Broken bar mount bolts.

[gg3]

Here is an odd one.I have had 2 good crashes in the last 3 months,still off the bike from the second.The first one was a loop out & it landed on the bar end & Sheared off one of the bolts that bolt the bar clamp to the triple clamp.Also bent the stock bars which have been replaced with Renthal fats.
The second was a down hill endo & this time the bars are ok but the bolt has bent.Has anyone else bent or broken these bolts?
I have had plenty of 'incidents' in the past on other bikes but never broken or bent these bolts.
I noticed the aluminium washers under these bolts have compressed & deformed.I do have bar risers,would this tranfer some leverage to the bolts on impact?
Yeah,short answer is don't crash.

 

[twowheels]

I do have bar risers,would this tranfer some leverage to the bolts on impact?

Undoubtedly! You're better off having the bolts bend (second crash) than break (first crash), because its hard to ride in the woods with the bars in your lap.

If you need taller bars, its best to buy the handlebar, although bar risers are tempting, but any lift is going to increase stress on the bolt in a crash.

 

[GMP]

If you have to run risers for some reason, you can get a BRP top clamp that uses larger bolts. I cracked a renthal bar but did not bend the stock bolts, using the OEM mounts and low bar setup.

 

[GasGasDreamer]

if you go to a real hardware store, get grade 8 bolts.
it's near impossible for them to bend and/or shear.
the factory adds some lightweight [read cheap] bolts to lower weight.
some of the worst factory bolts are on the rear sprockets.
those should be replaced before they have a chance to fail.
as far as spacers, if you have a good bolt, it doesnt make any difference.

 

[gg3]

Thanks guys.The bolts look like a galvanised mild steel bolt.Might drop the risers & get a higher bend.

 

[bchatt]

I have also bent these bolts. I have 6mm alloy spacers under the bar clamps.
I have found if they are not done up extremely tight they are more inclined to bend. The heads are "T" shaped, so its not quite as easy to replace with 8.8 tensile, although I guess you could cut some of the heads away. So far, I haven't bent my Hebo bars...

gg3, how are you going with that taller gearing?

 

[gg3]

The alloy spacers squash & allow the bolt to bend.I am replacing them with 2stainless steel washers & 314 stainless steel bolts with the heads ground off to a 'T' bolt.Are the spacers/washers really needed?
The taller gearing works excellent.It seems I have gone against the grain with taller gearing as most gear down.The idea came from a 300 KTM enduro rider(very good rider).It has made first more usable & spaced the gearing out.So when you get into forest single track you don't need to be swapping through gears as much & you can ride smoother.In conjunction with the JD jetting kit you can use the bottom more & it lugs off the bottom real clean.
Off course it all depends how you like to ride & what terrain.

 

[hannesd]

The alloy spacers squash & allow the bolt to bend.I am replacing them with 2stainless steel washers & 314 stainless steel bolts with the heads ground off to a 'T' bolt.Are the spacers/washers really needed?
The taller gearing works excellent.It seems I have gone against the grain with taller gearing as most gear down.The idea came from a 300 KTM enduro rider(very good rider).It has made first more usable & spaced the gearing out.So when you get into forest single track you don't need to be swapping through gears as much & you can ride smoother.In conjunction with the JD jetting kit you can use the bottom more & it lugs off the bottom real clean.
Off course it all depends how you like to ride & what terrain.

what gearing are you riding now?
i'm allso cosidering taller gear...

 

[bchatt]

Are the spacers/washers really needed?
.

Try it and see.............
With that gearing, do you find it too tall when negotiating rooty climbs, slippery rock rivers etc? I always seem to have a finger on the clutch is these conditions, with 13/49.

 

[gg3]

13/46, being a bit taller it doesn't get into the higher revs as quick so doesn't spin up on the slippery stuff as much (coromandel wet clay),but keeps the momentum going.First was great for really tight technical stuff but at the expence of your forward momentum,this seems to be a good balance.
On re-reading this I hope it makes sense to anyone else?

 

[bchatt]

Makes sense to me. I will often use 2nd gear even though my entire body screams at me to use 1st. Much easier to "milk" that traction in 2nd, but, having said that, I would not want to be without that 1st gear for tricky bits when I simply can't go slow enough in 2nd.