Sheared Bolt

aldric

I was removing a broken mud guard this morning and managed to shear off the head of a bolt which seems to hold the wire for the front derailleur.



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So far I have been unable to remove this screw, does anyone have any suggestions?

The bike isn't that long out of the bike repair shop and I would rather not take it back again.

Thanks.

laurentian

Are you talking about the "bolt" just below the "band-on band"?

Without wishing to state that which may be obvious, have you tried mole grips?

I would be inclined to give it a good spray with WD40 a few times and allow it to penetrate before trying - it looks like the thing may be corroded in there so don't be too hasty after spraying with WD40 - you don't want to break off the remaining stalk. Perhaps give it a couple of sprays over a few hours and leave it overnight before setting about it with the mole grips.

epo rocks!

That bike is filthy.

team47b

spray with wd40 as laurentian says, leave it overnight, put two nuts onto the thread and lock them together with two spanners, then undo the one nearest the frame, it should turn the thread as it can't actually move up the thread as it is locked against the outer nut.

Works on engine studs too

Then clean your bike with a strong degreasant :roll:

monkimark

Either mole grips or cut a slot in the end of it with a saw and use a flat bladed scredriver to remove.

Chances are, if it sheared the head off trying to undo it originally then you'll struggle to get it out anyway - plenty of wd-40 or similar may help.
Failing that, you can get a clamp on replacement for the pulley bit that's snapped off or an adaptor to convert the mech to top pull - or you could buy a top pull front mech if such things exist for road bikes.

laurentian

team47b wrote:

spray with wd40 as laurentian says, leave it overnight, put two nuts onto the thread and lock them together with two spanners, then undo the one nearest the frame, it should turn the thread as it can't actually move up the thread as it is locked against the outer nut.

Works on engine studs too

That is probably a better way of doing it to start with - if you get no joy, perhaps then resort to mole grips

aldric

Thanks for all the suggestions.

I have been spraying it with WD40 and using some pliers, however it isn't for moving at all :roll:

I will try and find a couple of nuts and try that idea, failing that it looks like is the lbs again - so frustrating as its just back from a hefty repair.

The bike does need a little clean and will sort that out after my next ride, whenever that might be!

Monty Dog

Try Plusgas rather than WD40 as it's a more effective. Definitely try the stacked-nut method to loosen but having used pliers, you may have mangled the threads. Worst case scenario is to fit a new clamp-on pulley wheel.