right cylinder popping

[pfo186]

hello all,
finally got the bike running pretty good (77') but when i let off the gas, and when the bike is first fired up, the right side cylinder pops/backfires and the exhaust pipe becomes slightly discolored (purplish blue color) while the other cylinder runs good and the pipe doesn't get discolored. is the ignition timing off on the right side causing it to run hotter? can this damage the motor running it like this cause it runs fine and only does it when i'm slowing down at lower speeds. everything is stock on this bike, so jetting shouldn't be an issue. any input would be appreciated.

thanks

 

[OliverB]

Sounds more like some sort of air leak on that side leaning out the mix.

 

[HoughMade]

Yep, for some reason, it's lean. Yes, running lean and hot can cause damage. It will burn out an exhaust valve at some point if it continues.

 

[pfo186]

alright, thanks guys