K & N and rejetting

Hey Guys.
I just finished my upgrade to blade fuses and the job looks surprisingly good.
Anyway, i was wondering if any of you have purchased the K&N air filter and if you've really had to rejet. Chacal's comments says you do, but I wanted to know if any of you have. Thanks!

 

I did. Went up one jet size. Main reason is that after a year of riding I developed an oil leak at the head gasket. Turned out the head was warped. Now I can't verify that this was caused by the K&N lean out the mix and running the engine hot. But I decided not to take any chances after putting so much into the head.

 

The answer is maybe -- depends on if you have an aftermarket exhaust especially.

Our bikes came from the factory running slightly lean. Thus, almost anything you do to it will lean it out further. So although you might be able to get away with the performance air filter for now without jetting, you'll probably need to fix those jets in the future anyway - so either do it now or at least plan on it.

I've got both the K&N air filter, and a MAC 4-into-1 exhaust on my bike, and jetted up to the Stage 1 kit -- made a world of difference

 

I have owned 2 Seca 650s and found both to be lean from the factory, it was the start of the EPA influance on motorcycles. Adding a K&N filter or anything else that allows more air flow would only compound this lean effect. The atached article does a good job of adressing this. I have read several others that stated the same. I geted mine up two sizes on the main with a K&N and found it to work well. But!!!!!! carbs are funny animals and thats why its called the art of carb tunning. Your bike may be differant as the privious poster stated though its safer rich than lean.

 

lhttp://www.totalmotorcycle.com/pdf/sav ... ndards.pdf

I was not able to atach the file but the address is above.

 

http://www.totalmotorcycle.com/pdf/savi ... ndards.pdf
well I swear its in there lets try again.