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CRF rear sprockets. 36t?

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Does anyone know where I can get a 36t rear sprocket for a CRF450 . Actually it's just the hub. I'm building a xs650 with supermoto wheels and because of the 650 gearing, I need to try and find a 36t rear. I saw where a guy and an old post on another site said he had a 36, But all i've been able to find is a 38t. The stock rear gear on a XS is 34, but with the little taller tire and I can add 1 tooth to the front I should be real close to stock gearing.

 Thanks for any help

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loose bolts cracking etc,  not saying it will happen just what I would watch for.   XS650 is going to thump it harder than it was likely designed for, why those hubs so light.

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I don't think you can fit a 36T, it would be 181MM diameter to the middle of the links - 10MM for the roller diameter = 171MM, and the bolt circle is 153MM + 8MM for the bolts = 161MM, leaving you only 10MM / 2 = 5MM clearance for the sprocket bolt heads and chain side plates.

 

Geared up that far, I don't think it will "thump" much harder than the 450.

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I don't think you can fit a 36T, it would be 181MM diameter to the middle of the links - 10MM for the roller diameter = 171MM, and the bolt circle is 153MM + 8MM for the bolts = 161MM, leaving you only 10MM / 2 = 5MM clearance for the sprocket bolt heads and chain side plates.

 

Geared up that far, I don't think it will "thump" much harder than the 450.

 

Now that's some science!

I was lost before 181mm to the middle of the links ;)

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If you want to know how I got 181 MM, this is the formula:

 

5/8 (chain pitch in inches)

* 36 (# of teeth)

= circumference of sprocket at the center of the chain links in inches

/ pi (converting circumference to diameter)

= diameter of sprocket at the center of the chain links in inches

* 25.4 (inches suck, we want millimeters)

= 181.914 mm

 

Or, type this into google:

((5/8) * 36 / pi) inches to mm

 

Don't make me draw this up in solidworks!

Edited by mudguy
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