Just acquired a TY80 which was running ok but needed new clutch cable. Have fitted this but engine revs like mad and wont shut down, anyone got any ideas?

Hi, it sounds like that you have trapped the throttle cable,check the routing of the cable and that it is noy fouling the throttle cable,make shall that the throttle cable is sat in the top of the carb .

Regards Paul

The TY80 I bought for my son did this,thought for a while the throttle slide was sticking - not so,it was pulling in air from the main bearing seals.I did a complete rebuild on the engine with a genuine piston/rings etc,now runs a treat.

Thanks for reply Paul, I have checked the cable is free as we had the tank off, it certainly looks OK, my thoughts were whether it could be something to do with the throttle slide, but we have not done anything to the carb.

Hi yep it definately sounds like drawing air via crankshaft oil seals if you can get it to tick over take out oil filler/dipstick andif it revs its nuts again hit kill switch and strip and fit new oil seals

Cheers H

If it was fine before the cable change then the throttle cable/carb has been disturbed

Dave

I would bet on the cable routing. Do you have slack in the housing when supposedly at idle? if not, the cable is lifting the slide.

Also check the slide. On one side (I think right side) there is a brass pin in the carb body. The slide has a slot that fits on the pin to index it as it moves up and down.

Been many years ago, but on two of mine, the pin worked its way outward and allowed the slide to turn slightly and bind on the pin.

Solution: Lift the slide out, tap the pin gently inward so the outside is flush with the outside of carb body, and put a drop of epoxy on the outside. Clean and burrs on the slide, reinstall and it should be good.

kcj