Sunlova e-bike kit on Trek 3700 MTB

[Pob]

I have virtually finished my electric bike conversion using my Trek 3700 mountain bike and a kit from Sunlova. There are things to do like change my left hand handlebar grip and sort out a front mudguard and then there's a rear light................. work in progress is what they say. I used stainless allen bolts wherever I could and used Vaseline on electrical connections, grease and ACF50. Fresh v-brakes and new front headset bearings and new suspension forks - set on stiff setting. The idea was during assembly to help keep moisture out and prevent any gremlins by trying to do things properly and overhaul my bike as I went. I think the kit is good, things were fairly well made and I haven't had any issues apart from the bulky pedelec sensor which I don't want to use yet anyway. When I do fit it I shall see if I can modify it and make it a neater fit to my bike. My Trek has an alluminium frame and was not a heavy bike to start with so I am pleased to say with the motor and battery it is still not over the top for weight. Once the ice clears I will give it a thorough test ride.

I should take the bike outside with a blank background and take some more pictures as there is so much in the background in my garage that it's not easy to see what is what

 

[Pob]

Here's the battery showing tester LEDs It has an on/off switch behind the bike seat so easy to reach while riding the bike.

Here's the throttle and switch on handlebar.

 

[Blew it]

.....and standing on the red carpet ready for it's public debut, very appropriate.

Looks good so far, I hope it runs well. It's a complete bike now, why not nominate it as your 'Kit bike of the year' in Aldby's thread.

Regards
Bob

 

[eddieo]

Nice job, but some white tie raps and some sticky clips may give a less intrusive cable management solution

Cable ties fixing | Tie wraps fixing | Cable tie wrap adhesive pads

 

[Marky T]

Hi Pob,
Looking pretty smart, keep up the good work.

Marky T

 

[Pob]

Thanks

Was thinking about drilling a hole in the frame and using grommets to pass the cables through the frame at some point - I will see how it goes.

The Red is my motorbike hydraulic lift on our ex-living room rug - save the knees and back when tinkering.

 

[Pob]

Well been out on a test ride and I am chuffed to bits with it. I only went a couple of miles but most of it was hilly. I don't have pedelec sensor on so I just rode the bike as normal and opened the throttle for help to either add speed on the straight and level roads or for extra help to get up the hills. It works really well with plenty of assistance from the motor, I was able to just casually pedal along with the throttle fully open and climb steep gradients like I was on the flat - very impressed. So much so that if this is just as good on a long journey I am going to have a re-think about whether to sell my motorbike and invest in a seriously powerful off road MTB with the money.

 

[NRG]

Nice looking conversion

 

[jayuk]

Hi Pob

Bike looks really good!, I used to have one of these kits from sunlova & im now moving up to the more powerful version the BPM hub. Its all being put together for me as we speak & should be with me early on in january. the new kit will be able to reach approx 27mph. the sunlova kit is certainly good for the money!, the new style battery looks a little slimmer than the old style too. I was also thinking about channeling the cable through the frame but am unsure how this would affect the strength of the frame although this would only be for the throttle cable.

jay

 

[Pob]

Thanks Jayuk, what are you having built excatly? I am starting to think about a rugged electric MTB that has a long range and good power -for off road. I have a van and would take the bike in my van somewhere then ride through some trails and van the bike back so legalities are not an issue. I am interested in something that has more power, and say 50km ish range in a tough mountain bike set-up. I have ridden motorbikes for years - on and off road but they are frowned on by many people when used off road (I am sensible and courteous to horse riders and walkers) would be great to go off roading electrically! Any suggestions?

 

[Deleted member 4366]

50 miles with high power means huge batteries, so that it'll look more like a motorbike. It might be more noticeable on the road by the boys in blue. Have a look on the Endless Sphere forum wher the Americans do what you suggest.
Jay. What batteries will you use? I've got a BPM and three 10ah lifepos, but I'm not sure if they give enough current. I've just bought some LiPos to try. Does anybody know if a 10ah lifepo will suffer damage at 15 amp continuous with bursts at 25amps?

 

[jayuk]

Hi Pob

i'm having a bafang 8fun BPM hub motor laced into a black rim with black spokes to match my front wheel & having an A123 9.2ah 48v battery built, As my journey is only approx 8 miles i have no problems with the battery capacity. I had a search over on the Endless Sphere forums & got put in contact with a guy called Cell_man & he is supplying me the whole kit direct from china!. Although it is costing more than the sunlova kit i will have a better more long lasting battery & a faster bike with hopefully twice as much torque as the original kit i had (the same as yours), No doubt there is cheaper places to get this motor but not how i want it built to match my bike, plus theres nothing lost in translations as cell man is english!.


Hi d8veh

my battery will be 9.2ah 48v A123 on a 25a Infineon controller with a 30a BMS
bpm motor is a code 10 36v (running at 48v)

 

[NRG]

50 miles with high power means huge batteries, so that it'll look more like a motorbike. It might be more noticeable on the road by the boys in blue. Have a look on the Endless Sphere forum wher the Americans do what you suggest.
Jay. What batteries will you use? I've got a BPM and three 10ah lifepos, but I'm not sure if they give enough current. I've just bought some LiPos to try. Does anybody know if a 10ah lifepo will suffer damage at 15 amp continuous with bursts at 25amps?

The Turnigy Lipo's? The come rated for 20, 25 or 30C..... Also at 40 now I think..... So will easily supply that current, did you see the truck starting thread on ES using a single pack? Impressive!