2 stroke woes,help needed !

[dugless]

I just rebuilt an old twin 2 stroke

I have started the bike ,and it started and ran ok etc,but the rpm was sitting up around 4000 ish on tickover..

Im adjusted the tickover down which helped,and then shut it off.

Now ,I refueled bike but when I tried starting it there fuel coming out of the right overflow,constantly pouring out until I switched it off at tank.

so I assumed there may be a problem with the carbs,so I had a spare set of carbs I stuck on,same thing ? fuel coming out of one side lower overflow and higher overflow with a collection of fuel in the main body.

the slides and needles are going up and right down perfectly,theres something not switching the fuel of on the right hand side carb,any ideas ?

I'm not to clued up on floats,but it like its stuck ? , but on both sets of carbs on the same side !??

please help....

[ultimasimon]

Sounds like a float problem. Check to see if the float hasnt been put in upside down. I had that on a Honda CB100 I bought. Also there is a drain screw at the bottom of the bowl, I would check the seal on that too.

If the bike ran at 4000 and then died, it sounds to me like fuel starvation so I would defo suspect the float levels first.

Have a look at the spark plug to see if you can see whether it is wet or dry immediately next time you start and stop it. The other thing I would check is that both the inlet manifold gaskets are good and not leaking.. come to think of it check if they are there at all

[morrisman]

dugless said:

I just rebuilt an old twin 2 stroke I have started the bike ,and it started and ran ok etc,but the rpm was sitting up around 4000 ish on tickover.. Im adjusted the tickover down which helped,and then shut it off. Now ,I refueled bike but when I tried starting it there fuel coming out of the right overflow,constantly pouring out until I switched it off at tank. so I assumed there may be a problem with the carbs,so I had a spare set of carbs I stuck on,same thing ? fuel coming out of one side lower overflow and higher overflow with a collection of fuel in the main body. the slides and needles are going up and right down perfectly,theres something not switching the fuel of on the right hand side carb,any ideas ? I'm not to clued up on floats,but it like its stuck ? , but on both sets of carbs on the same side !?? please help....

Sounds like it is flooding, float level wrong, or more likely the needle valve jammed with dirt. Strange it should happen to two sets of carbs, unless they are both old and rubbished.

Pull the bottom covers off the carbs, probably held with four screws. Check out the tiny needle and valve you will find hooked into each brass float. There will probably be a pin you can slide out to remove the float. You'll find it has dirt of some description in there, or if it is rubberised tip it may be rotted. You'll need to replace it, or certainly clean the ones in there. A good blow through will get the muck out, and a wash with petrol.

You'll also need a manual to get the float height settings, which will also explain how to set them.

What bike is it?

[james_j]

Make sure there are no air leaks anywhere, like in the carb rubbers or even the crankcase.