Has anyone ever installed a wiseco piston kit on their F4i? If so, could you tell any difference?

I just bought my F4i and haven't rode it yet. It is in the shop getting new tires, oil change and a few other things done. The previous owner said it was rebuilt with a wiseco piston kit..not sure if it's a bore kit or not...but I am curious about it. Anyone have experience with either of these?

 

I doubt its a bore kit, maybe just higher compression or more durability if it was used for a track/race application.

 

That is what i was thinking, but wasn't sure. I don't know as much when it comes to buildig/rebuilding engines.

 

Do a compression test if you want to see if he changed the compression ratio.

 

What all is there to be gained from a kit like that if it does change the compression?

 

a couple extra hp once its tuned properly and is getting the right amount of air and fuel

 

More compression = more cylinder pressure. More cylinder pressure = more power. Could also mean you need something more then 87 octane.
This is assuming its changed. It could be a stock compression replacement set.

 

+1 Yeah thats actually an important thing to know. If it is a high compression set of pistons you might need to use a higher octane otherwise theres the possibility of predetonation and youll get engine knock. Ask the previous owner if you still can or do a compression test as suggested. Or just wait till you get the bike back and run it on 87 octane. If you get a knock then fill it with a higher octane next time, if not you probably just have yourself a stronger/better set of pistons that keep the stock or close to stock compression.

 

Thanks! I wasn't for sure if there would be any gain or not. I have no way to get in touch with the previous owner, but I am thinking it is either a piston kit that is either stock or close to stock compression. Either way I go I am running higher octane in it. I'm going by the shop where I have it at right now and will talk to them about it. Thanks everyone!

 

Dont bother, you want to run as low an octane as recommended/possible which i believe is 87 for the f4i. You wont get any benefits from running a higher octane if you dont need it, its just a waste of money and It could cause/increase carbon build up in your engine. Stick to 87-89 unless youre getting engine knock, etc like i said before, then go up a grade.