der motoren bauer aus usa sagt
Hi, here are 3 things to check on your engine.

1. make sure you do not have any vacuum leaks, this will cause the headers
to turn red, idel the engine down to 1000 rpm, if it runs smooth and does
not surge, you do not have a vacuum leak.
2. check timing at 1000 rpm it should be 12 degree, and at 3000rpm it should
be 32-33 degree.
3. the last thing that will cause your problem is the carb jetting, if the
carb is running lean (to small of jets) this will cause the problem.
Please let us know what you find out.