650L 15/48 combo anyone?

Search results show lots of 13/48/50, 14/48/50 etc combos but didn't really see anything regarding leaving the 15 oem and just increasing the rear to a 48 or 50. I know it'd be easier to just change out the c/s sprocket but am pretty concerned about all the posts that mention eating away at the countershaft due to the hardened steel that is used to make the sprockets. I'd rather just change the rear sprocket than to gamble on having to install a shaft at the engine end due to excessive wear. Not concerned with having to ever exceed 60~ mph, just don't care for the 2nd gear in the trails feeling too high.

48 or 50? any recommendations out there? 50 too large in dia to fit without rubbing the C/S sprocket cover (oem). Chain guard is already removed.

i would say go with a 48 rear THEN if you are taking the bike out on a off road only trip for a weekend or something you can also buy a 14f and put that on. 48 rear gives you some good choices for street and dirt gearing with just having to switch a front from 15 to 14 if you want to. I tried to see if a 47 that i had off my Yami would fit this weekend but its a bit off on the bolt pattern, so off to ebay it goes.

Search results show lots of 13/48/50, 14/48/50 etc combos but didn't really see anything regarding leaving the 15 oem and just increasing the rear to a 48 or 50. I know it'd be easier to just change out the c/s sprocket but am pretty concerned about all the posts that mention eating away at the countershaft due to the hardened steel that is used to make the sprockets. I'd rather just change the rear sprocket than to gamble on having to install a shaft at the engine end due to excessive wear. Not concerned with having to ever exceed 60~ mph, just don't care for the 2nd gear in the trails feeling too high.

48 or 50? any recommendations out there? 50 too large in dia to fit without rubbing the C/S sprocket cover (oem). Chain guard is already removed.

I was concerned with the c/s wear also. So i chose to go with 15/48. Very happy with it. Can cruise at 70 no prob. Way better offroad too.

Like DENN says, run 15/48 and keep a 14 with you to swap out at the trail head.

I don't think that there is much to worry about with a 14 sprocket. That's what the XR600's have. The main thing is the extra motion in the chain links wrapping around the smaller sprocket. It is very minor. My last set of chain and sprockets lasted 4 or 5 years of riding most every weekend.

Even at 14/50 the bike will still go about 75 before the rev limiter kicks in.

The problems appear to start with a 13 sprocket.

I don't think that there is much to worry about with a 14 sprocket. That's what the XR600's have. The main thing is the extra motion in the chain links wrapping around the smaller sprocket. It is very minor. My last set of chain and sprockets lasted 4 or 5 years of riding most every weekend.

Even at 14/50 the bike will still go about 75 before the rev limiter kicks in.

The problems appear to start with a 13 sprocket.

Was it you or Dave that posted awhile back about what each gearing combo equals to in final drive ratio?

I know it'd be easier to just change out the c/s sprocket but am pretty concerned about all the posts that mention eating away at the countershaft due to the hardened steel that is used to make the sprockets. I'd rather just change the rear sprocket than to gamble on having to install a shaft at the engine end due to excessive wear.

Isn't it the chain and sprocket that take the beating? Why would the shaft wear? I was planning on the 14T in front. Is it really that big of a concern?

Was it you or Dave that posted awhile back about what each gearing combo equals to in final drive ratio?

It's a simple as just doing the division. Multiply in the trans and primary reduction ratio to get an overall reduction.

15-45 = 3.00

15-48 = 3.20

15-50 = 3.33

14-48 = 3.42

14-50 = 3.57

I hit 4000 posts on a math related topic. How connected. I guess that I need to get a life...

You are gaining on me quick Martinfan. At the rate you are going you will be passing me in no time. How do you post so much? Don't you work?

Isn't it the chain and sprocket that take the beating? Why would the shaft wear? I was planning on the 14T in front. Is it really that big of a concern?

Shaft wear is a problem. I think it is more related to the quality of the sprocket than the number of teeth though. As far as wear goes I would guess that it is a product of the torque delivered and the number of times the shaft turns.

It's a simple as just doing the division. Multiply in the trans and primary reduction ratio to get an overall reduction.

15-45 = 3.00

15-48 = 3.20

15-50 = 3.33

14-48 = 3.42

14-50 = 3.57

I hit 4000 posts on a math related topic. How connected. I guess that I need to get a life...

You are gaining on me quick Martinfan. At the rate you are going you will be passing me in no time. How do you post so much? Don't you work?

Ya, I know the math... I just didnt want to do it and map it out like you have. Thank you CL! Its much easier to post a link. Wow, I'm becoming a real bum!LOL.

4K, congrats. :applause:

I do work, as Toyota tech... That is the problem. Along with a suffering economy. I will "work" maybe 2-3 hours of the day that I am there for 8. No broken Yota's, if there are no one wants to spend money to fix them.

I spend time in TTT, xr650/600, vintage, DS, moderator, help out a bit in the smaller Honda forums. Just gets boring at "work" with no work!:)

Shaft wear is a problem. I think it is more related to the quality of the sprocket than the number of teeth though. As far as wear goes I would guess that it is a product of the torque delivered and the number of times the shaft turns.

So In my mess of a mind, I would think a softer steel sprocket rather than a harder A/C grade aluminum sprocket would be better on c/s wear. The softer metal would give and take the abuse over the hardened c/shaft. A designed in weak point.

I am no engineer though. I just work with what they designed! LOL

So does it wear on the case/collar or actually wear away the outer diameter of the shaft where the c/s rides?

edit: Just read another read about the wear and how the shaft actually wears.

I bought a used L to find the sprocket falling off .

I found the keeper not correctly installed ,it must offset the theeth.

Killed the shaft end.

I tacked a bump of weld to the shaft ,sprocket wont come off until I grind off the bump.

Be carefull not to weld sprocket it should be free .

good luck

So does it wear on the case/collar or actually wear away the outer diameter of the shaft where the c/s rides?

edit: Just read another read about the wear and how the shaft actually wears.

Usually the O.D. of the shaft. If you found a good thread with good info, link it here.

I also run 15/48.. Very happy. I am new to CO. came from the Mojave and ran open desert. Avg speed open raw desert 45mph. Ran technical rock crawl single track in Second primarily. Only used 1st when hyper cluthching was involved.

I find a smooth launch much easier on the street with 15/40 .

I can run threw intersection w/out being into 3rd and down shift for a speedy pass on the highway.

So In my mess of a mind, I would think a softer steel sprocket rather than a harder A/C grade aluminum sprocket would be better on c/s wear. The softer metal would give and take the abuse over the hardened c/shaft. A designed in weak point.

I am no engineer though. I just work with what they designed! LOL

dont think youll find aluminum counter shaft sprockets anyways.

Ya, I know the math... I just didnt want to do it and map it out like you have. Thank you CL! Its much easier to post a link. Wow, I'm becoming a real bum!LOL.

4K, congrats. :applause:

I do work, as Toyota tech... That is the problem. Along with a suffering economy. I will "work" maybe 2-3 hours of the day that I am there for 8. No broken Yota's, if there are no one wants to spend money to fix them.

I spend time in TTT, xr650/600, vintage, DS, moderator, help out a bit in the smaller Honda forums. Just gets boring at "work" with no work!:)

Toyota's break? :cry:

Toyota's break? :applause:

LOL, thats the problem...

dont think youll find aluminum counter shaft sprockets anyways.

Prob. for that reason.

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