Bottom bracket loose on muddyfox mtb.

[fenlandpsychocyclist]

Ok, i know its classed as a "cheap" mountain bike, but my brothers muddyfox bullit has
strange bottom bracket issues.
Basically two days after he bought it the bottom bracket axle started working loose.

I used my shimano tools to undo the lockring, adjust the centre leaving a teensy bit
of play, and then retighten with a drop of locktight on the thread for good measure.

Today its gaining play again, but the fixed and adjustable threaded caps have not started
creeping round (i marked the positions of them).

I think its a cartridge type insert ... can anyone look this mtb up?
Any ideas. Maybe its his 19 stone bulk standing on the pedals in top gear?

 

[simon.r]

This doesn't answer your question, but for the sake of £10 I'd be tempted to throw the BB away and replace it with something like this* IME very cheap BBs just aren't worth trying to fix. I think the main problem is that the bearings are so cheap and nasty that they just don't work properly, no matter how well greased and adjusted they are.

*Assuming it's square taper and the shell / axle lengths are right.

 

[cyberknight]

Take it back as this sounds like the bike has been sold without being put together right , no bottom bracket however cheap should work loose after 2 days .
Give the seller the choice of a refund, a new bike or them paying for the cost of a bike shop fixing it.
If it was bought via a website the same deal applies, your contract is with the company who sold it to you and not the maker of the bike so do not let them fob you off.
http://whatconsumer.co.uk/it-is-not-fit-for-purpose/

 

[fenlandpsychocyclist]

Thanks for the advice guys.

I've nipped it up again, and the heavyweight rider has been out on a 15 miler today ... without any change
in freeplay so maybe its finally settled in!

If it gives any more problem he'll be going back to tescos direct for a refund.
(I told him he'd need to spend at least £350 to get anything decent nowadays)!

 

[mcshroom]

Well £229 anyway - link

I had a bottom bracket that kept working loose. I solved it by replacing the grease on the BB shell with PTFE tape.