Control each wheel independently. Trigger control in each hand. Just an idea, could be useless, just throwing it out there. If you could come up with some sort of mixing type controller you could do it with one joystick. When you turn the it automatically slows or locks on wheel depending on speed and turn sharpness.

Probably easier to do it mechanically. The rear wheels could be attached via a differential with disc brakes on each wheel. Then, just apply brakes to a single wheel to turn in that direction. Apply both to stop.

USB 3.0 implants directly in the brain. Meld the man and the machine.

The other upside would be if you ever got to be a PITA, we could just root you, re-format and flash a new ROM.

Otherwise I like TX's idea

modules installed
 

Got the modules installed last night and went for a night run! WOW what a difference the lipo conversion made. First ran at 66% current limit(200 amps) then in full power mode(300 amps at 74 volts in theory, though in unlimited mode it bursts higher amps). Full power mode is downright scary - I seriously am in need of a better throttle(only 90 degrees of twist makes for a twitchy ride) - I would like to get a 120 degree throttle to add some resolution for sure. The gearing tops it out at around 43mph and it gets there in a hurry! At 25, if you grab full throttle, it will throw you off the back unless you let up quickly - feels like a kx250 when it hits the powerband! I dialed in a progressive curve and went back to 80% current limit(240 amps) - theoretically limiting the power to around 20HP, which is plenty for a 150lb machine. I am totally psyched!
Oh...before i dialed back the power, i managed to rip the primary drive belt in two(hanging off the foot peg). I hope to get some body panels done this week to cover the batts/wiring a bit. Here is a picture:

pictures
 

the bike and the broken belt

Sounds great, but no pics.

nevermind. I see the pics now.
.

Yeah, I clicked "post" a bit soon! That belt had a small blemsih on it when I got the bike, but it held up to the 200 pound machine on lead power without issue. It lasted about 10 minutes in its first daylight run today - thankfully I wasn't far away(had to push the bike home of course).

Sounds like you need an exponential throttle control so the throttle is a bit more manageable at the start. If it's just a pot, you could try a "linear taper" type (these are logarithmic - not exponential, but similar curve).

It has a 0-5k pot throttle(Magura twist - very common). I would love a better throttle, but aside from building one there doesn't seem to be many other options. IMO, 90 degrees is a bit stingy - I have at least this much on every gas bike I own, but with 5 or 6 speeds, the actual "speed resolution" is 5 or 6 times better. Certainly 120 degrees of twist would help, as would an exponential throttle - they just don't exist or I don't know where to get one.

Hey mike, nice bike. What is the range on the stock bike? What is the expected range on your battery conversion? I love that you used basically off the shelf batteries, makes fixing and replacing components easier. If i ever lose enough weight, i'd like to get a E-bike for commuting to work. I would look into this setup, as i know the guy doing it is one of the best in the area of engineering and ergonomic and wouldn't sell anything that either doesn't work , or he wouldn't use or ride himself.

One thing please, If you do get into the E-bike area, please don't let it overtake the rc part. Would suck if RC-Monster didn't do RC parts anymore

Unfortunately, I don't know enough about how all these throttles are built to offer good suggestions. A pot is simply a wiper arm that scrapes across a resistor giving variable values at the wiper arm contact, so it should have virtually infinite resolution. I wonder if the controller is your limiting factor? It might apply steps of output based on different resistance input thresholds (basically a really low-resolution A-D converter :smile:). Simple testing with a meter at the throttle output should tell you what it's doing, but testing the output of a BL controller to see what its resolution is is a bit more difficult to measure. If it IS a matter of 60* twist not having enough resolution, maybe retrofit a different 5k pot in there? I would be careful about reliability though as the mechanical action of that wiper arm "scraping" does cause wear and "noisy" actuation. I'm kinda surprised digital encoders aren't used to avoid that.

While I agree with you, it is obvious more and more manufacturers are coming out with off-the-shelf electric products, so the custom side of things has to be taking a hit. It's not like the old days where if you wanted an electric toy, you basically had to build it. I think maintaining current custom items is nice for those who still like to tinker, but I can see Mike having to diversify to make enough green to keep the lights on.

I am not getting out of RC anytime soon, Larry - no worries, there. Before RC was my job, it was my hobby. Now that RC is my job, I have simply expanded my other hobbies to keep myself from going off the deep end. As Brian said, what used to be custom stuff is becoming mainstream - at one time I was the only guy making electric conversion stuff but the big dogs are in the mix now(major manufacturers). I am not dumb enough to think I can compete on price with the industry giants (on quality or innovation I try to hold my own, but volume dictates price and I have got nowhere near the volume of the big dogs). I also make my parts here in the USA and therefore pay my help fair wages - it simply costs me more to produce parts. I could go to Asia for parts like everyone else, but I would rather not.
As long as I can stay afloat doing what I like to do, then I am rich(may never be wealthy, but I am OK with that). I may dabble in other areas to stay in business as well as simply expand my knowledge - I have always been into motorcycles(street and dirt) and have always owned at least one motorcycle my entire adult life - this is an obvious avenue to explore, just like RC was 8 years ago when I went into business. :)

BrianG - I agree that a pot is theoretically infinatly variable within its travel, but controlling 35HP in rocky terrain with only 90 degrees of twist can be quite the challenge - remember I am using the same hand to hold on! The controller itself may be part of the problem, too - I just know there has to be a better system than what i currently have. This is not to say what i have isn't good - in fact it is quite awesome in most regards - just that overall control could be improved upon.

How about adding some resistance (making it physically harder to twist, not electrical resistance) on your current twist throttle? I'm thinking that making it a little harder to twist will reduce that twitchiness, similar to how the steering control works on a Spektrum transmitter.

What about a thumb-style switch? While shopping for e-bikes, thumb and twist seem to be two main options. I know from riding my mountain bike (pedal only, no assist), I greatly prefer thumb gear changing exactly for the reason you state.

After thinking a bit more, do you think that adding more than 90* of twist action will cause excessive wrist articulation making it even harder to control?

You could attach it to a spectrum RX and have the "other half" control the throttle whilst you ride it :diablo:

Mike that looks AWSOME.