Hey All,
I have a 1980 x-1/9 with a 1.5 ltr and a 2 bbl carb it satrts and runs when it is cool but after it gets up to temp it stalls out whenever the clutch is disengauged. It does start right back up if I pop the clutch or after I turn the key and it runs till the next time I have to slow or stop. any Ideas where to start?

could be your idle set too low, or if it has suddenly started to do it, your idle jet is blocked.

To check the warm idle speed you just need to tweak the screw that acts as the stop for the throttle arm on the carburettor. It should only take a small adjustment. On the euro spec carbs you tighten the screw but on the federal spec carbs I have no idea other than to assume the same. Just make sure that the result is to push the throttle arm towards the open position a little.

If this makes no difference then you will need to clean the jets on the carb. Only remove one at a time to avoid mixing them up, give it a good blow through with air and possibly with a thin pipe cleaner. Refit the jet and move onto the next one.

The alternative is to try and rely on a can of carb cleaner but if it is a proper blockage this won't have much effect...

Thanks guys
I pulled the jets and gave them a good cleaning and I tinkered with the idle screw until I had good RPMs.. since i had it open I changed the plugs cap and rotor gave it a new airfilter fixed a few old hoses and vacuum lines. some where in the Mix I fixed the issue. every thing seems to be running better. still needs somee tweaking but I can't complain for a 30 year old car with only 28,883.6 miles on it!
thanks again!