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Discussion Starter #1
so, if im replacing my rear wheel and drive gear(to a larger sprocket)... should i also replace my driven?

im jumping from a 36t to a 45, and changing my chain too of course.
 

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it's always recommended to change the pair at the same time... that's the conventional wisdom. that said, if the front sprocket is in good shape and showing no sign of wear you could just do the rear. considerations are things like, how much is the new front sprocket... if it's $15 and you're not sure if it's in fine shape then it might be a good investment to go along with your $100 chain and $80 rear (i'm making up prices to illustrate the point) or if your rear is showing slight wear but it's aluminum and your front sprocket is steel, then again, you might just get the rear. unless the front is reeeeeally pooched the only real issue is how much faster you'll wear out the other components. you pay now or you pay later! you can only defer maintenance, you can never avoid it!
 

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that's a massive jump in tooth count. What the heck would you large for? If you don't raise the tooth count up front you'll end up with a quick blast 0-30mph or so then nothing......
Again...why such a massive difference?
 

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You're gonna want to get a more suitable rear sprocket amigo.......seriously.
 

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Discussion Starter #7
the chain isnt the same, had to buy a new one and take a few links out.

i dont know where to find a smaller sprocket for a kawa wheel from the seventies before i go to work tomorrow... so i'll have to ride this set up til atleast the weekend.


whats the main problem with a sprocket that size? my kawasaki kz 400 has the same rear wheel set up...
 

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You won't need to use first gear.

Guessing that the (honda) gearbox sprocket is around 16 teeth, the 36T rear sprocket gives a 2.25:1 ratio. The 45T rear gives a 2.81:1 ratio, or about 20% different. That means that your rear wheel will go around 20% slower with the 45T rear sprocket. So, first gear will become irrelevant, and top gear will be winding out 20% sooner (at somewhere around 70 mph). Good scrambles set up.

I'm guessing that the KZ400 comes with a much larger gearbox sprocket.
 

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A 20T gearbox sprocket would you give the same ratio... if it will physically fit in the space at the gearbox, and if your present gearbox sprocket is indeed 16T.
 
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