Yamaha V-Star 1100 carburetor experts! Backfiring on low speed decel Idle speed changes as bike warms Cobras?

Question

I just purchased an 03 1100 w/ 10,000 miles. It has Cobra pipes w/o baffles. kjc intake. The carb was supposed to have been rejetted but cannot confirm w/o removal. Bike is getting good mileage and runs fine at hwy speeds but backfires a lot at lower speeds. The idle speed varies from warm to cold. Suggestions? Good carb mechanic in So Cal?

Answer 1

Don't worry about it.  Straight pipes will always pop on deceleration no matter what anyone does to the carb.  Idle will always vary with temp on a carbureted bike.  As long as you are around 1300 rpms when hot you are ok.

Answer 2

Without running it on a dyno, you can't tell if it's running lean or not.

You can pull the spark plugs and see if the are white, black or brown in color.

Brown is the color you want.

Answer 3

Just wanted to agree with shortbus_bully.

All sounds perfectly normal to me.

Opening up the air flow on a big twin is going to bring in a lot of mixture fluctuation, especially at low revs.

By rights it shouldn't even idle until it warms up.