Hi,

I've got a set of brand new after market 1999 CBR600 FX/FY exhaust headers - my question is will they work ok (in engine/fuelling performance terms) on a 2001 CBR600 F4i? (my F4i headers have a big hole in them and the 99 headers are available at a great price).

The reason I ask is that the 99 is carbureted and the 2001 is fuel injected - the 99 down-pipes are shaped differently from the 2001 bike - the number two pipe on the 99 headers has a specific and noticeable bend in it that the 2001 bike doesn't have - so although the bikes share a lot of parts the differences in fuel delivery methods (carb v injection) has resulted in slightly different header pipe profiles (they also have different part numbers) - I have no deep knowledge of fuelling and exhaust systems - but I'm assuming that different spec headers from a 99 carb CBR will not work properly on an F4i CBR (without a remap) - because slight differences in the shape and length of exhaust pipes are there for a reason.

(I've done some research and understand that 99 headers will physically fit the 2001 bike if you carry over a 99 spec can/link pipe as well - my main concern are performance issues resulting from the swap).

Thanks for any advice.

 

Hi guys - I picked up some decent OEM F4i headers from a breakers - so won't be fitting the FX headers - no need for further discussion unless the topic interests you.