K&N Air Filter = Carbon Build-up?

A friend of mine called me tonight asking me if I'd ever heard of K&N air filters causing excess carbon build up. He has a Katana that he's done the regular mods to (full exhaust, jet kit, timing advancer, etc.) and a "katana" specialist told him that the K&N would cause excessive carbon build-up in the motor.

I told him that I'd never heard of anything like that but that I ran stock filters in my bikes...but I didn't see how having extra airflow could cause any problems as long as he had the bike tuned for it. Which I know he's had it tuned properly b/c of who he's taken it to for work.

So, what says the all knowing BBS?

Thanks!

Cliff

 

On some fuel injected applications an over oiled K&N will coat the mass air sensor with oil and cause some erratic running. Maybe the mechanic is referring to K&N oil be ingested into the motor?That aside, K&Ns pass too much dirt, you'd be much better off with a foam element like pipercross offers. Besides, there's not much to be gained with replacement filters on modern sport bikes anyway.

 

Huffdaddy tuned it for him and he's pretty meticulous about his bikes so I doubt he'd be running bad gas. This is just what a few other "kat specialists" have told him and now he's a little concerned.

I told him I wouldn't worry about it too much, that even if it did lead to increased carbon build-up that I was sure it'd be a pretty negligible amount. I mean, people run K&N's in cars for 100's of thousands of miles without many problems that I've heard of.

 

Thats what I told him, I said see what Charlie thinks, but I don't see it as that big of a deal.