So I stripped one trying to tighten down on some bars that were slipping and was curious what size threads the stock bolts that are used by the top clamp is. I have a 2001 1200c but swapped out to top clamp with gauge mount towards the front.

 

5/16 socket cap bolt
Coarse threads




I don’t really know the length. I just measured with a tape from top of clamp to bottom of riser.

 

I think stock was 1 1/2" but may be a little too long. 1 1/4" would be sufficient and ideal. Some have even used 1".
As long as you get 7 to 8 threads in for max holding power. Too deep and you bottom out and strip.

Also, there's a proper way to tighten these bolts for maximum clamp to bar contact. Snug them up, back then front just enough to hold the bars in place. Then torque the back 2 to 14-15 ft.lbs., then the front 2 to 14-15 ft.lbs. There should be a slight gap in the front. If you just randomly tighten, zigzagging or whatever, only a small portion of the clamp will be making contact with the bars and they will be much more prone to slipping.
Tightening the bolts anymore than the recommended torque will only get you stripped bolts. Also, use the blue(medium) , loctite. Not red.

 

Unless you already have access to a helicoil kit, replacing the risers may be cheaper. Or use a longer bolts and lockwashers.

 

I would get new bolts and risers myself. I wouldn't go helicoil or lock washer and I already have both at my disposal.

 

I'm the same way. Yes, I understand that a helicoil may be stronger however with risers being as inexpensive as they are I'd simply bought new ones when I stripped mine a few years ago. But then I am overly cautious with the parts that could kill me if they fail

 

I totally agree with the above statement. I really have never cared for helicoils if they can be avoided. I would not trust them on MY bars.

 

Yes, helicoil inserts can be 'stronger' thread wise in some instances. However, in this case, I'd say the opposite. The reason for this is that you will be reducing the material thickness of the riser itself.

 

Really depends on his bike guys. Remember, he has a 2001 "C" model. Depending on when his was built, it could have the one piece "Custom" riser that is not easily replaced aftermarket and even on ebay are expensive. Even the regular style risers are more expensive than a helicoil or tap/drill.

The risers have so much extra meat in them that you can easily drill and tap for the next largest bolt size without even needing to go to a helicoil, and if you go with a helicoil there should be no worry about wall thickness. You won't even be in the same zipcode of a problem as long you don't go at it with the biggest drill bit you've got! haha

 

Good point, I missed the fact that he had a "C"