Hi, ive just assembled a 70cc bike with a speed carby and it works well for a minute or two then just gradually loses power till it stops, heat problem maybe? any sugestions would be much appreciated please? 
losing power
- Thread starter chelseapub
- Start date
runs for a min or 2? how? idling or riding?
if riding, while going slow,cruising, or WOT?
fuel starvation possibly.
if riding, while going slow,cruising, or WOT?
fuel starvation possibly.
it idles well and runs well for a minute, (this motor has just been started for the first time) then its like it starts running out of fuel but evenly rather than just conking out in surges, if i let the throttle off and start accelerating again it gets back up to full revs but the losing power gradually begins again till it stops. i'm not a mechanic so can only describe as best as i know how to sorry.
yesits 2 stroke and i'm mixing 20;1 for the first couple of tanks, this is ther 5th bike ive put together, i might try a stansard carby on it and see how that goes, the beauty of having spare parts helps with the process of elimination hey
we are thinking it is a fuel problem. not a motor problem.
either the carb isn't getting a good flow of gas.
it happens often.
either the carb isn't getting a good flow of gas.
it happens often.
I agree. That's what it sounds like. It's a common problem. When it starts to run crappy try loosening the gas cap.GearNut might have it right?!
thanks guys, i replaced the speed carby with another speed carby, same problem then i tried a standard carby, it works! is there an adjustment i can make on the speed carby to make it work?
I'd check the pin in the carb, if it's starving you're running too lean. It could also be too rich and bordering on flooding. Try moving the clip on the pin a notch up or down (most start at center by default).
