Custom E-bike BMC V3 1000W on GT Transeo Cross-tour bike

mvly

10 kW
Joined
May 25, 2011
Messages
916
This will be a long review, so bear with me.

here are the criteria for my ebike build:
1) Hydraulic disc brakes - I wanted to can stop well enough during an emergency. Moreover, the feel of a hydraulic disc brakes is much better than mechanical disc or V-brakes.
2) Hybrid Bike - I wanted a Hybrid bike so I can take it on road and off road and be fast on both worlds. Many people here used a mountain bike for the conversion, but I didn't want to added a lot of unnecessary weights to my bike if I will not be doing hardcore off-roading. Moreover, I doubt the bearings in electric hub motors were designed to handle hardcore off-roading.
3) Needed at least Front Shocks - I have used my road bike with carbon forks and I feel every bump and pot hole. With a front shock I can mitigate the impact and increase rideablity. Moreover, hitting a pot hole at 30+mph without shocks would probably destroy stuff. : )
I figure this only helps for my comfort and maybe a bit easier on the bike frame. But this again this might increase parts that need to be maintained.
4) relatively cheap bike - I am NOT going to buy a titanium frame cross-tour hybrid bike with front shock for $2K and then convert it. The electronic parts and battery will already cost a shit load.
5) Motor that can freewheel - I wanted to use the bike as a regular bike if I needed to. Plus, freewheeling can really extend range if I coast a lot.
6) Fast ebike conversion - I wanted to go at least 35+mph top speed because I know of roads that will require me to go that fast just to be safe, even though I might be breaking the law a bit.
8) At least 30 miles range full electric with no assist.
9) Budgeted Less than $3000 over all system.

That being said, Here is the bike/motor/controller option

Bike: GT Transeo 2.0 2010 black Small Frame
Motor: BMC V3 1000W
Controller: BMC 50A modified to work with Cycle Analyst
Battery: ebay battery (daojio666) 36V20Ah for now. 48V30Ah (asian-resources_com) ordered and on its way here. I will add on to this post once I get that battery and test it.

Here is the bike's Specs:
http://www.gtbicycles.com/bikes/archive-1/2010/transeo-2-0-disc
Frame: Site say 7000 series aluminium, but I suspect it's 6061 Aluminium since it's heavier than my 7005 Aluminum road bike.
Price: ~$440 after rebates, coupons, tax, etc.

Here is my quick review of the bike itself:View attachment 11 (before Conversion)
Pros:
1) Not too heavy - perfect for ebike build.
2) Hydraulic disc brakes - definitely needed for a ebike that is fast.
3) Tires are pretty good - definitely needed for light off-road and super on-road rideablity. A bonus is the side reflector painted on the wheel. It really shows when pointing a light source at it. I do have side reflectors anyways for added precaution, but the tires itself does a swell job of illuminating at night.
4) Front Air shock with remote lockout - the remote lockout is a nice feature, but I don't see myself using it that much. The front shock however is heavily used! : )
5) Price - I couldn't find any other bike out there with this specs that was in this price range for around $440.

Cons:
1) No rear shock - I can live with this one.
2) Shifter and crankset are of lower end bike - I can't really complain on this one since I did pay only $440 Out the Door for this.

Over all, the bike feels good. It's not super heavy or light. It handles pretty well. The shifters are dead on... for now. 8 speed was a bit too much since, most of the bike build were 7 speed and below, but I figured it should be fine. I originally debated if I should have gotten a medium or a small. But understanding that I might not be the only one that will be using it, I decided on a small instead. A medium size would have given me more triangle room (the triangle in the center of the bike) for battery.

Motor:
BMC V3 1000W hub motor $438 - (from ebay hi-powercycles) when they had "fire sale" on there BMC V3 motors.

Pros:
1) Freewheel with not power - There is still a super low resistance, but only a super low speed. The weight of the bike makes this resistance none existence because of momentum of the bike once it is moving. I can coast for quite a long time just like a regular bike. If I turn off the motor, it feels just like a heavy bike.
2) 1000W - This is plenty of power for starting and accelerating fast.
3) Planetary geared - This really helps with the efficiency because I can coast without much loss of speed.
4) Ultra fast! - I have hit 33mph on electric only on flats with I let it go to 30Amp current limit on only 36V LiFePo4 battery! I will explain more below on the controller section.
5) Supposedly weather sealed so riding in the rain shouldn't be a problem, though I have yet to test this.

Cons:
1) Some vibration noise at 24mph-26mph. I don't know if it's the motor or the spokes, but I would say it's the motor since when I let go of the throttle at 25mph, the noise goes away. Moreover, all the spokes seems to be solid.

Controller $215 + Cycle Anaylst $120:
BMC 50A Controller modified by ebikessf.com to work with Cycle Analyst.

Pros:
1) Modified so it works with Cycle Analyst - I highly recommend this. I have read reviews on this fourm where this motor's wire burnt out or the motor itself burnt out because people were putting too much power into their motors during hill climbing. With this modded Controller, I am able to precisely control how much power goes to the motor.
2) Accepts 36V or 48V - I like this feature because I can switch between the batteries voltages. You just have to make sure you set the jumpers for each setting.
3) Full Current/speed control with the Cycle Analyst - this is pretty important to keep your motor and wiring safe.
4) Cycle Analyst easy to use control - It's pretty easy to use the Cycle Analyst. ebike.ca made this just right!

Cons:
1) Jerky Start - When I start bike up on motor only, it is a bit jerky. Maybe it's the way to turn the throttle, but still it's a bit difficult to get a smooth start. It might be caused by the soft start, but I will try this without it later on. I have a 800W electric scooter that starts up very smoothly as compared to this.
2) Control Delay - I can atest to this one. Someone else on the forum has pointed out that this controller has a delay in control when speeding up while moving. I don't know if it's because of the mod or something else, but there is a delay on when I turn the throttle to when it actually puts more power in when I am coasting and want to speed up. I did not notice this when starting from a stand still though or if I had the throttle half way. It might be something there to protect the gears or motor... maybe.

Battery:
1st Battery: 36V20Ah - $389
2nd Battery: 48V30Ah - pending will add review on this later $789

36V20Ah:
Pros:
1) LiFePo4 - so it's pretty light and has high capacity.

Cons:
1) It rated for 20Ah, but actually less - According the Cycle Analyst I only got 17.5Ah. According to the daoji666 I need to cycle the battery a couple of time before I realize my max capacity. However after a couple of runs and cycling, the battery, the capacity still is 17.5Ah. I will do some more testing afterwords if time permits, but so far after 3 range test, and many recharges, the capacity is still 17.5Ah. Maybe he skimped on a few parallel cells. For the price, it's still good capacity for the money, but I don't like people lying to me. If he advertised it as 17.5Ah, I would totally be fine with that. So this is a word of caution for people buying from daoji666. Just make sure you contact him and tell him that you read somewhere that someone bought his battery and the capacity is lower than advertised after a few cycle of the battery.
2) only rated for 20A Continuous, 40A Burst using the provided BMS. Most other battery usually is rated for 2C meaning 40Amps Continuous. But I think this battery cheaped out on the BMS.

I used this battery initially for my 800W electric Scooter, but later on decide to use it for my ebike. I might return it for the scooter, but for now it will serve the bike. : ) Initially I set the Cycle Analyst to limit the current to 33Amps and the BMS of the battery shut down after it got too hot. it might be my fault too because I put the BMS in the topeak bag instead of outside to cool it down. When it shut down, it was really hot, but thankfull it worked after it cooled down. Looking that specs on the ebay site, I realized that the BMS is only rated for 20Ah continuous. I, since then, set my Cycle Analyst current limit set to 25A and it has not given me trouble since. It does get warm after long rides. After testing the range for a while on 25A current limit and finding that the BMS was fine, I increase it to 30A. It will give me faster acceleration and higher top speed.

Additional Parts. I used amazon link to all of them for reviews and specs look up. Note the price listed is what I got it for not what amazon shows.

1) Topeak DXP MTX w/ side pannier $65 - Definitely something needed like this so you can put stuff in it like your battery.
http://www.amazon.com/Topeak-Trunk-Bicycle-Molded-Panels/dp/B000ZKES0S/ref=sr_1_1?ie=UTF8&qid=1307945964&sr=8-1
2) Topeak Super Tourist Disc $37 - Turns out I didn't need the Disc version since my disc brakes were recessed. Overall the rack is nice, though it was tad more expensive compared to the non-disc version.
http://www.amazon.com/Topeak-Super-Tourist-Tubular-Bicycle/dp/B000ZKHN6Y/ref=sr_1_1?ie=UTF8&qid=1307945982&sr=8-1
3) Fenix TK30 MC-E 630 Lumens Flashlight $105 - This is a must. I have used powerful bike light before, but it were only meant for other people to see you. But with this one, I can see the road and them! I look like a motorcycle from far away.
http://www.amazon.com/Fenix-TK30-630-Lumen-Flashlight/dp/B002UMAIH6/ref=sr_1_1?ie=UTF8&qid=1307945999&sr=8-1
4) Fenix Flashlight mount $14 - This is also a must for just mounting that powerful flashlight of mine.
http://www.amazon.com/Fenix-Mount-lights-18-22mm-Diameter/dp/B0040JRHG2/ref=sr_1_1?ie=UTF8&s=hi&qid=1307946012&sr=8-1
5) Mirrycle Mountain bike Rear View Mirror $13 - This is also a must since it really helps you see what's behind you.
http://www.amazon.com/Mirrycle-MTB-Mountain-Bicycle-Mirror/dp/B0009R96YK/ref=sr_1_1?ie=UTF8&qid=1307946139&sr=8-1
6) Sunlite Double Kickstand $26 - This is also a must since it lets you stand the bike up. It is really sturdy and highly recommend this. Dual Kick Stand.jpg
http://www.amazon.com/Pyramid-Sunlite-Double-Kickstand/dp/B000AO9Z7K/ref=sr_1_1?ie=UTF8&s=sporting-goods&qid=1307946191&sr=8-1
7) 2 18650 UltraFire 3600mah battery + Ultrafire quick charger for my TK30 $25 - this one is from ebay. I usually charge after 2 night use on my TK30 (~ 45 minutes each) just so that I don't run out of battery during a night ride.
http://cgi.ebay.com/UltraFire-3600-mAh-18650-Recharge-Charger-WF-139-bat-/250811070419?pt=US_Batteries&hash=item3a658137d3#ht_3636wt_905
8) Battery mount build ~$12 - took me about 2 days to build with the help of my brother. All in all, I think it's a must to even distribute the weight for the bike.
9) Planet bike Super Blinky - Definitely a must for night riding. Super Blinky.jpg
http://www.amazon.com/Planet-Bike-Blinky-eXtreme-Bicycle/dp/B000KBEH1W/ref=sr_1_1?ie=UTF8&qid=1308434626&sr=8-1
10) Topeak Weather bag - A must if you plan to ride in rain
http://www.amazon.com/gp/product/B000FI6YN4
11) Planet Bike Bracket - A must for the mounting the super blinky on the topeak rack.
http://www.amazon.com/gp/product/B000IQEAK2

Now to the good stuff: Ebike review

Process:
1) I did a lot of research on what I need for an ebike and the different kind (hub visit crank drive, etc).

2) I knew what I wanted so I bought all the parts from the various place to get the best price.

3) I contacted ebikessf since his website was really detailed on BMC motor stuff. He also posted on this website on the BMC controller/motor problems. So I figured that he was the best person to contact and ask question and build part of the bike for me.

4) I got the battery first form daoji666 for my ebike. I also placed the ordered for the 48V30Ah for asian-resources_com since I knew that I can only get 35+mph using a 48V battery. I also needed 30Ah to make sure that I can get 25miles with hills with battery to spare.

5) To my luck, hi-powercycles from ebay had a sale on BMC V3 motors. I guess they are having closeout sale or something. I could not find anywhere online where the BMC V3 motor was $438.

6) I then went to buy the bike itself. Performancebike.com had the bike for super cheap. Combining this with the coupons they were running and the promo for 2x points back on GT bike purchase during April, I had NO reasons NOT to buy it.

7) I then proceeded to contact Illa From ebikessf and he was very helpful, though a bit slow on the email response. He recommended the Modified BMC 50A controller so that I can control the power going to the motor to not burn it out or kill the composite gears during acceleration or hill climbing.

8) ebikessf quoted me on the labor and controller build with all the extra parts like bolts for my disc brakes, the Cycle Analyst, the BMC 50A modified controller, etc.

9) Since I wanted to use my current wheel to have a matching set, I sent in my current wheel and the motor I got to Illa to mod. It turns out that the wheel was short of spoke holes. So I ended up paying more for a wheel that Illa provided. Shipping and a box cost killed me on this, but I figured it was well worth it since I did get the motor for low price.

10) About 2 weeks after sending the motor and wheel, I got that shipment back. Illa is fast on the wheel build and return. By now, I have since prep the bike for the install, i.e. install fenders, light mount, rear rack, the topeak bag to house the battery, kick stand, etc.

11) After getting the bike, I proceeded to install the wheel, only to find that the torque arm did not fit properly on the bike. Moreover, I really didn't need it since the motor only slides in. The twist throttle also inhibited the gear shifting. And the disc brakes slightly rubbed on the outside casing of the BMC V3 motor.

12) I proceeded to fix the problem one by one.
a) I fixed the twist throttle and the shifting problem by cutting away from the throttle to make space for the shifter.Throttle hack.jpg
b) I fixed the torque arm not fitting by using a grinder and filer to cut a section away from the troque arm. As of now, it's not connected to anything. Eventually I will connect it to something.Disc Brakes Torque Arm Mod.jpg
c) I fixed the rubbing problem on between the motor and the disc brakes via thin washers. It provided just enough space to prevent the disc brakes housing and the motor casing to rub. See pictures.Washers to fix Clearance Problem.jpgDisc Brakes Motor Clearance.jpg

13) After the full build, I did some quick soldering to get the dean connector on the battery and connected it up to the controller. After a few connection, the dean connector became pretty chard up (blacken by the high voltage spark caused by the capacitor not being pre-charged)

14) I didn't want to make the hack that Illa suggested on the youtube video to seperate the controller and the capacitor power. So I found out on this forum that people are using resistors to precharge the capacitor before connecting the main power line. So I built the pre-charge circuit and tested it. It was pretty crude, but I used 2 100Ohms (10W or something like that) resistors from radio shack with a 10A switch. It still sparks, but much less and does not damage the dean connector as much. Bike Cable Extension and Precharge Mod.jpg

15) After a couple of initial tests, I found out that the bike was difficult to lean during turns due to the heavy weight on the rear (motor + rack + bag + battery). So I decide to build a housing for the battery in the center of the bike. That took like 1 day of planning and work with the help of my brother. Leaning the bike during cornering is so much easier now. If anyone building a bike, I would highly recommend finding ways to put the battery low and center of the bike. It makes a world of difference.Battery Housing Mod.jpg

All in all I think this is a pretty good setup.


Using the 36V20Ah battery, (really only 17.5Ah according to the Cycle Analyst) here are some good points:
a) range: 18.9miles full throttle no pedal assist.
b) top speed on 30A current limit: Flat w/o wind: 30mph average, 33mph best | Flat against wind: 27-28mph
- I could increase the current limit, but that might prematurely shutdown the BMS. Remember, this BMS was rated only for 20A continuous and 40A burst. I am already using it at 30A continuous, so I didn't want to push it any harder.
c) Power usage at 30A current limit: around 1070W average, decreasing a bit to 1000W when battery is low. I hear that this motor can safely handle 1400W continuous, but I am not ready to test this fact yet. Accelerating from stop sometime spikes the power usage to 1300W for a second or so. I don't anticipate this to be a problem since it's only burst.
d) cost to recharge the battery: ~ $0.17 which is 1KWh and rates are from SDG&E here in San Diego. Battery is 36*20 = 720Wh, but factoring in inefficiency, I say 1KWh is a good estimate.
e) So far, I do not have encounter any police that has given me trouble. I just keep under the radar by going 25mph whensee one.
f) I have not done rain test since I still need to figure out a way to waterproof the battery and circuitry.
g) What I really like about this motor and bike setup is there is no need to pedal. If I pedal assist, I can accelerate to 30mph as fast, if not faster, than a normal car accelerating. I usually catch motorist off guard since they think I will take a long time to speed up, but I end up leaving in the dust... at least for a while. : )
h) Since this is a new motor and bike setup, I did not do much maintance on it other than checking cables and spokes. So far so good.
i) Battery is good for at least 1000 charge cycle according to daoji666. We will see how many I can get...
j) After a full throttle test until battery is dead, the motor is the hottest part of the bike. It is actually hot, not warm as some other people have stated using the BMC V3 motors. I guess they are not continuously using full throttle for constant 35-40 minutes. The controller is only slightly warm. The battery is warm, the BMS is warm/hot, as expected. The disc brakes are not since I did not use them much, but I have seen time when it was warm when I got home. : )
k) I average around 1.1mile/1Ah if I am using full throttle on 30A current limit using the 36V20Ah battery.
l) overall cost is around $3000 if you include both the 48V30Ah and the 36V20Ah battery.


That is about covers the review. See the pictures for more details. Here is the final build picture. Full Bike Converted.jpgFull Bike Front View.jpgView attachment 4

All in all, I am proud of this ebike build. Forgive me for any grammatical mistakes. It is a long review and I did not do a thorough read and edit.
 
Here is some updates:

I since current limited both battery to 35A just so that I can get some speed. The 36V20Ah battery has a pretty crappy BMS and if I run it at 35A for too long, it would cut out due to overheating. I will have to look into how to cool it down.

Here is the specs:
CA set to 35A current limit. note that the speed is pretty accurate since I calibrated it with a GPS.

Batteries-------------------
36V20Ah (really only 17.5Ah according to CA)
Top Speed ever - 45mph during downhill
Average Top Speed on flats w/o wind - 28-29mph
Average Top Speed on flats w/ wind - 26.5-27mph
Average Power Usage at 35A current limit indicated on CA - 1280W
Max Distance at full throttle w/o cut out due to heat - 18.6miles

48V30Ah
Top Speed ever - 50.5mph during downhill
Average Top Speed on flats w/o wind - 34-36.5mph
Average Top Speed on flats w/ wind - 29-30mph
Average Power Usage at 35A current limit indicated on CA - 1750W
Max Distance at full throttle - 32.7miles

Motor-----------------------
I notice a high pitch whiny noise on my motor after about 150miles. I fixed it using some lubricant on the motor bearings.
The gear grease is also spilling out in a radically direction. This might be due to me going 50mph, too fast for casing to contain the grease inside the motor. I might have to grease it later once I hit around 2K miles

Total Range on the motor: 250 miles so far.

I have also done a distance test and the bike has not run into any problems... beside the problem of BMS overheating and shutting down. I usually just reset and everything is good again.

Controller-------------------
Overall i am impressed. After riding hard for 2.5 hours (averaging 20mph, this include stop and go) and using 2 batteries, the controller only got warm to hot, but not too hot to touch for extended period of time.

Overall Setup after long range test:
1) motors is pretty hot, but no hotter than if I just went 5 miles full throttle
2) controller is warm to hot, but normally warm if I use 36V battery or if I keep the distance traveled to a minimal
3) brakes is super excellent. I had to slow to a stop from 45mph and the hydralic disc did the job. The brakes did smell a bit burning after that stunt
4) bike - Overall no problems yet. I just have to check a few things here and there before a long ride. The tires does lose pressure faster than my other bike, but maybe that is due to me using it more often now compared to the others.
5) Topeak Super Tourist Disc rear rack is having bending problems due to the heavy battery and the rough terrain my bike has gone over. I will switch it out for a regular Topeak Explorer.
 
Ok after around 420 miles, the motor died due to phase and the sensor wires fusing due to the heat. I am currently in the process to fix the motor. I was running 35A at 48V up a hill with minimal pedaling when this happened. I was able to obtain another BMC V3 motor and now only run it at 30A.

So new data for 48V30Ah battery w/ BMS set to 30A:

Average Power usage at max speed: 1520W
Average Max speed on flat w/o head wind: 34-35mph
Average Max speed on flat w head wind: 29-30mph
Max speed downhill: 48.6mph
Round trip to work everyday: 46miles
Average power usage per mile: 40Wh/mile
average power usage 1 way: 920Wh
average speed during trip: 23-24mph.
average trip duration 1 way: 54 minutes

I charge at work and at home.

Average Max speed on flat w/o head wind w/ pedal assist: 37-38mph

Currently I pedal only if power is >= 1500W and speed is less than 26mph.

And on hills that I can pedal hard or just too lazy to pedal hard, I keep the power input to around 1000W.

Regardless if I am lazy or not, I always pedal uphill.

So far it has been holding up.
I lubricate the bearings every day to keep it rolling in best condition.

I also made some mod to the rack to accommodate the 31lbs battery plus other stuff like charger and spare tubes.

I will get more pictures later on.
 
I missed this thread last month when you started it. NIce build!... very similar to my 5th and 6th ebike builds. Only I switched to full suspension mountain bikes because I kept breaking spokes on my rear wheel when using only a hard tail hybrid frame. I'm now able to put fatter 2.5-inch balloon tires. Together with the rear suspension it's a much more comfortable ride. Not only do I not break anymore spokes but I can now roll over potholes and railroad tracks much easier. I should also mention I'm a big heavy guy at 270 lbs.

I see you've burned up your motor after 1 month of hard riding. Don't worry it's happened to me and others too. After the first few hundred miles I've burned up phase wires, hall sensors, and even grinded up one side of bearings and part of my axle riding my motors too hard. Illia at ebikes-sf.com helped me take apart and fix 2 of my motors.

I've since learned to back off considerably. Yes the motors are capable of 36+mph but I now keep my speeds down around 25mph and 900W or lower most of the time on my commutes and I've upgraded to thicker 10 gauge phase wires and I haven't had any problems since. In fact last week I've just passed 6,300 miles on one of my V3 motors. I also pedal hard when climbing steep hills and try to keep it below 1200W.

Oh and I noticed my motors whining louder too after a while and I've found that adding a little grease to the planetary gears and the outer ring gear helps quiet it down again. You just need to unscrew and remove the side plate to see the gears. I used that special red synthetic aircraft grease (Mobilgrease 28) that BMC originally uses in their motors.
 
mvly said:
Ok after around 420 miles, the motor died due to phase and the sensor wires fusing due to the heat. I am currently in the process to fix the motor. I was running 35A at 48V up a hill with minimal pedaling when this happened.

(35A) x (48V) = 1680Watts!
How many minute (or seconds) were you continuously pumping that kind of power thru the motor before it died?

I did the same thing with one of my motors when climbing a mountainl at 1800 watts continuous. These V3 motors can really only handle 1250 watts continuous. Anything above that then bad things start to happen. I only have one of my ebikes that has modified controller and CA to limit current to 30A (which is about 1300 watts). The other ebike is unlimited. But I've just developed a habbit now to watch the CA closely and make sure input power to the motor is 1200W or less when climbing or going 30+mph for more than a minute.
 
Sacman said:
mvly said:
Ok after around 420 miles, the motor died due to phase and the sensor wires fusing due to the heat. I am currently in the process to fix the motor. I was running 35A at 48V up a hill with minimal pedaling when this happened.

(35A) x (48V) = 1680Watts!
How many minute (or seconds) were you continuously pumping that kind of power thru the motor before it died?

I did the same thing with one of my motors when climbing a mountainl at 1800 watts continuous. These V3 motors can really only handle 1250 watts continuous. Anything above that then bad things start to happen. I only have one of my ebikes that has modified controller and CA to limit current to 30A (which is about 1300 watts). The other ebike is unlimited. But I've just developed a habbit now to watch the CA closely and make sure input power to the motor is 1200W or less when climbing or going 30+mph for more than a minute.

Hey thanks for the reply.

To answer your question, i was going up a steep hill with minimal pedaling pushing 1.7KW into the motor. Normally the axle does not heat up. It's really the motor itself that gets hot. In any case, it was the continuous 35A or more going through the phase wire that melted the insulation and fused the sensor GND line with one of the phase wire. To put into perspective, i was running it at 1.7KW constant for while before hitting the hill. So it was hot to begin with.

You should look at the new BMC V3 Version 2 motor from hipowercycles. They are going for 599+24 bucks shipping. It's a bit steep, but supposedly it has dual 14Gauge (9 gauge equiv) wires running out of the axle with other good stuff that might make it better at handling high power. I might just get one to try out myself if only I had the cash. : )
Here is the link:
http://endless-sphere.com/forums/viewtopic.php?f=31&t=31083

I now keep the current to 30amps. So far so good. The motor gets really hot after the 23 miles ride, but no problems so far. I will open it up this weekend to see how it is holding up. All the specs I stated is true, I. E. I have been running it constant at 1.5kw for pretty much the whole trip. I think the key is to keep the motor moving. Keep all the power going in to kinetic energy as opposed to heat. That is why I always pedal going up hill. And when i do pedal uphill, i always keep it at 1KW just to be safe. If the wires turns out to be fine when i open it up, I might increase it to 35A again just to get the extra speed during the flats. : )
 
Ok some more update.

I opened the motor and everything looks fine. No melted insulation or damage gears. I took this opportunity to add more grease to my gears. Now it runs a bit better since it's not all dry in there. I also lubricate the bearings a bit. I briefly tested the motor at 33A and easily got 40mph, however, I lowered it back down to 30A since that has been working for me. I can risk killing the motor again for a bit extra speed, but I doubt I will be doing that... at least not until I get the broken BMC V3 working again.

I cleaned up the motor outside casing and wheel a bit.

Here is the updated bike:

I wanted a clean stealthy look so I removed the center battery holder. So far the rack battery is not that bad. The bike is a bit wobbly during pedaling, but I mostly use the electric part anyways.
View attachment 8

I now mount the controller on the side. Once the pannier is down on that side too, it looks like just another bike.
View attachment 7

All the battery cable and BMS is located inside the Topeak Bag. I had to get the largest one they offer to get it to fit.
View attachment 6

First Maiden voyage on this new BMC motor, I got a flat, but overall, nothing else.

I had to mod the rack since the old topeak rack was not cutting it. It's not pretty much reinforced. I hit very bumpy roads on my daily 46 mile commute and no problems. I do worry about the bolt holding the rack since now that is the weakest point. Not that I did not get stainless steal solid rod which I should. hopefully the rust will not kill the support rod.
View attachment 5
View attachment 4

Overall 500 miles in 2 weeks counting going to work and local testing on this new motor.

Front view,
View attachment 1


Rear view
View attachment 3
View attachment 2

Feel Free to ask anything about this bike if you want. I will answer ASAP.

I am looking forward to my full suspension mountain bike build with HS3548 and a 74V13.5Ah Lipo battery. I will try to get pictures and reviews up as soon as everything works out.
 
That's amazing.... your ebike looks like and reminds me of my 1st ebike build. Black overall color with black fenders. You even chose the same black Topeak rear rack and bag with deployable side panniers. I started off with a rear hubmotor but I changed to a front hubmotor because I wanted to see if moving some of the wieght distribution towards the front would improve the ride. That's why I have it shown here with front hub. That was a big mistake... It sucked big time! It made turning twice as difficult and totally ruined the ride. I've stayed to using just rear hubmotors since.
Rover1.jpg

And in those days I was still only had direct drive hubmotors. After I got my 1st BMC geared hubmotor and learned how much more torque and acceleration they have, and that they freewheel, I never went back to DD hubmotors again. You made a wise choice with the geared hubmotor.

I got a couple thing to mention that might help you. First thing is about your Topeak bag and rear rack. Topeak has a nice rail-mount system that allows you to slide the bag on and off the rack. It was and attractive feature to me and many other ebikers because you can lock up the bike and slide the bag (and your expensive batteries) off the bike and take it with you (to maybe recharge or whatnot). Only thing is having 30+ pounds of cargo and mounted to a hardtail bike might lead to problems. Here's what happened to me. The constant pounding of that heavy load on the top deck of the rack eventually bent and warped the rails on the rack. Here's how badly warped my rack looked like after about 3 months.
TopeakRack1.jpg

The bag would not slide on an off easily anymore and it soo loose that it had a slop left and right. The bag eventually got so loose that every time I'd hit a bump I'd hear the bag lift off and slap the rack hard. It was like a sledge hammer pounding on the rack every time I hit a bump or pothole. The vertical strut member on the rack finally cracked and I ended up replacing the rack with a stronger one made by Zefal that was rated to 50 pounds. Then I eventually drilled 2 holes at the bottom of the bag and bolted it permanently to the deck of the new rack. I also put 2 layers of spongy carpet padding at the bottom of the bag so that the heavy battery pack was now floating on a nice cushy pad.

I noticed you said you're not pedaling most of the time. Is that because you're still using the original small chainrings on the bike and your legs would be spinning too fast at your regular speeds of 25+mph? If so you might consider putting a larger 53T chainring on the front and a smaller 11T on the rear so you can keep up pedaling comfortably with the motor.
 
Thanks for the reply. And the bike looks like a clean build. The only thing I recommend is front suspension, but I think it will not work out with your front hub bike since it's not recommended. yeah I did my research on front hub and it did not appeal to me. There were all sorts of issues. As for geared vs gearless, I am getting a HS3548 soon and will be mounting it on my Full suspension mountain bike. I will have a review soon after I get that working. There are pros and cons for both. But I do like the light weight and freewheeling property of the geared hub motor.

Yeah My rack is bending likes yours too, but so far it's not a problem. It's really the point of connecting on the bottom center leg that bends. I did not get a chance to take a picture of the bent rack without the steel bar reinforcement.

As for pedaling, I rarely pedal because I do not want to get into work all sweaty. I think on the last ride to work, I never pedal at all. I just went slow climbing hill and watched the power input. No sweat at all. : )

As for the gears ratio thing, I can assist is all the way up to 43mph. At that speed, I am pretty much at max pedaling rotation speed. I would not be adding anymore speed if I did pedal. I have tested this because I always hit 50mph down a hill on the way to work. I usually average 33-36mph on flats so if I wanted an extra boost in speed, I can always pedal. But it's really hard to gain much speed after I pass the 38mph mark. I have to really break a sweat to get it to go any faster.
 
may want to consider looking into the crystalyte triangle bag. It would fit in your bike well and shift some of the weight forward, making the bike handle better for sure.

The falconEV bag may fit your center triangle too. If that's a 19" frame anyway.
 
Yeah i have considered the triangle bag. However it will take away the stealth look. Moreover, I would need to cut open my 48V30Ah battery and shift the cells around to make it fit in the bag.

thanks for the recommendation though.
 
Some more updates:

I am planning to migrate to Lipo for this setup. Therefore, I have placed an order for the Falcon EV Triangle bag. I will probably either retire this 48V30Ah LiFePO4 battery or maybe reuse it somewhere else or maybe just keep it on my bike so I have super range.

I will keep you guys posted on how it looks. Even though the bag is for 19 inch frame, I am hoping that I can crush it a bit. I looked at the crystalyte bag, but I was worried that i would not be able to hold the long 10s nanotech battery stick.

Final Lipo battery should be:
51.8V*27Ah. Though I will probably just run it to 23Ah or 24Ah at most.
It will consist of 6 37V4.5Ah nanotech in parallel in series with 6 14.8V4.5Ah nanotech in parallel. Total weight for this setup even with connectors is around 20lbs I believe.

Another update is this setup is rain-proof. Since my Topeak bag has the rain cover, that covers the battery, controller. The motor itself is weatherproof and a bit of rain did not harm it. The CA and throttle are all OK in the rain. This is confirmed twice riding in rain.

Overall I think this current setup is really reliable and probably more so once I move to Lipo and do not have that 30lbs battery on the rack and hitting potholes.
 
Wow, amazing thread. Thanks for including all the detail. Yes, it was very comprehensive for sure. It's like we could build our own exact replica with all the detail you included (not that we would). Congrats on the build. Ride safe.
 
mvly said:
Even though the bag is for 19 inch frame, I am hoping that I can crush it a bit. I looked at the crystalyte bag, but I was worried that i would not be able to hold the long 10s nanotech battery stick...

I run a Falcon EV bag with 52V 11.5Ah A123 in my triangle. It fits in the 20.5" frame nicely. I was also able to squeeze it into the Raleigh C40 that I used for my first build, and that was a 17.5" frame. You should have no problem fitting the Falcon in a 19" frame, unless the top-tube angle is too much.
 
Ok some more updates:

1) Migrated to Nanotech Lipo
-New configuration: 37V4.5Ah x 5 + 14.8V4.5Ah x 5 = 51.8V22.5Ah Nanotech. I could've fitted more batteries in there, but it was getting tight and I would have to put some pressure on some lipo stick. Knowing how unstable lipo is, i chose not to cram anymore in. Moreover, one of the extra 37V4.5Ah stick had a weak cell, so I decided not to put it in to drag the other cells down.
I chose 14s to get the most out of my BMC 50A controller. It is rated up to 59V I believe. 14s Lipo hot off the charger is 58.8V. However I only charge my Lipo to 4.1V per cell so it is really 57.4V hot off the charger. The 51.8V22.5Ah Lipo weigh in around 14lbs to 16lbs including the all the connectors. This is a major upgrades to the previous battery which was 32lbs on the rear rack.

2) Installed the FalconEV bag. Surprisingly it fits. I had to crush it a bit. See picture below. Now the weight is in the center of the bike and it is so much better to ride. I do not fear bumps anymore after moving away from my 32lbs LiFePo4 battery in the rack. See image below.

3) I now carry the charger setup in the rear topeak bag. I use a PRC500 + 2 icharger 1010B+ each at 7.5A charge rate to charge seperately the 10s and the 4s nanotech parallel pack. The 7.5A is pretty much the max the PRC500 can handle. Base on my calculation, it was around 450Watts draw from the PRC500 which is rated for 500Watts.

OK here is the evolution of my bike:
1)
Full Bike Converted.jpg
This is the original build. I still had the 36V20Ah LiFePo4 battery in the center of the bike. The 48V30Ah LiFePo4 in the topeak bag. This bike was well balance but everything was heavy. At this point, I did not reinforced the rear rack and i went through 3 racks. With this setup, I went 45 miles round trip at full throttle and still had battery left (48V battery was at 20% and 36V battery was at 40%).

2)
IMG_2556.JPG
I basically removed the 36V battery because I didn't want to hassle with plugging and unplugging the switch to interchange the voltage on the controller. Also I figured that I didn't need the 45miles max speed range. Finally I really like the stealth of the bike because no one would have expected it to be an ebike. Everything would be hidden.

3)
IMG_0507.JPG
This is the current build. It works amazingly well. It rides much better than the previous 2 after the battery weight reduction and balance. The whole bike weighed in around 85lbs.


Here is the close up of how many lipo stick I was able to install.
IMG_0495.JPG
Note the long stick on the bottom and the short stick on the top. Long stick = 37V4.5Ah. Short stick = 14.8V4.5Ah.

I also made some external connectors to the controller from the battery so that I don't have to open the battery bag every time I charge. Now the only test left to do is to see if this Falcon EV bag is waterproof or at least water resistance. I will try to ride in the rain one of these day to test this fact. Version 2 build was OK to ride in the rain for sure.
 
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