Derailleur Pulley Bolt

[cycle tramp]

I reckon that's a photo of the bolt in situ with the allen key fitting 'rounded off..

Personally I've never bothered with buying 'proper' derailleur bolts - and have replaced them with stainless steel bolts of the correct length and screw thread.. to make the shank of the bolt smooth, I've just filled that bit of thread with some epoxy metal glue and allowed it to harden (you want just enough to fill the valley of the screw thread, but not enough to over top the peaks)

[cycle tramp]

Sadly, on trying to replace a pulley, the bolt head is stripped. Any tips on how to get it off?

Also, I'll need to buy a new bolt but I'm unsure, while searching online, what will be compatible with my Shimano RD-M663 derailleur.


IMG_20220614_124140.jpg

Am I right? In the photograph, is that still the head of the bolt with its allen key 'insert' stripped?

[Gummo]

Am I right? In the photograph, is that still the head of the bolt with its allen key 'insert' stripped?

I have no idea how that hex shape at the bottom of the bolt-head well got there - it reminds me of that white/blue dress illusion that went viral some years back. Here's another snap from just now.

[Jdsk]

IMG_20220614_124140.jpg (62.12 KiB) Viewed 552 times

IMG_20220616_184922.jpg (91.15 KiB) Viewed 552 times

Are the two photos taken from the same side?

Is it a nut?

Thanks

Jonathan

[531colin]

If its the top one, is the hexagon we are looking at part of the bit which plugs into the mech. in Jonathan's picture?

Top one - no.10 on the diagram.

Can you undo the other jockey wheel bolt and take the cage to bits, as somebody suggested?

I'm stumped as to how I'd do that since the offending bolt is stuck in the main body.

OK, top jockey wheel we are looking at.
Remove bolt 11 in the diagram, to release the inner cage plate (9) and the bottom jockey wheel .....keep the jockey wheels separate, they are different!
The top jockey wheel may also now be loose; in which case, happy days, remove that too and you may be able to see whats going on!

[Gummo]

Are the two photos taken from the same side?

Yes.

Is it a nut?

I've no idea how that image got in there - it's certainly looks like one.

[Jdsk]

Thanks

Jonathan

[Gummo]

Remove bolt 11 in the diagram, to release the inner cage plate (9) and the bottom jockey wheel .....keep the jockey wheels separate, they are different!
The top jockey wheel may also now be loose; in which case, happy days, remove that too and you may be able to see whats going on!

I've done that - only realised via this thread that the cage was of two separate sides. I did as you recommended but the inner plate merely rotates freely around the steadfast bolt.

[531colin]

Remove bolt 11 in the diagram, to release the inner cage plate (9) and the bottom jockey wheel .....keep the jockey wheels separate, they are different!
The top jockey wheel may also now be loose; in which case, happy days, remove that too and you may be able to see whats going on!

I've done that - only realised via this thread that the cage was of two separate sides. I did as you recommended but the inner plate merely rotates freely around the steadfast bolt.

OK, so there is enough of the bolt head remaining to secure the inner cage plate. I think you need to drill away the remains of that bolt head in order to disassemble the thing. The diagram looks like countersunk Allen bolts.....is that what the one you have removed looks like?
select a drill bit which most closely resembles the bolt head, and go to it.....unless you want to get left hand drill bits (oh yes you can!) where there is a chance that as the drill bites (battery drill on "reverse"...slow speed high pressure) it will back the bolt out of the hole.
If you drill the head off and remove the jockey wheel and cage plate, you should be able to unscrew the bolt with pliers.

[gregoryoftours]

Can you undo the other jockey wheel bolt and take the cage to bits, as somebody suggested?

I'm stumped as to how I'd do that since the offending bolt is stuck in the main body.

Remove the lower jockey wheel assembly and rotate the outer cage plate anti clockwise. There may be enough friction between the head of the stuck bolt and the cage plate that the bolt turns with the plate. Try to get the threads of the stuck bolt soaked with lube/penetrating fluid first, and apply a slight twisting force to the plate as you rotate it to try to increase friction against the bolt head.
Failing this you can drill the bolt head as described, enough that the cage and upper jockey wheel assembly can be removed. Then there will be plenty of bolt to grip on and remove with locking pliers.

[bluespeeder]

On the subject of jockey wheel bolts, should they have loctite? I have just undone mine to replace the wheels and they were loose as!

[Jdsk]

On the subject of jockey wheel bolts, should they have loctite? I have just undone mine to replace the wheels and they were loose as!

"Install and tighten pulley bolts to about 30 inch-pounds. Use of a mild threadlocker is recommended."
https://www.parktool.com/en-int/blog/re ... r-overhaul

That's about 3 N m.

Jonathan

[gregoryoftours]

On the subject of jockey wheel bolts, should they have loctite? I have just undone mine to replace the wheels and they were loose as!

Yes they often have a little on from new.

[gregoryoftours]

Having read your previous post that I missed it seems like you will definitely have to drill the bolt now. Use a bit that is the same diameter, or maybe only a tiny bit larger than the diameter of the shaft of the bolt. It will be the same as the bolt that you've already removed from the bottom jockey wheel. Don't use a bit that is as big as the bolt head because you'll drill through the plate as well, which you don't want.

[Gummo]

Just waiting for the new bolt to come in the post - then, drilling beigns. Thanks for all your kind assistance.