I'm swapping out the stock 16 and 40 tooth sprockets on my 05 F4i for a 15 and 44 tooth combination. With stock gearing the top end of 2nd gear is 90 mph! With a six speed gear box I DO NOT need to do 90 in 2nd! I figure the new gearing ought to bring the power band down to a bit more practical speeds. Anyone else have any tales to tell about changing your gearing on an F4i?

Boo

 

I'm pretty sure the stock gearing is 16-46. And 2nd gear should run out about 95-100mph (at the rev limiter). If you want to do a different gear setup I'd go -1 and +2 so you would have 15-48. Otherwise you will be loosing gas mileage. But just to let you know there is going to be a noticable difference in the performance side of it. Its going to feel like a completely different bike. Also you might want to look into a speedohealer to correct the speedometer/odometer. I have a -1 front sprocket and my speedo is off about 10mph so with -1 +2 you will be off 15-20mph so if your going 25 your speedo will say 40-45. I hope this helps you out and if you have any more questions post them up and I'll try to help.

-Jesse-

 

The kid who works the parts counter at the local Honda shop is pretty sharp, and when he looked up the gearing we found one stock front sprocket, 16 teeth, but we found a whole variety of rear sprockets, so I counted the teeth. I just re-counted when I read your post and it is 46! I'm going right now to correct my order! The sprocket should not have any effect on the speedo. Why would it?

boo
PS: 90 in 2nd is probably not quite red lined, but I see no point in running up that high when peak HP, I believe, is at 12, 500 revs.

 

gearing wont lose you gas mileage; misinformation there... but gearing will change your power band
turnin20s is about right on with how much it will throw it off

 

Every F4i has a 16 tooth front sprocket. Most F4is have a 46 tooth rear. I believe there might be ones that have a 47 or 48 tooth rear sprocket.

You will loose gas mileage if you gear lower. Your engine spinning faster at the same velocity = more fuel spent.

 

My stock sprockets are 16 and 46. I'm going with 15 and 48. If I cared about gas milage I'd have bought a 250 Rebel I'm hoping the -1 on front and +2 on the rear will bring the power band into a bit more accesible range. As long as I still have a top speed of 125-130 I'm good!

Boo