Road bike conversion for £300

[Einsgruber]

Just sharing my first creation.

2014 Boardman Pro Hybrid
36v 350w Motor
https://www.ebay.co.uk/itm/264256829672?ul_noapp=true
36v 5.8amp Battery
Motor controller
https://www.ebay.co.uk/itm/Electric-Bike-6-Mosfet-Controller-Brushless-Gear-Dual-Mode-36V-250W-350W-500W/254213517220?ssPageName=STRK%3AMEBIDX%3AIT&var=553595586641&_trksid=p2057872.m2749.l2649
Display
https://www.ebay.co.uk/itm/UK-Smart-36V-48V-KT-LCD3-Display-Meter-Control-Panel-For-E-Bike-Electric-Bicycle/401792203755?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
Throtle
https://www.ebay.co.uk/itm/Thumb-Throttle-Speed-Control-for-E-Bike-Electric-Bike-Scooter-3-Wires-Universal/223218221525?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

I bought the majority of components on ebay and I can post a full shopping list if anyone is interested.

First of all this was an absolute nightmare of a learning curve but well worth it...so much fun. I cant tell you how many cable ties I've used!

I built the rear wheel from scratch using a Mavic XM319 rim with x36 12g stainless steel spokes
upgraded to 185mm disc rotor to fit around the hub, however, had to grind away 2mm of my mounting bracket to gain some extra clearance on the frame

All the wiring just about fits into a small aluminium drinks bottle and the battery I've fixed to the frame using the bottle mounts and 50mm half coupler clamps.

I've only ridden it a couple of miles and its fast.. under her own steam she'll do 24kph but with me peddling well let's just say it nippy.

Before ...

After ...

 

[dustNbone]

Looks nice and tidy, good workmanship.

My only concern would be cooling the controller, there isn't going to be much if any airflow over it inside that tube, and they do throw off a fair amount of heat.

Estimating 85% efficiency, that's 15% of the watts going in to the controller that it's going to need to reject as heat via it's case, so picture a 60Wish light bulb inside there. Just something to keep an eye on.

Enjoy your new ride.

 

[Einsgruber]

You're right I had considered that it's somewhat cramped inside the bottle I'll make sure to keep an eye on it.

I can always take the lid off if it gets toasty haha or paint it with heat changing paint to indicate it's about to catch fire

Thanks

 

[qwerkus]

Nice battery + clamps. Did you make them yourself ?
If you want to get rid of the cable binder holding the bottle, you can just make a metal plate of 15cm that reaches all the way down to the 2 holes on the seatpost.

 

[bakaneko]

You can also buy the 36V 4.4aH (~150wH) scooter battery packs that some of us here use and build up a big battery bank with time and distributed monetary investment. The price is 25-45$ per pack and the cells perform well for 36V systems like yours. They come with XT60 connectors. I use mine in serial for 72V but they are not for performance bikes (>2kW).

Make a nice enclosure and space for more batteries and you can go forever especially with the efficiency of road bike tires. I started with 2 packs and a 36V 500W hub; now I am at 8 packs with the 72V Cyclone and a gas generator serial hybrid.

https://www.ebay.com/itm/36V-4-4Ah10S2P-INR18650P-Li-Ion-Battery-For-Balance-Scooter-Board-Free-Shipping/223478497910?hash=item34085b4276:gaUAAOSwSw1cg-MY