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Lower profile rotor bolts?

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Does anyone know of a rotor bolt with a lower profile head? The KTM hub I bought has a clearance issue with the rotor bolt head height and the caliper.

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Yes you should be able to go to a nut and bolt store and buy 8mm flat head bolts to replace the not quite flat heads.  You will need to assure the angle on the replacement  bolts is the same as the old bolts and fits the sprocket.  It is also possible to machine the countersinks in the sprocket deeper so the bolts sit further in.  It may also be necessary to countersink the hub to get the heads flush.

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A low head socket head cap screw is the wrong head style for a rear sprocket bolt.  The rear sprocket uses counter sink bolts.  The OEM counter sink bolts have slightly rounded heads for more hex key engagement.  A standard flat head bolt is simply flat on the exposed surface.

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I'm looking for a rotor bolt set.  I have some digging around to do, I've been pretty busy with some family health issues lately.  Really hoping to get this buttoned up this weekend.

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There is a mis-understanding here with the assumption that the KTM hub uses a counter sunk bolt like the DRZ hub does on the rotor side.

 

The KTM rotor had a circular flat indentation for a standard sized # 8 washer head bolt.

 

There is no problem with this using this on a  SM as the SM because of it's larger sized rotor clears without a problem. On the "S" there may be a clearance problem.  with the caliper bracket just bearly touching touching the bolt heads.

 

I neve tried my KTM hubs on my "S" but it looks like just a little bit of grinding on  the bolts would give enough clearance. As the bolts are washer head bolts enough clearance might be had by just switching to a standard headed bolt.

 

Tony

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I completely spaced out.  Post says "rotor" but I was thinking "sprocket".  You are right, KTM uses a bolt in a shallow counter bore.

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I think the counter bore is a little less on the aftermarket rotor than it was on the stocker that I pulled off.  Hopefully I'll get a chance tomorrow to look around for them a bit.

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Looked at some KTM rotor bolts. Seems like the depth on the heads is 5.3 mm. I also looked thru some bolts that I have that are Allen mushroom and round head bolts. They were just local hardware items and the depth on those were just below 3mm.

 

Tony

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