Do I need to readjust a carburetor or injection when I change the exhaust?

Question

Accepted Answer

If the old one is broken and you just replace it with an identical part, no. If the silencer or muffler is replaced by a different type, it may be the case that the fuel-air mixture in the intake tract no longer is according to requirements. Then it must be retuned. This is the case when you replace a Quiet Cigar Muffler with an accessory Fishtail, which has less baffles. Or the Fishtail muffler by a SuperTrapp megaphone. Even if you double the number of discs on the SuperTrapp muffler, you may need to retune.
The reason is the flow of the exhaust gases in the exhaust system. The exhaust system thus has an influence on how quickly the cylinder is emptied after the combustion stroke and how much fresh gases can flow in. How much you have to readjust cannot always be predicted in individual cases. However, if the Harley starts worse after the exhaust change and seems slower in terms of acceleration, it must be retuned. Spark plug color reading also helps here.

Exhaust

Have any questions?