I'm going to be a while getting the current readings I'm afraid, I've got to get through my exams before I can do any major programming/design work. Will keep you updated though/ I suspect that if I can sort my mechanical issue (see below) then it'll be around 100w lost in the CVT (belt vibration, slippage, etc) and a fair bit more in the motor due to the fact that it's running right in the upper end of its RPMs all the time. Not sure though, will definitely be interesting to see.
Weight savings - the exhaust was pretty meaty, about 5kg sounds right. The cylinder, air box, fuel/oil tanks, flywheel/alternator and carburettor are another 5 or so kg, but the batteries are going to be pretty heavy to get a decent range so I'd estimate it'll be around stock weight when finished - I don't have the final pack yet though. I've not finished reassembling and I didn't weigh before starting, so I can't give you any better numbers than that, I'm afraid. I'll make sure that I get the weight when it goes in to get tested, but I don't have access to any decent weighing equipment.
I butchered the oil pump to fit a potentiometer (so I could use the original cables and throttle), ran that straight to the Arduino ADC pins and mapped that to a pulsewidth with a simple map() function (I used the range 1000ns - 2000ns but you'll probably find the ESC will only actually operate between the range 1200ns and 1800ns or so - depends on the ESC though, so play around until you get it working smoothly. My ESC didn't run using the writeServo command, only the writeMicroseconds command for some reason, probably relating to the pulsewidth). Every 50ms it checks the pin, maps the value to a pulsewidth, checks the brake cut-out and sends the appropriate pulse to the ESC. Start-up is currently as simple as connecting the batteries through a resistor, listening for the ESC beep, then connecting the high current lead - I'll probably add a safety "twist to max whilst squeezing the brake to arm" feature at some point but for now it works fine.
Might use this eventually:
I noticed a mechanical issue on the drivetrain last weekend whilst playing around with some other bits - the splined shaft holding the variator on had slipped slightly in its bearing (was hammered into place, obviously not well enough) and was not spinning true, which was creating some horrible vibrations and "stalling" the motor/making the ESC lose sync, I'm not sure which. I'm going to see if I can re-align it in-place this weekend, if not I'll have to take the motor out and try it again. A bit of a kick in the teeth since it was working pretty nicely the last 3 times I tried it, but it hopefully shouldn't be too hard to correct.
I'm just going to try the variator rollers for now, if I need more performance later then I'll probably go with a gear-up kit. I'll probably end up using either no springs and changing how the throttle responds at low speed (increase accuracy at low range - exponential throttle map?), or buy the lightest springs I can find. The gear-up kit might well prove useful though, if the variator mod doesn't help enough.