Hi all, I've read multiple threads on the matter, wondering what you all thing. I'm running stock 15/36 at the moment on my 05 999. As i have a DP ECU it's derestricted and limiter is around 11.5k RPM. I've done 160MPH on the bike and it was not close to limiter. I don't care much for the top speed, but i would love extra torque, and easier slow / traffic riding. Easiest is to switch the sprockets. researching a bit looks like going to a 14/39 might be a good option, as I do not want to get a new chain (not too cheap) as mine is in good order, and 14/39 will only need me to move the wheel about 0.13 of an inch. any best combos you have found? Lastly, does anyone know how the speedo on the 999 calculates the speed? is it based on the wheel revolutions or on the shaft? as if it's not on the wheel revolutions guessing sprocket change will mess up the speedo as well as the odometer? Thanks in advance.
The speedo pickups are on the other side to the sprocket . Changing the sprocket will not affect the speedo . A bigger tyre circumference will though not that you have suggested changing it but just for information .
No, the speed sensor is the small black thingy attached to the back brake caliper bracket and pick up signals from the steel disk bolts. Oh and if you are revving it all the way I wouldnt be surprised if the engine grenades sooner than you expect.
Went to 14/42 on my 749' though that maybe a bit too much for the 999. Have a look here for inspiration. http://www.avantiraceparts.co.uk/page.php?id=13
I went to 15/39 and find it's a useful improvement in low speed driveability, and I'm more likely to use top gear than previously. Otherwise the change is not too drastic...
Just curious, did you manage to keep the stock chain for 15/39? or did you have to buy a whole new longer chain? I'd really like to keep the same chain, as it's in good condition, it's a DID one as well. using http://www.gearingcommander.com/ I've found that i should be able to keep the same one if i go to 14/37 from the stock 15/36 Having to move the wheel only 0.02". I wanted to put in 14/39 but i'm being told i'll have to move the wheel 0.36" forward and i dont think i have that much play room, i dont recon i can just extend the chain can i? Also, read somewhere that you should keep the front / rear sprocket even / not even, if front is even number of teeth, put uneven rear, to keep the wear from being consistent. True? Thanks,
I changed the chain at the same time to be honest - I think it needed three more links. Got chain and sprockets from BikeTorqueRacing and they were very happy to advise... might be worth giving them a call if you're not sure. I've heard about the uneven wear theory but can't say I'm going to worry too much about it! There's also a suggestion that dropping a tooth on the front puts too much strain on the chain, which I'd be more concerned about with the very torquey nature of the Duc engine.
Just got off eBay a Renthal 37 back and steel 14 front. Installed today. Managed to do so without splitting chain. Will report back after acouple rides. Wheel was able to be kept in the same place With the same chain from stock 15/36 to 14/37
went for a good 20 mile run today. other than some rectifier issues I'm currently working on, the bike felt great with the new 14/37 combo! it felt... no better word, then just 'happier'. it dropped the speed just a tiny bit it seems on each gear, but it clutches away easier, it accelerates a bit better, and does not hiccup anymore in lower revs. Interesting, didn't think sprocket change would make such an impact on smoothness of the bike? maybe just that it makes it easier on the engine to pull it along? I don't think i would change it any higher though, would not want to rush through gears just to move.
Hi, I using 15/39 and its much better in the city and also out of the city i can use the 6th gear at 100km/h as well. I using JT sporcket fron tis JTF741 and rear is JTR744.
