12-43 to 13-46? + Chain..

Been trying to find this info but am coming up short so I'll try to keep it brief.

A. Is 13-46 going to be the same as 12-43 as far as gearing?
B. I'm assuming I need to get a new chain.. Any recommendations for the lowest friction?

I'd do a kit too if that made it easier.. The 12-43 is a loud bastard and I feel my chain is wearing faster..

Thanks so much in advance!

You'll need a 110L chain to run 13/46 sprockets. 112L could work too if you're going to run a MT43 since its significantly taller than stock and even the D606.

I've had good luck with RK X-ring chains.

Make sure your chain slider is still in good shape, they tend to get worn through quickly as the chain gets old and kinky.

awesome, thank for the valuable info..

In the rear, I've been running Pirelli Rallycross which seem pretty tall as well.. I've got some Michelin T63's which seem more like stock but after those, I'm going back to the Rallycross tires as I love their street performance : )

is "RK X-Ring" a brand or type of linkage? Sorry for the noobish questions but I've never upgraded a chain/sprocket before..


Much love..

RK is a brand, X refers to the type/style of O-rings used. See here for sprocket ratios:

http://www.jtsprockets.com/fileadmin/files/jtgearratio.pdf

Sarah

According to this: http://gearingcommander.com/

12-43 is pretty close to 13-46. You can play around with the figures and wheel sizes on that site specifically for the WR250R or X.

Also check out this post, awesome table:
http://www.advrider.com/forums/showpost.php?p=8568611&postcount=1483

>"The 12-43 is a loud bastard and I feel my chain is wearing faster.. "

True. Small countershaft sprockets wear chain faster. Go with 13 or 14 countershaft.

Wow, thank you guys all for your responses. This has been very helpful.. I was thinking13-46 to match the 12-43 but now I'm thinking 13-48 as it doesn't seem I'd loose too much top end for hwy driving.. Very cool, much love!

would 112 links be enough for 13-48 on D606 height tires?

I just put on a 14 -49 with 112 link o-ring chain. Seems to work real nice. I hope this helps keep the chain off the slider and swing arm as well. This gearing looks to be close to stock with a D606 on there.

I got 13t as well for the front as well. I will pop it on when I want to do some rough off road.

bsheet2,

How much "gap" was left between your rear D606 and the swingarm (i.e., with your 14/49 set up)? Do you think a 50 tooth rear sprocket would work with that set up? Or would it contact the mudflap? Thanks for your help.

I do not have a D606 on the bike yet. My comment in the above post is from using the gear commander web page. It calculates speed and RPM for different tire sizes as well as sprockets.

Gearing Commander shows the sprockets will be 1/10 th inch further appart with 14-49 combo. So a D606 should nbe just fine.

With 14-50 combo it shows the gears will be 0.08 inch closer together than stock. This would move the tire o.08 inch closer to the mud flap. If you have a D606 on there now, you could make a judgement if this would be ok.

The above all assumes a 112 link chain.

Right now I have a 120/80 MT21 raer tire on the bike. It is not as tall as a D606. So I can't give you any sort of judgement. The lower profile rear tire also results in a gear ration that is slightly lower than stock. I give up about 4 mph on the top end. This feels pretty good. The D606 and the 14-49 sprockets shows to be about 2 mph slower than stock.

Sorry if my above post was missleading.

Here is Gearing Commander. http://www.gearingcommander.com/

Thanks for the info. Took a look at my current set-up. If it's only 0.08 inch's closer, I think it will work! I'll post a reply when I receive the parts and get them installed.

Just remember. If your current chain has many miles on it, the chain will have some stretch in it. So a new cahin will cause the tire to be a bit closer to the mud flap. If you have an idea of how much adjustment you have done since the chain was new, this will help you judge.