Hi I need your advise, I am looking at a set of Spockets for my CBR on E Bay and I can seem to find the Standard sizes for the CBR 1000 F in my Workshop manual. The ones on E Bay are 15 teeth for the front and 42 teeth for the rear do you think this would be Standard. Thanks Wazza

 

I know the rear sprocket is 42, but I believe the front is 17.

 

Hi if the front sprocket is smaller it should give me more top end is that right ??

 

The '87 & '88's have a sprocket ratio of 17:43
'90 and up has 17:42

By droping the front you will get less top end and more off the line.
For each tooth you drop up front is about the same as adding three to the rear, or in your case dropping two to equal adding six at the rear. At highway speed in top gear you should see a big increase in RPM (somewhere around 668 RPM)

 

What the others say are correct. 90 and up were 17/42 stock. I have gone -1 (taller gearing) in the front down to 16 and +3 (shorter) in the rear, now having 16/45. I can't remember what the gear ratio is at this change, but it is significantly higher from what I thought stock was like 1.7 or 1.8 something. This has helped out enourmously but there is the sacrifice of increasing rpms and loosing top end speed. I'm not really worried about top end, as I know it will still go above 150 taking into consideration for the 5-12% error (up to 8 with stock, .5% per tooth change). I'm not worried about top speed as my goal was to broaden the girth of the powerband in more smoother gears like 3rd and 4th and 5th. Especially for agressive cornering.