i want this it's a good price and i'll probably get one http://www.bicycle-engines.com/dual-brake-twist-throttle-p-148.html
Don't waste your money. It is a great idea but it just dosn't work.This came with my engine kit. I fiddled with it for more than 2 hours. You just can't adjust the brakes. After some thinking I figured it out. It would work great
if both brake cables wrer the same length.
later/ mikey/bikey mike