Fixed cup will not stay fixed - help!

news said:

Hi

I recently bought an old Benotto, and serviced the bottom bracket. Now the
fixed cup just will not stay fixed, whatever I do. I'd heard old Italian
bikes have this tendency, due to being threaded 'normally', but there surely
must be a way to solve it. Any hints & tips much appreciated.

A thread lock such as Blue loctite?

...d

David Martin said:

news said:

Hi

I recently bought an old Benotto, and serviced the bottom bracket. Now the
fixed cup just will not stay fixed, whatever I do. I'd heard old Italian
bikes have this tendency, due to being threaded 'normally', but there surely
must be a way to solve it. Any hints & tips much appreciated.

A thread lock such as Blue loctite?

..d

You used to be able to buy oversize cups - in the good/bad old days
when everybody had to make everything last for as long as possible.
Were available in 2 sizes for extra oversize. Might be worth asking
your bike shop or phone Spa cycles etc.

cheers
Jacob

news said:

Hi

I recently bought an old Benotto, and serviced the bottom bracket. Now the
fixed cup just will not stay fixed, whatever I do. I'd heard old Italian
bikes have this tendency, due to being threaded 'normally', but there surely
must be a way to solve it. Any hints & tips much appreciated.

A threadless BB, maybe? Your frame might need some machining of the BB
shell to ensure a snug fit, though. The key model that springs to mind
is the Stronglight JP1000 (is it still in production??), though there
are one or two others on the market.

David Belcher

news said:

Hi

I recently bought an old Benotto, and serviced the bottom bracket. Now the
fixed cup just will not stay fixed, whatever I do. I'd heard old Italian
bikes have this tendency, due to being threaded 'normally', but there surely
must be a way to solve it. Any hints & tips much appreciated.

This happened to me early on during a three week cycle-camping tour of Corsica
several years back - it was a hand built Jack Hearne frame.
The cup just kept 'popping' out when under pressure.
It was solved by two leather toestraps wrapped tightly around the bottom
bracket shell.

Moral - always carry a spare toestrap.

Back home I obtained an oversize cup which did the job for several years until
I decided to scrap the frame.

If you haven't any toestraps, you could take it to a framebuilder who should be
able to fill the threads then re cut them.

John B

news said:

Hi

I recently bought an old Benotto, and serviced the bottom bracket. Now the
fixed cup just will not stay fixed, whatever I do. I'd heard old Italian
bikes have this tendency, due to being threaded 'normally', but there surely
must be a way to solve it. Any hints & tips much appreciated.

If it is Italian thread it has to be really tight, as in fixing the cup
in the vice and turning the frame

--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

Many thanks for all suggestions. I shall have a ponder. The more radical
'get a framebuilder to work on it' ideas just sound too costly for me. I
like the idea of the loctite - never heard of it, but it sounds like it
might do the job. If that doesn't work, I might go for araldite! Drastic,
yes, but I can't think when/why I'd ever want to take it off again....

Thanks again all.
"news" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Hi

I recently bought an old Benotto, and serviced the bottom bracket. Now the
fixed cup just will not stay fixed, whatever I do. I'd heard old Italian
bikes have this tendency, due to being threaded 'normally', but there

surely

Quoted message said:

must be a way to solve it. Any hints & tips much appreciated.

news said:

Many thanks for all suggestions. I shall have a ponder. The more
radical 'get a framebuilder to work on it' ideas just sound too
costly for me. I like the idea of the loctite - never heard of it,
but it sounds like it might do the job. If that doesn't work, I might
go for araldite! Drastic, yes, but I can't think when/why I'd ever
want to take it off again....

The "permanent" (red) version of Loctite Threadlocker (from motor
accessory shops) might work even better than Araldite, though I would try
the medium (blue) first. It bungs up the threads and is less brittle than
Araldite.

Degrease the shell and cup then apply plenty of Loctite to both the shell
and cup threads. Tighten cup as much as possible. Leave to set for at
least 24 hours.

PTFE tape is another option, though I don't think as good as Loctite.

~PB

Pete Biggs said:

PTFE tape is another option, though I don't think as good as Loctite.

PTFE is used as a dry lubricant. Surely not the thing you want in these
circumstances? I would have thought Loctite has got to be worth a try.

Tim

Quoted message said:

~PB

Tim Downie said:

Quoted message said:

PTFE tape is another option, though I don't think as good as Loctite.

PTFE is used as a dry lubricant. Surely not the thing you want in
these circumstances?

PTFE tape (plumbers tape) hasn't worked well for me but I mention it
because it is a common solution and apparently has worked for others.
Putting some material in between the cup and shell does make the cup a
tighter fit, regardless of how comparatively slippery the tape might be.
In fact it feels a bit rubbery to touch, not terribly slippery.

The main problem I had was the tape being disintegrated by the sharp
threads.

~PB

In article <[email hidden]>

news said:

Many thanks for all suggestions. I shall have a ponder. The more radical
'get a framebuilder to work on it' ideas just sound too costly for me. I
like the idea of the loctite - never heard of it, but it sounds like it
might do the job. If that doesn't work, I might go for araldite! Drastic,
yes, but I can't think when/why I'd ever want to take it off again....

The fixed cup on my old Holdsworth tourer was held in with Araldite for
years before I got it sleeved by Argos. Note that the various bodges
work much better with a cartridge BB than with cup & cone types, because
the side thrust on CCB bearings is considerable.

In article <[email hidden]>, Pete Biggs

() said:

The "permanent" (red) version of Loctite Threadlocker (from motor
accessory shops) might work even better than Araldite, though I would try
the medium (blue) first. It bungs up the threads and is less brittle than
Araldite.

Super-duper Loctite is what holds Windcheetahs together, so /ought/ to
be the trick.

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
I am Wan, for I am pursued by the Army of Plums.

Dave Larrington said:

In article <[email hidden]>, Pete Biggs

() said:

The "permanent" (red) version of Loctite Threadlocker (from motor
accessory shops) might work even better than Araldite, though I would try
the medium (blue) first. It bungs up the threads and is less brittle than
Araldite.

Super-duper Loctite is what holds Windcheetahs together, so /ought/ to
be the trick.

Does it have a dark side and a light side or am I mixing it up with
The Force again?

Tim

In article <[email hidden]>, Tim Hall

() said:

Dave Larrington said:

In article <[email hidden]>, Pete Biggs

() said:

The "permanent" (red) version of Loctite Threadlocker (from motor
accessory shops) might work even better than Araldite, though I would try
the medium (blue) first. It bungs up the threads and is less brittle than
Araldite.

Super-duper Loctite is what holds Windcheetahs together, so /ought/ to
be the trick.

Does it have a dark side and a light side or am I mixing it up with
The Force again?

That's gaffer tape...

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
There's a village in Texas that's missing its idiot.