Prolog, the plan, and some recap

Cut to the chase:  Finale

In this blog I aim to document the building process of my second electric bike.

Disclaimer: This setup is quite powerful, and therefore FORBIDDEN by law to ride on road, it is meant for off-road use only. This blog exists for demonstration purposes alone and anything you do is on your own bloody responsibility, bla bla bla...

My objective: A high-end bike (DH frame), with a decent & reliable system that can deliver 40-60 KM/h, with short periods (like 2 minutes) of ~70KM/h. Most of the time I'll be cruising ~45KM/h, but I'll want that 70 for whenever I have an option to ride that fast.
My terrain is mostly flat. I plan to use the bicycle as my primary vehicle to work & back. Each way is ~30KM and I can charge at each end.

The following recipe fits that bill (and then some):

• Bike: Downhill/Freeride bike with space in the triangle.
• Motor: Crystalyte H40 Cruiser from Ilia @ebikessf.
• Battery pack: 24S 15Ah of Lithium Polymer high discharge (5C).
• Controller: LYEN Edition 12 FET 4110 MOSFET Extreme Modder Controller.
• Charger: Cellpro Power Lab 6, 1000w.
• Power supply: Some 1000w power supply...
• 3-speed switch, cruise control, multi switch (for lights and bike's on/off), battery alarms.
• Cycle Analyst V3 (with the temp control).
• Wires, connectors, solder, lots of good tools.

This kind of setup should give 44KM of range @ 50KM/h, and an amazing climbing ability even for tough hills, with a maximum of 135nM of torque. The controller will transfer a peak of 5kW to the motor. Not bad :)


Before beginning, a small recap:

• About half a year of research on motors, batteries, etc., focusing on what I really want, researching more ... Started with a 1000w motor in mind, then thought that two 1000w motors would be even better, and finally went back to just one motor that's more powerful than the previous two together - 3.5kW continuous. All in all hundreds of hours' worth of reading. The best read of all is www.endless-sphere.com, THE place for electric vehicles.

• 22/10/2013 - Decided on the Crystalyte H3540 motor from www.ebikessf.com (highly recommended). But found that it's back-ordered, so went for the yet beefier & more powerful 4040 :

• 06/11/2013 - Settled on a used 2008 Specialized Demo 8 as base. Decision based on MadRhino's (from the endless-sphere) very successful experience with converting this bike.