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soup[_7_] soup[_7_] is offline
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Default Towbar mounted bike rack problem

On 05/06/2021 09:59, soup wrote:
On 04/06/2021 21:01, Murmansk wrote:
I have a Witter bike rack that attaches to the towbar.

You put it on and at first its all loose and of course will lift off,
then you tighten a big bolt which at first is really easy as it goes
round for quite a few turns without much resistance, then as it grips
the towball you give it a couple of really firm turns with the spanner
to make it fully grip the ball.

Removing the rack is the reverse of the above where youÂ* apply big
force for a couple of turns to loosen it, then lots of relatively easy
turns to make it loose enough to actually come off the towball.

The problem is that once Ive loosened it enough to make the rack sag
but not actually come off, the bolt starts to feel really tight again
€“ almost as tight as it normally does at the last stage of attaching
it €“ so much so that I feel as though I need to apply so much force as
to damage the thing.

Im now left with the bike rack attached and sagging but cant remove
it and Im wondering if anyone has any experience of this?

Â* Sounds very like a bolt with a damaged thread (possibly a bent bolt).
Can it be economically replaced?
Alternatively you could take it all the way out and 'hand chase' the
threads. This may involve mounting in a lathe (local light engineering
firm for the cost of a couple of pints) and running a chase along it.

Just realised you 'say' you can't move it out at all. Maybe try oiling
and working the bolt in and out eventually freeing it (be prepared to
cobble up a hole new looking system as if the bolt is harder than the
threaded part it may well cut its own thread thus knackering any holding
function).




Whole not hole.
Locking not looking

Note to self :- Think, have you said everything and proofread before
clicking 'send'.

Use a chaser NOT a die to clean the thread (looks and operates rather
like a die but doesn't cut so much as 'clean'.

You can use a hand chaser (rather like a file with a thread pattern on
the tip) That way you only ,really. have to concern yourself with the
thread profile not, within reason, the actual diameter