Changing countershaft sprocket only.

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strider80
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Changing countershaft sprocket only.

Post by strider80 »

I feel like I need to have two set of sprockets to cover the diverse riding that I do. One weekend is open desert and the next is tight moutainous woods. Right now I run 13/50 and that works good in the woods, but is too low in the desert.

Is there a combo that works well by just changing the countershaft sprocket so that I can use the same chain?

Maybe keep the 13/50, but buy a 14t front for the desert?

Or go 12/47 then 13/47 for the desert?

Is a 14t front sprocket better than a 12t? Will the 14t fit okay?
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Post by canyncarvr »

Simply a point of view...backed up by nothing.

I was looking at my 12T CSS just the other day thinking, 'Gee...a 13 sure would be snug to the swingarm chain slipper!'

I've not tried a 14T CSS. I don't know that it fits or not. I would not assume that it does based on how close the 12T is. It might if you took some of the edge off the slipper.

IMO and all, but yes, a 14T is better than a 12T. Common knowledge has it (and some disagree anyway) that a 12T sprocket is as small as you can go with a 520 chain and not have some considerable wear problems. The folks that disagree think 12T is too small already.

I run a 12T. Have for years. Have had no problems with them wear-wise.

FWIW and all.

SO...the answer to your question depends on if a 14T fits.

I run mid-to-upper 70s in the mph category with a 12/47 setup. How fast do you need to go!!?? Yeah...you did say desert. For me, running down a 4-6' wide track at 70+mph pretty much scares me to death already. I KNOW that antlered bug infested vermin is just waiting for me.

Although...last time it was a COW (no antlers!) that stuck its head out of the scrub just as I whizzed by.

Like:
Roseann Roseannadanna wrote: "I thought I was gonna DIE!!"
Last time I was in desert environs I WAS going that fast...looking around..didn't see 'til too late a washed sand edge that got bigger the closer I got. Flipped the bike whirly-gig thru the air, missed me by a couple feet when it hit the ground. As it was I busted the front/chin off my new Bell Moto7.

I keep that helmet on the counter at work to remind me of 'things' that can happen.

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m0rie
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Post by m0rie »

I run a 12/47 combo normally and will switch to a 13/47 at times when I'm running down in the SoCal desert. A 12/47 moves along just fine but a 13/47 will be a little less buzzy in 6th gear at speed. If I forget to change the sprocket out i'm not going to be crying about it. If you can only have on set though get the 12/47 setup and you'll run just fine.
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Post by canyncarvr »

12/47 isn't much different than the 13/50 he's got...and that's what he wants to change...right?

IF a 14 fits, fine. Use it with the 50.

IF it don't, then a 12/47-13/47 would be similar with the ease of a CSS change to get it done.

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Post by strider80 »

I am not so concerned about top speed, as I am regaining the use of 1st gear and 2nd gear when in the desert and in low traction situations, think GP style turns and some hill climbs in deep silt. I feel like higher gearing would give me more control when I am trying to ride smooth and carry speed. My setup now is too herky jerky jamming through the gears trying to get traction in the silt, 1st roosts out, jam into second, roost out, jam in to third and bog, it is actually quite comical to think about. I feel that with a higher gearing, 1st and 2nd will be more vesatile with some clutch work.

My 13/50 setup now works great when I am in tight woods, 1st is still a bit low though. I may be thinking about it all wrong, being a crappy desert riding does not help either, seems like gearing would be something to play with though.
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Post by strider80 »

Maybe I should just go back to stock 13/47 and get my carb and head RB'ed and it will work fine everywhere.
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Post by m0rie »

>|<>QBB<
strider80 wrote:Maybe I should just go back to stock 13/47 and get my carb and head RB'ed and it will work fine everywhere.
That would do the trick. With the RB mods you could get away with running 2nd and 3rd on those hill climbs when you would have been clicking down to 1st on the 13/50 combo.
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Post by strider80 »

I feel like even now with bolt on mods and close jetting, 1st is pretty unusable, if I need 1st for a steep climb and rarely can stay in first and need to hit second halfway up.

Alright, I am sold, RB it is once the X-mas bonus comes around (knock on wood....).

Do you guys have a good source for Wiseco rings? I should do a minor topend cleanup and rings when I pull the head.
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Post by canyncarvr »

I got a Christmas bonus once!! I think I did. It was a long time ago.....

An RB modified carb set to the SSS is honestly an odd duck. The most noticeable change the SSS gets you is pull in 3rd gear that does not at all fit what you DID to the thing (turned the air screw out too far!).

You will feel it in 2nd, too. Just off-idle to about 1/2 throttle will pull much better with Ron's carbwork.

Send your head in too while you're at it. Not as big an impact as on a 220, but you can feel it!

My 1st is low (12/47) but still very useable. I don't use it much for riding, but say for picking the front end up out of a hole, foot down turnarounds....

Come down here for a ride. You'll find 1st gear very helpful! :wink:

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