Too rich?

Hi,

I'm taking a wild guess here but I think my mixture may be way too high, spark is black and it'll only run smoothly without the air filter, also when I give it some throttle from idle the revs drop instead of increase. Could these all be related to a too high mixture?

Correct, by the sounds of it.

What bike is it? If you can find a workshop manual, it will tell you what the standard settings are for the carb and you can check what your one is set to. Someone could have adjusted the idle mixture screw or raised the jet needle or increased the jet size

Hi

It's a Chinese 50cc, more of a toy really. I doubt there's much in the way of a manual out there for it. I do know that it has a PZ19 carb, anyone know what setting the jet needle should be at for sea level in the uk?

Here's one for pz carbs. Might be of some help. http://www.ccwthariders.com/uploads/9/7/7/9/9779070/pz_carb_tuning_manual.pdf

You would probably need the workshop manual for your model bike to get the exact setting

That's awesome thanks

You can ever be too rich or too thin.