Removing Rounded Allen Bolts
 

Trying to remove the stock rearsets as I've bought some shiny new ones. The Allen bolts holding the rear brake master cylinder are totally rounded.

Any ideas?

Re: Removing Rounded Allen Bolts
 

Will be watching this as I've got the exact same problem, the only thing I can think of is drilling them out and hoping not to muller the MC but as it's not a pressing issue I've avoided that so far.

Re: Removing Rounded Allen Bolts
 

I've tried drilling already but I don't think I'm doing it right as it just made them even rounder.

Re: Removing Rounded Allen Bolts
 

I use a dremel to cut a GOOD slot in them then if they are too tight to get with a good tough hollow ground screwdriver bit in a socket, I get out the impact driver. When replacing use copper grease on the thread so it never happens again. In fact while you are at it, go round your bike removing all unimportant screws and greasing the threads while you can still get them out.

Re: Removing Rounded Allen Bolts
 

The problem with these ones is they're set back into the footpeg mount so there's a good chance you'd be chopping into that before you got a decent slot into the top of the bolt.

Re: Removing Rounded Allen Bolts
 

How rounded is rounded?


If still has a bit of a socket put in the allen key apply a little turning pressure and hit / tap with a hammer.


If this don't work then as above slot or drill.

Re: Removing Rounded Allen Bolts
 

If you can hit in a torx bit without damaging the mounting that may give enough grip to undo the bolt.

Re: Removing Rounded Allen Bolts
 

I've tried all of the above, as Tom said they are recessed so you can't get in there with a dremmel.

I've tried the Torx bit technique and that didn't work, I couldn't really hammer it in far enough and don't want to be wielding a big hammer that close to the frame.

I think I am just going to have to hack the recessed section apart, it's going to be scrap anyway.

Re: Removing Rounded Allen Bolts
 

Hi
Try welding an old allen key into the rounded hole and then remove using a socket or spanner.
Cheers
Stuart

Re: Removing Rounded Allen Bolts
 

I don't have a welder

Re: Removing Rounded Allen Bolts
 

You should be using a drill the next size up from the bolt shank diameter. once you have drilled deep enough the head should part company with the shaft.


With out the head and the foot rest assembly removed you should be able to get some Moleys on the remains.

Re: Removing Rounded Allen Bolts
 

If the original rearsets do survive, let me know as I might like to buy for race spares!

Good luck.

Re: Removing Rounded Allen Bolts
 

I did something similar with stainless disc bolts which rounded off, really hard to drill stainless steel too.

Re: Removing Rounded Allen Bolts
 

If it's not drilling out the the drill bit is probably blunt. Also, when drilling metal, it should be on a slow speed setting, as slow as possible really. If it spins to fast it will overheat the tip and blunt it within seconds. If you see smoke slow down!

Ryan

Re: Removing Rounded Allen Bolts
 

er.... LOL...




Also buy decent quality drill bits. I found out the hard way how a cheap drill bit can ruin something you are working on.

Re: Removing Rounded Allen Bolts
 

Allen bolts are really hard, normal drills tend to get hot and go blunt. Try and find some cobalt drills. start with a small drill and work up in sizes. You will need coolant/ lube. You should only need to go to the nominal thread size as the thread root is smaller so you should break through without going bigger than the original thread.
Dremel glass grinding bits are good for getting an initial small hole cut down into the allen screw.

Re: Removing Rounded Allen Bolts
 

Go to Toolstation.
Buy these

http://www.toolstation.com/shop/p53312?table=no

Buy this.

http://www.toolstation.com/shop/p750...ooling%20fluid

I swear by these, there is no material i have found they will not tear through.

C.

Re: Removing Rounded Allen Bolts
 

Before you go mad with the drill and get the head off you may get a stud remover bit into the head of bolt (they are a tapered hardened bit with a LH helix on them, the harder you tighten them the harder they grip the hole and because they are LH they turn in the 'unscrew' direction of a normal RH bolt or stud).

if that don't work you are going to have to drill them out, use the same diameter drill as the bolt or up to 1mm larger and when you reach the shank of the bolt the head should just fall off - Allen bolts are high tensile steel and pretty hard to drill, so you need a good quality drill bit (the ones you get from B&Q etc are normally only OK on wood (best Chinese hardened mild steel bits) get Dormer or De-Walt from screwfix or engineering supplier).

https://www.lowes.com/pl/Screw-extra...ols/4294607735

this is just an example, screwfix or similar may do them, Irwin are a pretty good quality.

Re: Removing Rounded Allen Bolts
 

I would avoid stud removers like the plague. They are very hard which marks them very brittle. Once you snap one of them off in the bolt you're in deep deep dwang.

Re: Removing Rounded Allen Bolts
 

hard does not have to mean brittle - like everything else depends how much you spend, I have used them in industry for many years with great success, very often they are your last hope.

The other thing that helps is applying heat to the area, the expansion helps breaks the bond that is locking the bolt to whatever it is screwed into (heat also destroys loctite and other thread locking compounds) - maybe why welding something into a bolt head can work sometimes, the heat of the weld helps.

Re: Removing Rounded Allen Bolts
 

Try using a torx bit, slightly larger, hammer it into the rounded hole. Hammering helps loosen it. I used an impact driver (drill sized not humungous garage type) in anti-clock mode. Worked for me :-)