[Closed] Two stripped rotor bolts - what to do?!

dremmel a slot into them and use a screwdriver?

Hacksaw or Dremel a groove straight across the top and use a flat blade screwdriver to remove them. Alternatively, drill the heads off and leave the stub. 4 rotor bolts will be fine

cheapo torx set - try a new, good one?

matthew_h - Member

Hacksaw or Dremel a groove straight across the top and use a flat blade screwdriver to remove them. Alternatively, drill the heads off and [s]leave the stub. 4 rotor bolts will be fine[/s]Once you've got the rotor off the studs will come out no problem

Not always but you're probably right. I've got an old Bulb with a stub left in it that wouldn't budge. Not a problem either way though.

I've got an old Bulb with a stub left in it that wouldn't budge

You just need to stick your tongue out the left corner of your mouth while trying to get extract the stud and it'll come out easy. 😉

It's more that I can't actually get anything on it to get it to turn. I've tried the tongue out of both sides and even biting it a little bit.

How did you spin the rotor with 2 bolts left in?

Anyway - given what you've said already, I'd walk away from it now & give it to someone else to repair before you damage the hub

cynic-al - Member
cheapo torx set - try a new, good one?

Posted 4 minutes ago # Report-Post

user-removed - Member
Off to buy a half decent torque set....

Posted 8 minutes ago # Edit

I meant torx tho.... 🙂

Cheers for the advice and info - off back down the bat-shed to wield my mighty hacksaw.

Incidentally, and I know this has been covered many times but the search function isn't helping, I'm guessing that a bent rotor will never be completely straight again - is that right? Running Juicy 7s so the pads are very close to the disc...

Think about it, you only need 1 bolt to hold the disc on, as long as there are 5 stubs to manage the braking torque everything should be OK!

Seriously though discs can be trued-up fine, use an adjustable.

Uplink - was that aimed at me? Did you read the OP or just guess at what it might say?

and even biting it a little bit.

If it didn't come out after that it must be f*cked.

Think about it, you only need 1 bolt to hold the disc on, as long as there are 5 stubs to manage the braking torque everything should be OK!

yes i know your post in a bit tongue in cheek hmmm, but that is not how bolts work... they don't work in shear.

bolts work in tension and through the clamping force increase the friction between the items clamped.. it is that friction that stops the disc rotating..

Interesting, I was being semi serious. I don't care enough to try it though.

Uplink - was that aimed at me? Did you read the OP or just guess at what it might say?

well yes it was meant for you

you said 4 had come out then

then one of the heads 'rounded' - b@lls, I thought, but no problem, I'll just spin the rotor to unscrew it. Then the same happened to the next one.

so I took that to mean 2 were left in & you spun the rotor round

you said

Uplink - I meant that I was assuming the last one would come out no bother, the same as the first four, thus leaving me free to spin the rotor and the ONE (penultimate) stuck bolt. Unfortunately, the last one also got stuck.

Meh.

Anyways, they're all out now - one job always leads to another and now off to drill holes through my workbench to fit my vice. The vice has been sitting in the garage for about eight months now 😳

Is clamping my rotor in the vice to straighten it a very bad idea? (I'd clean the jaws first).

If the bolts arn't low profile, just use an adjustable wrench 🙂 Works everytime for me!

Is clamping my rotor in the vice to straighten it a very bad idea?

you've nothing to lose but you'll struggle to get enough leverage I think

a vice won't allow you to bend it past the point needed & spring back, like some form of lever would
Does that make sense?

Oh I was going to suggest mole grips or sawing flats in opposite sides of the bolt head so you can get a spanner on it. Way more torque than a screwdriver.

Cheers uplink - yes that makes sense - I've clamped it in the vice just to get it back to something approaching flattish! It's actually one of the 'arms' coming out from the centre of the disc which is bent - this has then malformed the whole of the rest of the disc 🙁

Think it must have hit a pointy rock during my comedy over-the-bars fall last week.

I'm guessing that a bent rotor will never be completely straight again - is that right?

Depends how bent it is, you'll never get it 100% again, personally i'd buy another one.

Easiest way to straighten a rotor is when it's still attached to the hub.

You can apparently straighten them but I've never managed to get one just so, and you can pick them up cheaply...

bolts work in tension and through the clamping force increase the friction between the items clamped.. it is that friction that stops the disc rotating..

MilitantGraham - Member

bolts work in tension and through the clamping force increase the friction between the items clamped.. it is that friction that stops the disc rotating..

That's the theory and, ideally, bolts should only ever be used in tension, not shear, but in reality, I wouldn't want to rely entirely on the friction between the smooth metal surfaces of the disc and hub, or between the caliper and frame/fork for that matter.

Well it actually depends on the bolt design. It's not uncommon for lots of bolts to be designed to take shear loads too. I have designed many bolted joints that have been engineered for shear. Whilst I cannot be certain, but I'm pretty sure that standard avid disc bolts have their shoulder precisely for shear reasons. And they would help with disc location too..
See this pic..[img] [/img]

Can you get some mole-grips to grip the heads? I've managed to get rotor bolts out this way before.

the same as the first four, thus leaving me free to spin the rotor and the ONE (penultimate) stuck bolt

isnt the penultimate bot the 2nd last one? 👿

the same as the first four, thus leaving me free to spin the rotor and the ONE (penultimate) stuck bolt

cullen-bay - Member - isnt the penultimate bot the 2nd last one? 👿

YES!! Am I speaking bastardised Latin, or perhaps uttering pre-druidical grunts?!!11! 😈

Let me try once more; I removed the first four nae bother. The fifth stripped. At this point, with two bolts still in, I thought to myself, "Oh well, I'll remove the last bolt (not, at this point, stripped) and then unscrew the FIFTH bolt by rotating the disc. That is all.