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Sprockets 'n Stuff

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by hornet, Apr 15, 2009.

  1. I know I've asked something like this before, but I've searched and can't find it.....

    The Hornet has a 42 tooth rear sprocket; I've counted 'em.

    I have had come to hand a 43 tooth rear sprocket.

    So, if I was to fit the 43 tooth sprocket, what difference will it make to riding the bike, and what (if any) difference will it make to my speedo (bearing in mind the speedo is run by a spur gear directly off the countershaft?)


     
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  2. It'll make balls-all difference, a single tooth on the rear is a negligible addition off the racetrack.
     
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  3. And your speedo will be further out (optimistic)
     
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  4. So, not worth doing? Cool. As always, ask the Netrider experts!
     
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  5. Whoa there - if you've got it, go ahead and use it, it'll make virtually no difference to either the feel of your bike or your speedo - you'll be downgearing it by what is technically known as a "poofteenth." Ride through one radar speed checker to make sure you know exactly how far out your speedo is - I'd do this anyway, even on stock gearing, they're always out unless they're Beemers. So just have a quick look to put your mind at ease and go for it.
     
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  6. So, it will make it exactly one poofteenth easier to wheelie, and it will over-read on your speedo by the same poofteenth.
     
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  7. Both my Beemers have been noticeably optimistic, although a bit of fiddling with the electronic one on the K could have calibrated it, had I ever bothered.
     
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  8. It WOULD be nice if the bike was running at, say 6,000 rpm at 100 kph, instead of the 5,000 it is now. But I guess you'd need at least two more teeth on the rear for that to happen....
     
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  10. Right now, at 100kmh, you should be doing exactly 5112rpm. If you go to the 43 toother, you'll end up with an earth-shattering 5234rpm at the same speed. That's a whole 2.3% difference, and that's roughly the amount you can expect your speedo to move by. Bear in mind that it's almost definately not correct now.

    Just throw it on, I don't reckon you'll notice a thing.
     
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  11. Thanks for the good advice, folks :).
     
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  12. If you want to be at 6,000 at 100kph you'll need about a 47 tooth rear. Or just change down a gear, its much easier and cheaper.
     
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  13. If you do ever want to play with sprockets and you want to support an Australian company, Chaingang were great to me with the SV. Good prices (a long way more than e-bay). They'll make a sprocket for you to order and ship overnight.
     
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  14. It was reported 6 or 8 weeks ago that Chaingang were out of business. Bloody bad news that. Have they restarted?
     
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  15. Damn, I missed that. Another good supplier gone out of business eh?
     
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