I got my F4i used a couple months ago and it already had some mods like slip on, PCIII, ect. Now i have just discovered that the rear sprocket is 48 teeth making that +2. now the front sprocket is still 16 so there is no change there. My question is.. does this effect the speedo/mileage? how has it changed the performance of the bike?Thanks for any help.

 

You will have to wait for the more knowledgeable guys to pop their head in here, but from what I have heard you will have difference in both categories. I think its like a 3:1 ratio rear sprocket:front sprocket. So basically you have almost done the equivalent of dropping a tooth in front.

 

It makes the bike quicker and brings down the top speed. Your speedometer will be showing faster than you are actually going. Also the bike has less miles on it than the odometer shows. I just got a speedohealer hooked up on mine. It corrects the problem so you don't have to geuss on speed. It is a very soild purchase. The top end difference you will never notice. the bike will still probably do 150mph. My bike is -1 in the front and +2 in the back and I really love it. If you go to the speedohealer website it will tell you how far off it is.

 

Hey thanks for the quick responses. It looks like im about -4.2% off. so does that mean i am about 4 MPH slow all the time?

 

NO it means you are always 4.2% off. At 100mph you would be 4.2mph off at 50mph you would only be 2.1mph off. Not that much maybe you don't need to get the speedohealer with my sproket change it was about 17% off so I had to get one instead off do the math. I wouldn't worry about it. Also for every 100 miles it adds 4.2 miles, again not very noticeable.

 

ok, now i have a new issue with all of this... here are my specs. '03 F4i with scorpion slip on, PCIII, +2 in the rear. Now in my opinion this bike should be coming up in the front like no ones business. Unfortunately, i can't get the front wheel to come up to save my life. about the only time it comes up is at redline in 1st gear and only a couple inches. what could be the problem?

 

Its all about how you ride and know your bike. If you want to pop a "wheelie" rev the bike up to around 7 or 8 grand pull in the clutch and the release the clutch and give more throttle. Thats what is called clutching it up. For more information about "poppin wheelies" I recommend you check out the stunters corner.

 

https://cbrforum.com/m_596713/tm.htm

 

Yeah i know i can clutch and bring it up like no other, i was hoping with all mods i could bring it up without having to use the clutch...

 

There is the technique called the powerband way. You get up to around 7 or 8K's, release the throttle, letting the front end dip down for a second then you rip the throttle and the front end will come up. I started doing it the powerband way and I clutch it up, clutching it comes up faster and you have more control. But whatever you feel the most comfortable with doing is what you should practice on. Good luck