Sprocket worth changing?
 

Picked up my new '05 999 mono a couple of weeks ago and unfortunately I now can't ride it for the next few weeks. Booked the first service for the middle of April thinking that with work/weather and other committments it would take me about 6 weeks to get the mileage up on it. Untypical weather and Easter resulted in the bike sitting with 800 miles on it and me pleading with the dealer to bring the service forward. They have done but only to the end of next week.

The bike is from Pro Twins, and I am getting the hugger fitted, the hugger ordered at the same time as the bike but the bike came through two weeks before the hugger did, and the Pro Twins throttle modification done at the first service.

I have been running the bike in to the letter and spirit of the rules...it has not been over 6000 rpm yet..and the first service only extends that to 7000 rpm for another 600 miles..DOH. However my feeling so far is that the gearing of the 2005 999 is rather high.

So to get to the point...at last I hear you all cry...is it a common and/or recommended modification on 999's to perhaps change the front sprocket to one tooth smaller or the rear to go up a couple of teeth? I don't want to make any major change, but the feeling is that first is reasonably high still and I have had to slip the clutch around town more than is perhaps ideal.

It could be that the engine is still losening up and things will improve with mileage...but what are the thoughts on a sprocket change..worth it? If so I might mention it to the dealer and get the change done at the same time as the first service if they can fit it in.

most people slap a 14T sprocket on.

nice icon.............................




oh yes and 1 down at the front is definitely worth doing , 1 up at the back at the same time works even better :sing:

this is worth a look


follow ye olde link.....

I decided against a 14T front. To quote the great Shazaam!

I settled on 15/40 in the end which seems about purfec to me. Much easier round town and pulling away without over reving down the motorway.

(of course you will have to take care accelerating out of tight corners)

:lol:

Poor basteward!

mate .. hope all will be well ... good to see you back on the site ....

I have just put a 14t on the front worth 3 on the back i understand.The effect is good much sharper on take off and easier to ride slow.I would say it was the best performance mod i have made and only cost £22.
Hope this helps

Gone up 2 on rear as 749 is already 14 on front, Makes town riding easier, plus far more pull right through gears with very little change to top end.
Don't know if you need it on a 999 though.

did your std chain still fit or did you need a new one with the bigger rear sprocket?

Used same chain 525 i think, shortend wheel base by about 1 inch approx?.

Thanks for the info. From what you are saying, it will be worth discussing a 14 tooth front sprocket with the dealer when it is getting its first service. Could be that they will be too busy to change the sprocket as well as everything else at the service...but shall see.

too busy to change a sprocket ... ffs ... just tell them to get on with it .. YOU are the customer ... otherwise take it somewhere you'll get some service in future ...

Im gonna be doing the same, just for clarification and cause im particularly thick, would you advise on a lower (14) front sprocket or higher (+2) rear?

Shazaam's recommendation is to go higher on the rear.

Me being a naughty little boy I've done both - 14 tooth front and a 39 tooth rear.

I can't wait to get it back :D

It's not the change from 15 to 14-tooth that concerns me most. I'm cautioning that when you combine it with a change from a 525 to a 520 chain on the liter bikes that you're increasing the chance of a chain failure.

Having a 14-tooth sprocket and a range of rear sprockets and a couple chain lengths in your track toolbox will give you more flexibility in gear selection.

Doh!

Here I was painting myself as the bad boy and you've come and destroyed everything ....

FWIW I have stayed with a 525 chain running 14/39.

Just picked up a 41 renthal rear sprocket for the bike, unfortunately P&H dont have time to fit it (2 week wait) so Im gonna have to wait :flame:

Once its actually fitted Ill tell you how it goes (its a 749 but I can imagine its the same kinda acceleration/gearing variances that would be found on the 999)