Author Topic: 2 cog derailleur bolt dropped off.  (Read 1038 times)

Aunt Maud

  • Le Flâneur.
2 cog derailleur bolt dropped off.
« on: January 15, 2019, 01:52:59 pm »
So, after 3 months of easy going things start to fall off the silver shopper.

First to go is the bolt holding the funky derailleur.

What kind of bolt is it, any ideas?

Re: 2 cog derailleur bolt dropped off.
« Reply #1 on: January 15, 2019, 03:24:13 pm »
Dunno off the top of my head - but if you are at school, Balfe's Bikes at 338 Kennington Lane might be able to help you.

From this
https://2.bp.blogspot.com/-_HoS_CVvEUE/U2T7EMabUTI/AAAAAAAA4DA/TDdNaQ9QmIA/s1600/00+Brompton+Part+List+-+Rear+Hub,+Axle+Fittings+&+Chain+Tensioner.jpg

It looks like a standard 10mm (I think) nut + washer.
ETA - if you have hub gears in addition to the two sprockets, it will be different.

Kim

  • Timelord
Re: 2 cog derailleur bolt dropped off.
« Reply #2 on: January 15, 2019, 08:07:25 pm »
My gear hub axle has a weird firkin/furlong/farenheit thread pitch of some sort.  AIUI that is common.
To ride the Windcheetah, first, you must embrace the cantilever...

LittleWheelsandBig

  • Whimsy Rider
Re: 2 cog derailleur bolt dropped off.
« Reply #3 on: January 15, 2019, 08:12:43 pm »
What type of folding bike, leading to what type of rear hub? There are several rear axle thread standards.
Wheel meet again, don't know where, don't know when...

Re: 2 cog derailleur bolt dropped off.
« Reply #4 on: January 15, 2019, 08:18:31 pm »
I *think* the two speed hub is metric and the Sturmey Archer is in black and white.

But I'd probably just buy the appropriate Brompton spare part rather than guess.

Aunt Maud

  • Le Flâneur.
Re: 2 cog derailleur bolt dropped off.
« Reply #5 on: January 15, 2019, 09:41:42 pm »
What type of folding bike, leading to what type of rear hub? There are several rear axle thread standards.

It's a Brompton Supernotlight.

I found a suitable coach screw in the bit box at college, but I'd rather have the proper thing.

LittleWheelsandBig

  • Whimsy Rider
Re: 2 cog derailleur bolt dropped off.
« Reply #6 on: January 17, 2019, 06:53:01 am »
I don't have that hub to hand to check but I vaguely recall the axle has a 10x1 thread (not found confirmation of that) and the third axle nut holds the derailleur in place. What does a coach screw have to do with that nut (or are we talking about a bolt holding parts of the derailleur together)?
Wheel meet again, don't know where, don't know when...

Re: 2 cog derailleur bolt dropped off.
« Reply #7 on: January 17, 2019, 11:55:42 am »
^ I was wondering the same - whether Aunt Maud meant that the two parts of the mech had come apart.

Aunt Maud

  • Le Flâneur.
Re: 2 cog derailleur bolt dropped off.
« Reply #8 on: February 03, 2019, 06:42:43 pm »
It's not anything to do with the hub, but the 2 cog derairlliure type thing which is attached to the folding rear triangle. Currently held on with a bottle cage bolt, as the coach screw decided it didn't like its new job and fell off at Limehouse.