Yamaha TRX850 Enthusiasts Forum

hi guys just looking for a bit help on what gearing I should be after (size of sprockets)not for top speed but low down grunt out of corners while still having a mid range thanks yoshi

I found by running a 41 tooth rear, it gives me the option of having a slightly lower gearing and I ulternate between a 16 or 17 tooth front sprocket to give me the best of both worlds.
Front sprockets are cheap and it only takes 5 minutes to swap around.
Type in gear commander on the search and go to the link supplied and it gives you all the info you need.
You can type in the std gearing , your current gearing and a custom gearing to give you an comparision in speed and rpm in each gear of the 3 options.
Example
Std 17 - 39
Current. 17 - 41
Custom. 16 - 41

Has anyone gone down to a 15 front and a larger rear sprocket? I am converting to an r6 5sl rear wheel and a 520 pitch chain struggling to find a 41 but loads of 44 45 46 etc

it may have been the JT site, which has all the sprocket dimensions on it.
Took me a couple of hrs of shuffling through to find what I wanted in a 41/520 rear for TRx wheel.
Ended up with an XR500 sprocket 41 in a 520 and just had to drill the sprocket bolt holes out.

I think they have a 520 conversion chart for the R6 too.
Found it..
http://www.jtsprockets.com/catalogue/model/2490

http://www.jtsprockets.com/catalogue#search-results

very helpful ta yoshi

Hi guys! First post so hope your still there...like it says! Trx newbie so my question is...will the speedo be out if I change the gearing of the sprockets?

no, the speedo runs off a drive on the left of the front wheel

But will if you change to a proper front wheel....

Thanks for that

So in that case if I ever changed the front wheel would I have to go with whatever speedo drive from the bike it came of and adjust the wiring?

Trxnewbie wrote:Thanks for that

So in that case if I ever changed the front wheel would I have to go with whatever speedo drive from the bike it came of and adjust the wiring?

Nah don´t bother!

bit of advise on this needed too. Currently have a 16t front and a 44t on the rear (wheel is an rsv and sprocket came with it), as rear is brand new just looking to save a few pennies. With this combination what would i likely end up with, a wheelie machine or a high top speed? dont really want either , just rideable would be good

cheers

16/44 gearing is really low for the trx. You would be lucky to see any more than 170/180 red line in top gear. Would have great pull down low but still won't be a bad wheelie machine. Its still not a 1000cc. I tried 16/42 on track, and was maybe a bit low for that particular track, but on the road would be great. And stops you from doing silly speeds on the road. Run with it you might like it.

Yep 16 / 44 is WAAAAY to low to be of much use, 16 or 17 / 42 is the best compromise gearing.

If you go for a wider rear wheel, the smaller the front sprocket, the more pressure is put upon the chain both side to side and bending to a tighter angle, this of course then leads to changing the chain more often. It has been covered back in the mists of time, try a search. I ran 17/41 for your info.

Dave E

Use the online gear commander, this gives you a good insight to find what you may need to find that happy medium.

1 reason I too chose 17/16 - 41.