Decent, progressive throttle?

[Jimbo]

Hi all,

I thinking of doing a Crystalyte HT build on my Trek Fuel full sus. From what ive read this is a bonkers high torque motor, which is just what i want for some trail hooning. All the throttles ive used (admittedly only two) have been pretty much on/off - fine for a low power setup but bloody dangerous with an HT i think. Im not keen on wheelying into the nearest hedge, so what do the pro's use?

 

[dogman dan]

Slower winding motors. I get much better throttle response at 72v with the slower winding, since top speed is only 25 mph. Less amps too, so when I grab a 1/4 throttle, I'm not grabbing 20 amps. More like 5.

I wish too, that throttles had a lot finer controll built in for trail riding. It's all finesse on the trails I ride. Mo power would just launch me into huge cactus.

 

[Jimbo]

25 mph at 72V with a Crystalyte HT??

I'm not sure how a PWM throttle actually works (assuming its not a big potentiometer) can any boffins educate me?

off to do some research......

 

[iovaykind]

Wouldn't a three speed switch make the throttle more "progressive". It would end up having better resolution, and on hill riding you won't be switching speeds that much anyway. I think basically how the three speed switch works is that if your throttle is 1.2-4.2v range, setting 1 would have a resistor that brings it down to say a max of 2.2v, which means it won't catapult you every time you hit the throttle hard. The only downside is a limited top speed, until you switch speeds.

 

[dogman dan]

Sorry, to clarify, I'm using slow winding 9c motors. My dirt riding bike is currently running a 9 continent 2812 winding. Super slow, but perfect for the type of ride I do. I really don't want to fly over the bars into rocks and cactus ANY faster. Often, I'm riding about 12 mph. That speed would fry most normal winding hubmotors unless I was pedaling enough to keep the watts below 300. Thats no fun, I want to ride no pedal, and use 1000 watts, at 12 mph up steep hills. The really slow windings can do that.

As a side effect, having a narrow range of speed gives me finer controll over the throttle. My street racing bike ran 120v, on a 2807 winding. It's throttle was like 0,0, 0, 25mph. Near impossible to hold a setting below 25 mph. It's throttle range was like 25 mph-47 mph. Very awkward, you had to give the throttle teeny tiny blips to go slow in the pit area.