Jump to content
Sign in to follow this  

12 tooth sprocket 2001 wr250

Recommended Posts

is this gunna make my bike much slower? and is it going to make a very big difference in acceleration. i know its only one tooth thats why i was wondering.

Share this post


Link to post
Share on other sites

Yes it's going to make you WR a lot slower. I only put a 12T on for super gnarly technical trails like Moab. I like it there.

Share this post


Link to post
Share on other sites

Yeah, it's only one tooth, but it's one tooth on a small sprocket. Expect about an 8% decrease in top end. I tried it and it's too much even in the tight twisties. Try adding two or three teeth on the back instead.

13:52 = 4.00

12:52 = 4.33

If stock is too tall for you, and 12:52 drops too much top end, you want to be somewhere in between, like this:

13:53 = 4.08

13:54 = 4.15

13:55 = 4.23

13:56 = 4.31

I'd try the 53 or 54 tooth rear if it were me. Depends on where you'll be riding.

Share this post


Link to post
Share on other sites

Depending on the bike you may need a longer chain with too large a rear sprocket. A smaller CS might be an inexpensive way to experiment.

.

Share this post


Link to post
Share on other sites
Yeah, it's only one tooth, but it's one tooth on a small sprocket. Expect about an 8% decrease in top end. I tried it and it's too much even in the tight twisties. Try adding two or three teeth on the back instead.

13:52 = 4.00

12:52 = 4.33

If stock is too tall for you, and 12:52 drops too much top end, you want to be somewhere in between, like this:

13:53 = 4.08

13:54 = 4.15

13:55 = 4.23

13:56 = 4.31

I'd try the 53 or 54 tooth rear if it were me. Depends on where you'll be riding.

your saying if stock,,which is 13/52 is too tall go 13/53,4,5.6.,,,isnt that even taller? :excuseme:

Share this post


Link to post
Share on other sites

I just starting running a 12-50 (from 13-50) combo and seems to be working fine. Really like the low end grunt and minimal loss of top end.

Share this post


Link to post
Share on other sites
your saying if stock,,which is 13/52 is too tall go 13/53,4,5.6.,,,isnt that even taller? :excuseme:
Yeah, you're right. Wrong terminology.

Also the poster who mentioned a 12T CS being a cheap way to experiment was exactly right. I tried it out for only $10, and it didn't suit my riding style, area, etc. Some guys do like the 12T CS, but it wasn't for me.

Share this post


Link to post
Share on other sites

Jamipenny:

Here in Idaho we have a combo of Hi-Speed desert 2-track and some slower mountain single track. I have a 2003 WR 250F and I tried the "stock" gears..(13 by 52) Nice in the desert but harder then hell for me in the mountains. Had to hit things harder and faster.........being 58 years old I DIDN"T WANT TO...........

Put a 12 tooth on and found the bike much easier to ride....still able to do 65 + MPH in the desert...............really for $15.00 it is the best money I've spent on my bike............."try it you can always change it back"

Share this post


Link to post
Share on other sites

A 12 counter sprocket is harder on the chain. I do all my gearing changes at the back sprocket.

Share this post


Link to post
Share on other sites
i ride tight sandy trails and i find the bike just cant really lug around enough.

You will gain much insight and knowledge by spending the $10 - $20 and experimenting. All I can say is it worked for me on my bike but I wanted the low speed for the extremely tight steep trails terrain. I may put the original CS back on and get a larger rear sprocket (and possibly a chain if needed) but the smaller CS was an excellent and cheap way for me to 'get a clue'.

edit - And yes I just saw the other persons post a smaller CS is harder on the chain. How much? I don't know but it is still a good way to experiment.

Good luck!

.

Share this post


Link to post
Share on other sites
your saying if stock,,which is 13/52 is too tall go 13/53,4,5.6.,,,isnt that even taller? :excuseme:

I believe "taller" means a wider ratio and higher top speed, so going 13/53,4,5,6 is going lower/shorter (shorter shift ratios) not taller - i.e. making the gear taller (or wider) means being able to ride it longer before having to up shift.

Share this post


Link to post
Share on other sites
A 12 counter sprocket is harder on the chain. I do all my gearing changes at the back sprocket.

Changing 1 tooth on the CS is really changing 1/2 a tooth as far as the pitch is concerned as to how the chain "sees" its rotation through the CS. The 12T CS on my WR has over 1000 miles on it and is still going strong along with the stock chain and stock rear 52T sprocket.

Share this post


Link to post
Share on other sites

av, how do you like the greaing with the lower tooth on the front? did it lower the top speed by much and is there a big difference in acceleration?

Share this post


Link to post
Share on other sites

I'm not av, but my answers - yes I like it for super tight stuff, yes and.....this one's hard. Kind of. You run out of gears a lot faster though and end up shifting a lot more than stock gearing. Can't get lazy with it on and you'll end up trying to shift to "6th" all day long if you encounter any amount of open terrain. Why not just slap one on and try it. Under $10 and you'll know in an hour or so if it suits your style/terrain.

Share this post


Link to post
Share on other sites
av, how do you like the greaing with the lower tooth on the front? did it lower the top speed by much and is there a big difference in acceleration?

For what I ride in the woods, I'm mostly in 2nd and only use 1st gear if it's really tight. However, with the 12T CS, the gap between 2nd & 3rd is MUCH better IMO for woods stuff - the stock 13T CS makes you clutch a bit more using 2nd in the woods, so I like the 12T CS better. Top speed will drop from 85-ish to around 75-ish - like I want to do 75mph in the woods :bonk: I only use 5th gear in the open chasing after the big bore bikes (450s, 525s & 650s). My WR still leaves the YZ250Fs behind after it catches up to the YZ250Fs as they top out around 65mph with their stock gearing.

As for acceleration, my bike has the YZF e-cam so along with the 12T CS, it has a lot more snap than the stock setup - so yes, it accelerates better than stock. BTW, going with a larger rear sprocket will most likely require you to get a longer chain and you may also need a bigger rear chain guard (i.e. the metal guard that goes under the swingarm). If your terrain is not too tight, try the 12/50 combo if you want the ratio to be something right in between the stock 13/52 ratio and the lower 12/52 ratio. As for me, in the tight stuff, I like the 12/52 for the WR a lot. :excuseme:

One more thing to note, using a larger the rear sprocket will result in more of a tendency for it to dig into ruts as you fall into them...

Share this post


Link to post
Share on other sites
I'm not av, but my answers - yes I like it for super tight stuff, yes and.....this one's hard. Kind of. You run out of gears a lot faster though and end up shifting a lot more than stock gearing. Can't get lazy with it on and you'll end up trying to shift to "6th" all day long if you encounter any amount of open terrain. Why not just slap one on and try it. Under $10 and you'll know in an hour or so if it suits your style/terrain.

Nobody asked you... :excuseme: j/k

Share this post


Link to post
Share on other sites

thanks for all your replies. Who needs to go 140km an hour on single tracks. i only need to do 100km and hour. thanks for all the help. my sprocket will be on by monday i will let you know how i like the set up.

Share this post


Link to post
Share on other sites
Nobody asked you... :p j/k

Hey AV, :excuseme::bonk:

:busted:

Were we talking about gearing? :bonk: I think I'll eventually end up with 13/54 as the 12/52 combo is too short for the more open stuff around here (west). My WR is a rare plated CA model and I end up hitting the highway sometimes too and 12/52 is just painful there. Wish Yamaha had done what Kawi did and made a closer ratio'd 6 speed. Oh well.... :p

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×