135 mm spacing , often more like 136 or a few mm's for smaller-mid size motors, and even wider for the more powerfull hubs.

If you want real light weight then even better than a Q100c would be Kepler's newest friction drive, and now someone named Andre is also using his design . If I did not already have two Q100c 's build up on wheels I would try one of those on a very light road bike.
https://endless-sphere.com/forums/viewtopic.php?f=28&t=84905
However,
even though I like those I am still waiting for someone to make a Crank Drive driving the front chainrings , only without the expensive and reduction units that a high speed ( KV ) R.C. motor usually needs.

You have a Cannondale Scalpel ?

What year is it ?

Well that changes everything, that is one of the bikes that If I found cheap enough I would build up, and sell the Diamondback Hardtail .
Reasons are ...
Suspension is much more comfortable once going over 15 mph and better on your muscles and bones as well.
Being a soft tail it is lighter weight than other full suspension frames.
You can make it even lighterweight by changing out the front fork, or if it has the lefty you are already set with a good front suspension. ( as long as it is still working properly , you know about no more service by Cannondale on the Lefty ? )

The Scalpel will have 135 mm dropouts and disc brakes so will be much more suitable for a conversion to electric.

A much better option for you , and one that I would do ... is to put a 328 rpm Q 100c or 128c or even the H model ( freewheel ) on the Scalpel and run it on a 10s - 12s battery pack.
Then
In the future I would put on the Mid-Drive that is now being developed by and will be in testing sometime soon, the RC motor drive that eCyclist is making.
He is in San Diego , just down the highway from you.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=90432&hilit=Ecyclist

Click to expand...

That Kepler drive looks awesome! I had looked into friction drives awhile back and got turned off, but this looks much better than anything I have seen. Amazing how they are using it with that vesc controller as well. Going to seriously consider this!

Measured my dropouts and the Lapierre is about 132mm (strange, I know). Not sure why it is slightly wider as compared to my other road bikes. Based on the amount of flex, my instinct is that the 135mm width of the q100 would not be an issue. I also pulled up a diagram of the q128 - has the same width for a 10 speed cassette as the q100 (at least on paper).

My Cannondale Scalpel is a 2008 with a 2009 lefty fork that does need servicing! I had no idea they are not supporting them anymore! I love this bike. Its 24 lbs and its sturdy as a rock. It will be a great conversion bike, but I don't enjoy riding it as much on pavement as I do a road or cx bike. Hoping to make a lightweight commuter bike, and save the scalpel for a mtb conversion. Will be interesting to see how that new mid drive eCyclist is working on. Sounds promising.

Here is the build that originally inspired my q100/128 goals for my cx bike.

https://endless-sphere.com/forums/viewtopic.php?f=6&t=93328&p=1367087#p1367087

His build seems pretty simple, although that friction drive may be the sweet spot!

The Q100c 201 rpm / 700c wheels on my road bike is a good little motor,
It does not get me up the speeds I want ...only 20-22 mph on flat ground , in perfect conditions and with a fully charged battery.
I live in an area with many very serious road bike riders, who have the type A personality and are quite competitive . if you are a Top Tier Major Manufacturer like Specialized it makes sense that they are the people you are going to hire. So I need faster speeds from a motor than 90% of the rest of the population.
For most people the Q100c is a great little motor. And you will be happy with it, even a Q 128c
Don't know if the Q128 c will go faster, but it will handle about 300-400 more watts , I have been told by someone who had both at different times on his carbon cyclocross bike.
Torque arms are a must when using any hub on a carbon frame, I would use thick rubber between the carbon frame and the steel torque arm

I understand you wanting to keep the Scalpel for MTB riding, best to wait for the avian drive for it.

I would order both the q100c and Q128c that way you can try both, each would work with the same controller and display.
and get two controllers and throttles since they are cheap as well but shipping from China is expensive.
Just be sure to order the right spoke hole count on the hub. ( confirm with an e-mail/contact with them)

There is a company ( I forgot the name of it at the moment ) that provides many parts for just about every year and model of Cannondale bikes. A call to Cannondale Customer Service and they will get you the info.
That company makes a headset that will convert any Cannondale that used the Headshox or Lefty
To
A more modern Tapered Front fork.
As I remember the price was good as well , around $ 50
So
You can change out the front fork on your Scapel in the Future , just be sure to get a fork with the same or 10 mm more travel than the current Lefty you have on it now.

Hey Calsurfer, welcome to the community!

I wanted to mention couple things about the Q100 and Phaserunner:

The Q100 is designed to fit in 135mm forks, however, they use spacers and a nut to get that axle width. You can remove the nut and the motor will fit in 130mm dropouts. Or you could replace a spacer with some washers, and tighten the nut against the washers. I was able to get the same Q100 fitted to my single-speed frame which has only 120mm fork spacing. So you can definitely make it fit. There is a Q100c which uses a cassette instead of a freewheel, and the Q100c is also available in a 32 spoke hole setup rather than the 36 hole which most hub motors still use. I don't know if you would be able to fit a 10-speed cassette with a Q100, but you may not need it with the assist you're going to get from the motor. I live in a pretty flat area too, and I'm getting along great with an assisted single speed.

I was using a 328 RPM Q100H on my bike for a bit and it was plenty powerful. I had it on a 13s battery (54.6V peak, 48V nominal) and I was hitting 30 MPH on flat ground. I was putting as much as 20A into the system from the battery, but dialed that back to 18A to mellow things out a bit. The only reason I ditched the Q100 was because I got a lemon from the seller and it would have been too expensive to ship it back, so now I'm trying the even smaller YTW-06.

The Phaserunner doesn't directly support PAS or a torque sensing bottom bracket. If you want to use anything other than a regular throttle, then you also need a Cycleanalyst hooked up to the Phaserunner. If you're using drop bars, I'm developing a nice 3-button throttle for my build and have shared the plans for it in my build thread. I am not a fan of cadence-sensing PAS anyway. The BBSHD uses that, and it seems like I don't have as much control over what the motor is contributing. Most of the time its not a big deal, but other times, it's too much or not enough and I need to mash the PAS levels up or down to adjust it. A throttle allows for much more dynamic levels of assist. That being said, a torque-sensing PAS is pretty nice.

zro-1 said:

Hey Calsurfer, welcome to the community!

I wanted to mention couple things about the Q100 and Phaserunner:

The Q100 is designed to fit in 135mm forks, however, they use spacers and a nut to get that axle width. You can remove the nut and the motor will fit in 130mm dropouts. Or you could replace a spacer with some washers, and tighten the nut against the washers. I was able to get the same Q100 fitted to my single-speed frame which has only 120mm fork spacing. So you can definitely make it fit. There is a Q100c which uses a cassette instead of a freewheel, and the Q100c is also available in a 32 spoke hole setup rather than the 36 hole which most hub motors still use. I don't know if you would be able to fit a 10-speed cassette with a Q100, but you may not need it with the assist you're going to get from the motor. I live in a pretty flat area too, and I'm getting along great with an assisted single speed.

I was using a 328 RPM Q100H on my bike for a bit and it was plenty powerful. I had it on a 13s battery (54.6V peak, 48V nominal) and I was hitting 30 MPH on flat ground. I was putting as much as 20A into the system from the battery, but dialed that back to 18A to mellow things out a bit. The only reason I ditched the Q100 was because I got a lemon from the seller and it would have been too expensive to ship it back, so now I'm trying the even smaller YTW-06.

The Phaserunner doesn't directly support PAS or a torque sensing bottom bracket. If you want to use anything other than a regular throttle, then you also need a Cycleanalyst hooked up to the Phaserunner. If you're using drop bars, I'm developing a nice 3-button throttle for my build and have shared the plans for it in my build thread. I am not a fan of cadence-sensing PAS anyway. The BBSHD uses that, and it seems like I don't have as much control over what the motor is contributing. Most of the time its not a big deal, but other times, it's too much or not enough and I need to mash the PAS levels up or down to adjust it. A throttle allows for much more dynamic levels of assist. That being said, a torque-sensing PAS is pretty nice.

Click to expand...

Thanks zro! I have read through your build of the single speed a few times for some inspiration. I'm really impressed with the diagrams and planning you put into your builds. I'm an architect by trade, so the planning and designing aspect is really interesting to me. Now if I could just hire a contractor for the execution, I would be all set, ha. I have some serious envy of that saddlebag battery, but I saw you found it too top heavy. I was honestly planning something similar, but with a luna mighty mini, but I'm torn after hearing your comments. I want stealth, but am also very sensitive to the way a bike feels. Really interested to see how the YTW-06 works for you on the bike. Intrigued by the size, and it looks great. The 3 button throttle sounds perfect for these types of builds.

I may end up pulling the trigger on the q128c just to get this build off the ground, and use a standard thumb throttle to start. Leaning towards an infineon controller for now, because I'm still worried about tackling the phaserunner on my first build

ScooterMan101 said:

There is a company ( I forgot the name of it at the moment ) that provides many parts for just about every year and model of Cannondale bikes. A call to Cannondale Customer Service and they will get you the info.
That company makes a headset that will convert any Cannondale that used the Headshox or Lefty
To
A more modern Tapered Front fork.
As I remember the price was good as well , around $ 50
So
You can change out the front fork on your Scapel in the Future , just be sure to get a fork with the same or 10 mm more travel than the current Lefty you have on it now.

Click to expand...

Very good to know, my lefty just loses air so quickly - works fine around town but its thrown me over the bars once on the trails because it bottoms out. Will definitely give them a call about the parts!

calsurfer said:

Thanks zro! I have read through your build of the single speed a few times for some inspiration. I'm really impressed with the diagrams and planning you put into your builds. I'm an architect by trade, so the planning and designing aspect is really interesting to me. Now if I could just hire a contractor for the execution, I would be all set, ha. I have some serious envy of that saddlebag battery, but I saw you found it too top heavy. I was honestly planning something similar, but with a luna mighty mini, but I'm torn after hearing your comments. I want stealth, but am also very sensitive to the way a bike feels. Really interested to see how the YTW-06 works for you on the bike. Intrigued by the size, and it looks great. The 3 button throttle sounds perfect for these types of builds.

Click to expand...

I'm actually going to be building a new seat-bag battery as a side project. I think that a lot of my first impressions were due to the major change in rides. I was coming from a crazy-heavy old-school FS MTB with a BBSHD and battery on the down tube, to a super-light no suspension track style single speed frame. The ride was so different from what I was used to I think I jumped to conclusions about the battery being in a seat-bag. As I'd gotten some miles under the new frame, I realized that a lot of what I thought was the battery weight was just the change in weight ratio between myself and the bike. I mis-interpreted the nimbleness of the bike to the batteries tossing the bike around. By no means should you discard the idea of a seat-bag battery based on that one comment I made. I was probably very wrong.

I hear you in regards to the execution side of the design/build process. I'm going on to the 3rd attempt at actually making my 3-button throttle because I keep making dumb mistakes with soldering things together. I have a working prototype now, but it's so ugly and sloppily put together I don't want to keep it on my bike. I'm basically just using it to test the throttle input to the Phaserunner controller.

Also, if you get the mighty-mini, you can start by putting it in a seat-bag and if you don't like how it feels, you can move it somewhere else. That battery would work as a backpack battery or in a little frame on the down tube.

@calsurfer - I was in the same decision making stage 3 weeks ago and ended up purchasing a front hub ebike kit from Dillenger. Mostly because of it being a complete integrated unit. I was pricing out stuff from BMS but the shipping costs kills it for me. In my opinion, mixing and matching allows you to get what you want but can be frustrating and time consuming.

The one thing that was a problem for me was the PAS ring, my 2018 Fastroad Comax 1 has not enough space to mount it. So I had to customize my own solution, this is a common problem with carbon bikes so make sure to take that into consideration.

I can get to 25mph no problem and hills are way easier, even steep grades. Thats a 350W motor only and battery is 13AH @36V.

Good luck.

zro-1 said:

Also, if you get the mighty-mini, you can start by putting it in a seat-bag and if you don't like how it feels, you can move it somewhere else. That battery would work as a backpack battery or in a little frame on the down tube.

Click to expand...

Thats a good plan. Also realized that the mighty mini at 52v may require a more robust controller than a typical 36-48v controller. For some reason, i was thinking that was not an issue, but I think I'm better off with a controller that can handle 72v and dialing it back. Looking at the 9mosfet infineon from em3v.

You definitely shouldn't use a 52V battery with a 48V controller. There are a number of reasons, but the main one is that the low voltage cutoff will be too high and you won't use a significant portion of your battery's capacity.

royco said:

@calsurfer - I was in the same decision making stage 3 weeks ago and ended up purchasing a front hub ebike kit from Dillenger. Mostly because of it being a complete integrated unit. I was pricing out stuff from BMS but the shipping costs kills it for me. In my opinion, mixing and matching allows you to get what you want but can be frustrating and time consuming.

The one thing that was a problem for me was the PAS ring, my 2018 Fastroad Comax 1 has not enough space to mount it. So I had to customize my own solution, this is a common problem with carbon bikes so make sure to take that into consideration.

I can get to 25mph no problem and hills are way easier, even steep grades. Thats a 350W motor only and battery is 13AH @36V.

Good luck.

Click to expand...

Thanks Royco, I understand how you went that route. That 2018 Fastroad Comax is a sweet bike! The front hub is an ok ride?

The thing that bothered me about the kits on grim an em3v were that they seemed to be using the same parts from BMS, but packaged together at a premium. Main difference I see is the controllers on BMS are pretty generic...but I'm new to this so I'm just speculating.

Completely separate but positive note - I just talked my dad into an ebike, and we ordered him a haibike urban plus with a 500w transx mid drive, 10ah battery. Such deals on these right now! It's being shipped this week. Will be interesting to see how my hub build compares to this pre-built mid drive bike. The haibike certainly has more features, but I suspect I'm going to like the hub drive better on the road. I recently test road a boshe farraday bike and a stromer side by side, definitely preferred the stromer 500w hub motor over the more expensive boshe bike.

zro-1 said:

You definitely shouldn't use a 52V battery with a 48V controller. There are a number of reasons, but the main one is that the low voltage cutoff will be too high and you won't use a significant portion of your battery's capacity.

Click to expand...

glad you confirmed...I was definitely heading down that path before thinking the volts were "close enough" but now see thats not the case.

I actually had it backwards, but the same principal applies. The controller set for 48V would have a LVC around 40-ish volts (13s times whatever the controller was set to be a safe voltage cutoff), but that might be too low for a 14s battery which would have a higher safe minimum discharge.

Sorry for the confusion. Either way though, you want to match your battery voltage and your controller.

There are many people here that use a 14s battery pack ( 52 volt ) with 48 volt controllers. Myself included.
and I do not even have a BMS on my Lipo Battery Packs.

First of all if you are going to buy a 18650 cell battery pack from any of the trusted vendors it is going to have a BMS included. And one of the Functions of the BMS is to not let the pack get below a certain voltage.

Then If you are worried about being one of the very few who get a defective BMS, which is a very low probability it the first place as long as you buy from a trusted quality vendor,
then just do what I do .
I have the lowest voltage that I want to go to , written and taped onto my display.
If you ride an electric bike like you should, keeping an eye on Speed and Battery usage during your ride. there will be no problems. ( You do that already with any other motor vehicle that you drive Car/Motorcycle/Etc. ).

When I get down to near the voltage written down there in plain sight I slow down, and/or switch battery packs.
On my bikes the controllers are 48 volt , and I use both 12s packs and 14 s packs on them, often switching between packs during each ride. ( Using the 12s when going up to the higher areas, then once up there switching to the 14s pack. and switching back to the 12s pack if I start to run low on the 14s pack.
With smaller packs ( 11 amp hour packs or less ) This is very easy to do. and has the added benefit of extending battery life and not letting any pack get two low.

TIL that BMSes will monitor both charge and discharge levels. Up until now I had though that the BMS mostly managed charging and max amps discharge, and the controller managed minimum voltage, but that is wrong. From Vruzend.com:

A Battery Management System, or BMS for short, is used to protect your battery during charging and discharging.

During charging, the BMS will monitor the voltage of all of your cells and balance the cell groups to ensure they are charged equally.

During discharging, the BMS will monitor the voltage of all of the cells, as well as the entire pack voltage and the discharge current. If the BMS determines that any of its preset limits have been passed, such as the battery draining too low or an unsafe amount of current being pulled from the battery, the BMS will cut power to the battery to protect it from damage.

Click to expand...

So, with that in mind now, I guess it would be OK to run a 52V nominal pack with a 48V nominal controller. I humbly apologize for the misinformation.