As title rounded the rotor bolt, how on earth do I get it out?

Grind the head off it. Use pliers to get the stub out.

Ok, haven’t got a grinder to hand…any other suggestions otherwise will try that tomorrow.

Cheers.

hacksaw a slot in it and use a screwdriver – sometimes two blades in the saw gives a wider slot to get a bite with a bigger screwdriver

Good pair of locking grips. Easy.

tap a torx bit into the rounded hex socket

Cheers, that was my first effort but haven’t got a screwdriver wide enough at theft mo, again will be able to access tomorrow, sorry are there any other options?

What tools do you have to hand?

Mole grips are the answer.

Or hack a slot into it for a screwdriver. But mole grips are easier.

Drill, hacksaw, hammer, small slotted screw drivers, Allen keys, pliers, chain whip, Haha and so other useless tools.

Looking at responses probably gona have to leave it till tomorrow 🙁

Got any long drill bits that you could put through from the otherside of the hub?

Jotas solution has worked for me. And if he/she has a genuine 180 crank Jota I am very envious!

Hacksaw a slot in it and just twist the hacksaw. You dont need a screw driver. Will give you more leverage aswell!

Take all the other bolts out and turn the disc. Sometimes its enough to start the bolt moving.

And if he/she has a genuine 180 crank Jota I am very envious!

it’s a 76
I also have a 75 3C

not been on them since last May though 🙁

Screw the other bolts back in. This will release the tension off of the rounded one. You might then be able to get enough purchase with the allen key/pliers etc. to get a turn on it.

This happened to me and if like me you are struggling with one remaining bolt this did the trick.

Got any long drill bits that you could put through from the otherside of the hub?

Bolts are steel, hubs are aluminium – be careful with the drill…

I’ve one hub with a seized bolt (stub) still in, just leave it with no head on.

None of these are the right answer.

Quite clearly the only sensible option is a new wheelset. Will work out cheaper when you add the tools, wear and tear on them, your time, your frustration, yep, definitely an excuse for the wheelset you’ve had your eye on (if you’ve not best get shopping!) 😆

Why is it urgent that the bolt be removed…is these another solution.

A sharp tap with a sharp centre punch on the edge of the bolt, stand wheel verticaly and hit (anti clockwise!) in about the 11 o’ clock position.
Works every time for me.

Goz you’ve had this happen more than once? 😉

This comes up again and again and people always come on with all the same stupid suggestions. I don’t think anybody has suggested penetrating oil yet though.

Support the job very solidly. Get a punch or something very solid and a big hammer. Smack the bolt very hard indeed vertically straight downwards to shock the threads free. Unscrew with a star driver, a bigger allen key or something that will engage with it. You could combine the shock and the unscrewing action if you happened to have an impact screwdriver handy, it’s what they were invented for.

I work in an engineering workshop, we use an edm drill for removing broken taps etc, a form of spark erosion, the bolt is burnt out to to the core size of the thread, then effectively you are left with what resembles a spring in the tapped hole. this can be easily removed. If you fail to get it out, take it to an engineering machine shop that specialises in edm/spark erosion.

Hammering a slightly bigger torx head in is definitely the easiest way to do this!

Had this happen on a number of occasions. Just make sure the new bit is properly hammered in so it doesn’t round off even more of the bolt. Be prepared to replace the bolt afterwards

Penetrating spray
Leave 10 minutes
Big hammer whack x 2 or more on bolt head
Molgrips
If that fails use the rotor twisting trick BUT be careful not to damage the hub or bend the rotor.

OR

groove in the bolt head option.

I used the top option last night to good effect but marked the hub when turning the rotor. You have been warned!!

Not me personaly, customers bikes in the workshop.

I had similar with a rounded countersunk screw in a rear mech. I used a dremel type tool to cut a slot in it – easier than a hacksaw and does not cut the surrounding area.

I had similar with a rounded countersunk screw in a rear mech. I used a dremel type tool to cut a slot in it – easier than a hacksaw and does not cut the surrounding area.

I had exactly the same problem a while ago. I used the turning the cage to get the bolt out trick so I’d be inclined to try this on the rotor bolt in conjunction with penetrating oil and the shock tactic, after having a go with mole grips.

Just removed 3 rounded rotor bolts today!Used mostof the advice above
One came out using a hammered in larger size 27 torx rather than a 25.
One came out using a hammered in allen key type bolt ,can’t remember the size.
The last one was a bugger and resisted everything I threw at it. tried oiling it,larger and larger torx but it just kept wearing away. Evetually hacksawed it across,banged a larger groove with a screwdriver, and tapped the screwdriver with a hammer at an angle and it freed it

I’ve used two techniques succesfully, one’s the hacksaw a slot screwdriver one (usually my first choice) that you said won’t work with the tools you’ve got. When that doesn’t work I drill out the bolt head from the hex side.

Choose a drill bit slightly larger than the hex hole and drill down into the head, CAREFULLY. The aim is to stop just before the bolt head stops and the screwthread starts, go too far and you will drill into the disk. Then with a hammer and screwdriver/drift hit the bolt on the side of the head to shear it off (if you hit it on the inside of the drilled hole there is less chance off slipping and marking the disk). Undo all the other screws, remove the disk then get a pair of pliers/molegrips on the stub of screw thread and unscrew it.

Find the hack saw and screw driver method very hit or miss. Either a hammered in torq socket or pipe wrench/pliers to be the best methods

Mole grips/Lock grips giving it a twist in conjunction with the allen key or a torx bit hammered in giving it a twist will get it out.

jeez, just drill the head off, get the stub out with pliers

Whatflatyres said, the second one, about a 7mm drill bit should do it, just kep drilling until the head of the bolt pings off, you’ll know if you hit the disk.

What bolts are they? I’ll add them to my lengthy “do not use” list.

oliver, you can use any bolts, you just need to do so properly.

Not the Hayes ones, they’re made of brie.

Drill the head off. Remove rotor. Take a blow torch and gently heat the stub and Ali. This melts the old locktight. Molegrip the stub and turn out. Job done.

Worst case, drill head off, replace rotor and use 5 bolts.

T

Drill the head off with a big drill bit and the stub will probably come out with your fingers. Worse case, molegrips on the stub.

I had a stuck rotor bolt recently. Drilling seemed to be going nowhere (need better drill bits and a more powerful drill, I suspect) Long handled adjustable pliers sorted it out in the end. You need something with decent ridges in the jaws to get a bite into the bolt head, then clamp the teeth on *really* hard. The long handles give more than enough leverage, so the main job is just stopping the teeth from slipping.

Sawing flats into it and using a spanner works too.