Front sprocket confusion...

2 replies to this topic
  • Ron Roberts

Posted January 30, 2015 - 06:04 AM


I ordered an Iron Man front sprocket.  It just showed up yesterday and I have had my stock sprocket off for a week or so.  Anyway, I noticed it is carved out on one side and perfectly flat on the other.  I examined the stocker and it is the same way.  Now im confused on which way it goes on.  does the flat side face the outside or in toward the motor...or does it even matter?



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  • indy rider

Posted January 30, 2015 - 06:27 AM


On my 07' the carved out side goes toward the motor.

  • grayracer513

Posted January 30, 2015 - 07:33 AM


The undercut side does in fact face the engine.  It's like that because on some earlier models, the output shaft seal dust shield (the sheet metal covering the seal) extends beyond the collar that the sprocket clamps against, and if not for the undercut, tightening the sprocket down would bind up the transmission.  A lot of the later models have the cover trimmed back a bit, and now run sprockets that are flat on both sides.  The splines haven't changed, so to simplify inventory, some aftermarket vendors make only the version with the undercut. 


You can tell immediately whether yours needs the sprocket oriented with the cutout in the back by putting it on the other way, running the nut down snug, and see if you can turn the sprocket by hand in neutral. 

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