Cruising the busy multi use path today on my way to the woods.
A loud snap occurred, followed by my arse and balls being wedged between the seatstays and forward turning rear wheel similar to a cheese grater!
Quite scary really but no major damage done.
Lucky I wasn’t doing anything tricky at the time.
The cause was the bolt breaking at the front of the clamp mechanism.
Would you just go to Halfords and find a matching bolt or do you think there’s something special about it?

Who ate all the pies eh fatty.?

more likely over-torqued perhaps?

if you’re getting creaks, grease the rails and clamps rather than bend the allen key.

M4 machine screw isnt it? the brass bushing can be reused I guess. So any machine shop screw cromoly should do.

Seeing that, I’d be sourcing a hi tensile one personally.

Who ate all the pies eh fatty.?

😆 I may have but I was trying to burn them off.

more likely over-torqued perhaps?

Maybe, but I haven’t touched it in over a year.
The brass bushing looks fine.
Wouldn’t want another failure like that I may not be so lucky next time.

I would go with a different design post that doesn’t rely on tension of two bolts to hold position after that.

unlucky there!! (lucky?) snapped a few USE posts in the past of similar twin bolt design – I’d change post

dont be a tight wad and stop buying cheap junk

Would you just go to Halfords and find a matching bolt

I’d replace both bolts.

I feel your pain.

Will be a M6 bolt, M4 is way puny.

Get an M6 Allen cap screw in iso 12.9. Most industrial ironmongers should have something suitable. Iso 8.8 is not strong enough when your bum is at risk !! Oh and buy two as you will want to replace the other one too.

Or if your feeling flush or a weigh weenie something in Titanium will suit Sir.

I would go with a different design post that doesn’t rely on tension of two bolts to hold position

yeah. them thomson’s are shit

I would go with a different design post that doesn’t rely on tension of two bolts to hold position after that.

Thomson posts work on the same mechanism though. My other bike has one of those.

Get an M6 Allen cap screw in iso 12.9.

Thanks! I will go for 2 of those.