After messing with my brothers F4i exhaust and my F4 exhaust I realized you can't use an F4i slip on. But what if you were to get a stock F4i header and put it on an F4 would the only problem be with the exhaust bracket hanger?

 

On the F4 - you can put an F4 slip on, or an F4 system, or an F4i system. You can not put a F4i slip on, unless you also install the F4i header.

The F4 and F4i systems are the same overall - but - have different components to make up that shape. You can't mix and match - you have to go all one way, or the other. A square peg in a round hole type thing.

Anyhow - if you have an F4i header on your F4 - then you can install your friends F4i slip on. That'd work. I could see that as a cheap option if you had the pieces from a friend, or got lucky in a junk yard/local bike forum.

 

The exit angle on the f4i header is different thanthat of anF4. As long as you have the appropriate header for slipon your putting on it will work.