Speedfight wont rev

Put a viva lump into a speedfight, (same engine), put a 3 wire stator on to suit the immobilised loom that was on the speedfight, it ran fine while it was in the viva frame, and then once i had done the stator, it would start and then wouldnt rev, have tried 3 carbs, engine runs with all on but still doesnt rev, wheel doesnt spin yet it wont die out from the revving, so its not a carb problem, im thinking it could be a woodruff key? as the one on it didnt look much use, i also tried a couple more 3 wire stators, then the original 4 wire one to the viva loom and it still didnt change anything, does anyone know what it could be? thanks alot,

 

you need to reset the immobilisor from the sounds of it.

if the immobilisor has been tampered with they will start but not rev

 

oh no, its not the immobiliser, already gone down that route, tried the 4 wire non immobilised loom with basic CDI, two good immobiliser sets which have been ran on other bikes to test, and an immobiliser bypass, usually if the immobiliser starts the engine but wont rev, the bike will cut out from the slightest bit of throttle, this can take as much throttle as you can givei t, but the wheel refuses to move, it will spin slightly, more than just when its ticking over, but definitely wouldnt take any weight on it,

if that makes sense?

 

My mate had a similar problem on his SR50 it will tick over spot on but the slightest bit of throttle it dies, right?.... well it turned out the metal bit on his reed block had snapped, check yours im sure its that it sounds exactly the same

Hope this has been helpfull :good:

 

nah, you can full throttle it, it just wont do anything and bog the engine, itll still run when the throttles held on full but il check reeds out asap

 

is the slide connected properly to the cable in the carb?

is the cable itself snapped?

 

:good:

 

nope, tried another cable too, and the slide etc is all fine, one cable was off the previously running bike and the other looked fine too,

 

sort that woodruff key first get the stator off and redo it properly there pigs when the woodruff key is fuck. cut up an old washer if you have to

 

Instead ofI'm aking a new post, il post on this as I have the same problem.

I have standard 50 engine with sports exhaust, upjeted from 72 to 80 and stock rollers. Ran perfect for an hour with noticeable increase in power, but the throttle got stuck open due to a non lubricated throttle cable which is now sorted. I started her up and she Idles fine but as soon as you twist the throttle it cuts out. There are no exhaust leaks and the air filter is all there (airbox and pipe) . So what I'm confused by is the fact it ran fine for an hour and now it won't rev