Back firing

[kerschey]

Any ideas why my bike sounds like crap when it runs and back fires out the exhaust pipe. I changed the oil and found gas in the oil adjusted the carbs for k&n filters, and replaced the fule cock.

[scottynoface]

You're running lean. If you have the stock exhaust and K&N filters you're bringing a ton of air in but can't push any more out.

[kerschey]

You're running lean. If you have the stock exhaust and K&N filters you're bringing a ton of air in but can't push any more out.

So i should look into getting new eshaust?

[Enjay386]

Mine backfires once or twice at the beginning of the season but other than that no problems...

[JAVELIN350]

mine does to when it's still cold

[scottynoface]

Is it a backfire or an afterfire?

[kerschey]

it does it when you rev it up and let off the gas

[Katana1100]

sounds lean to me too. you said you set carbs for k&n's but did you re-jet? Try this guide, it it may help.

http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html

[kerschey]

It was already rejeted but the person put the washers on the wrong side of the needles so i had to fix that! (they had the washers on top of the clips instead of below the clip

[Katana1100]

It was already rejeted but the person put the washers on the wrong side of the needles so i had to fix that! (they had the washers on top of the clips instead of below the clip

Duh go figgure.did that help?

[katcan]

take carbs apart blow out pilot jets with compressed air. While jets are out blow out passage way as well with compressed air. Spring time problems usually occur because bikes were not put away properly. Drain carbs in the winter and use stabalizer just in case. Should eliminate carbs from getting bunged up.