Simple gearing/wheel size question

[JatKat]

Theres probably a simple answer to this, but Ive thought about it too much and confused myself!

If I have standard gearing on my 1100 Katana (42/15 I think?) but am using a 17inch rear wheel from a GSXR, will my gearing ratio be changed? Im thinking that Id get better acceleration and less top end?

Anyone? :?

[Pete Logan]

Smaller rolling radius on the rear gives lower final gearing, so yes, you would expect quicker acceleration and a loss of top speed. Your speedo will also read fast.

To get an idea how much, if you run the difference in circumferences of the two tires as a percentage of the larger, you should get the same percentage drop in top speed.

Pete

[Mario Padilla]

Speed Change?

I believe the speedo is driven by the front wheel so if you haven't changed the front wheel your speedo will be unaffected.
MP

[Pete Logan]

You're right

I was thinking of the wrong bike. Ooops

Pete

[JatKat]

Thanks for the info guys.

Im doing the 530 chain/sprocket conversion and wanted to make sure I get the right size sprockets. Its got one tooth extra on the front sprocket at the moment which probably brings it back closer to the stock rolling radius overall with the smaller wheel.

Cheers

James