And this folks, is why torque wrenches are a must have item.

 

oooof that's for sure, and how about some quality fasteners ? Yeah- I think that's a bolt you want to pay a little extra for. Glad OP is OK

 

Regarding a torque wrench (of which I have three): I think I'm missing something here. This was caused by [a ridiculous amount of] play in my bushings and stress over time. Or are you saying that the left bolt should've held the handlebars in place after the right bolt snapped if it were torqued correctly?

If that's the case, I'd say that it was and finally loosened after it had had enough. Who knows how long the right bolt had been severed. I'd never removed those bolts before, btw.

 

Just glad your ok man. Think I'll go and take a closer look at mine today. Thanks for the heads up!

 

I don't see where the amount of play within the bushings has anything to do with a failure. There is (or is supposed to be) a metal sleeve inside the bushing and that is what you are applying torque against, when you use a higher torque value than what was designed into the bolt you have create undue stretch on the bolt setting it up for potential failure later on down the road - its anyone guess how long that could be. When the bolt is put under more stress than it was designed for it won't cause an immediate failure but when it does the failure is often catastrophic as seen in that video. I'm just saying its best to use the torque recommended by the manufacturers engineers.

 

Spot on.

 

^^ Really?? The play in the bushing has EVERYTHING to do with why the bolt snaps! If there was no play, say welded...it wouldn't snap. Physics.

Adding apes is like putting a huge prybar on that junction of riser/bars/triple....any slack or play in that area is going to cause stress on the bolt. Hence, you ALWAYS replace the bushings when adding bars with aftermarket poly bushings

 

I used poly bushing and new riser bolts when I changed out my bars.
Heavy 1.5" dia. bars. No way I was going to re-use the stock rubber bushings.

Mine barely move when moving the bike by the bars in the garage.

 

The bushing is only there to dampen vibration, it is not the actually part that force is applied to - that is what the metal sleeve does - it allows a prescribed about of crush to occur and absorbs the force (applied clamping force) of the bolt, the bushing provides an indirect connection to the top clamp......study the parts invoiced and you will see that the only part bearing force from the bolt is the metal sleeve, if you over torque the bolt lying on the bench, eventually there is the possibility that the bolt could fail.
Doesn't matter if your apes are 3 feet tall, the force at the riser bolt is still the same because it doesn't bear on a fixed (rigid) point, it floats in the bushing.

 

I wasn't so lucky, about a month ago I was going through a turn in the canyons around 60 mph when all of a sudden I went down, broke both legs, I'm convinced it was a broken riser bolt that caused it.