Thread: CT70 runs...for 1.5 seconds...help!

I just picked up a CT70 that has not ran in a few years. Gave it a good once over. Replaced the points (they were toast), adjusted the valves (closed up a little), cleaned the carburator and replaced the o-rings. New battery also.

I have good spark, I know fuel is getting to and through the carburator. I kicked it over and it runs very briefly before dying. It does this very consistently.

I took the carb apart...again and noticed the slow jet is either clogged or does not have a hole going all the way through it. Does anybody know if this is the case? What function would it have other wise? Could this be causing my starting problem?

Any suggestions would be greatly appreciated. I'd really like to get this thing going. Can't wait to start riding again.

you will know if you have a fuel problem if you drip a little gas in through the spark plug hole and it runs for a while.

i am not shure if the idle jet is causing your problem but it would not be hard to shoot some comressed air threw it to clean it out

Steel tank or plastic?

If it's steel than you're probably clogging the pilot jet consistently. I recommend replacing the tank with a plastic one off ebay and installing new lines. Clean the carb and installing new pilot and main jets.

Clogged pilot jets are very common on these older bikes. Starting and idling effected by a clogged pilot jet.

The low speed jet or pilot jet should have a small hole thru it also when you take it out it has some small holes on the side of it if these are cloged it will start and die like yours is doing, hope this helps Grant

ya what he said. any rust or particles will cause this same problem. mine did the same thing. ran super then bogged after a few. it was rust particles. carbs are picky.

I see alot of posts concerning clogged jets,why isnt anyone using additional filters to stop the sediment before it gets that far,Its surprizing how much trash mine catch