Bike feeling unstab...
 

[Closed] Bike feeling unstable on back wheel

 Creg
Posts: 1364
Free Member
Topic starter
 

Ive been riding to and from work every day this week. The bike has been making its usual creaks and squeaks as Ive been riding it, but as the week has gone on Ive got one problem that has been getting worse.

The bike has started to feel very unstable on the back wheel. When riding round corners (while pedalling) the bike has become quite loose and Ive nearly binned it a few times, with the back end sliding right out and slipping. When riding in a straight line it feels like the back end is pushing slightly out to one side. At first it was only when I made harsh turns but now its doing it with slight movements

I know the wheels could do with a little truing so would this solve the problem or is it something else?

The rear tire has a good amount of air in it and feels quite firm (although it does squash out a bit when I get my fat arse in the saddle)


 
Posted : 05/07/2009 6:50 pm
Posts: 5941
Full Member
 

What bike is it ?

FS or HT ?


 
Posted : 05/07/2009 6:51 pm
Posts: 656
Free Member
 

Check that the QR is done up properly, and not damaged.

Check that the rear axle isn't broken or cracked.

Check that there is some tension in the spokes.

Check that the back of the frame isn't cracked.

Had that feeling in the back of my bike a few times, and it's been one of the above. Otherwise, your tyre might just be knackered.


 
Posted : 05/07/2009 6:57 pm
 Creg
Posts: 1364
Free Member
Topic starter
 

Its a FS.

Ive checked the QR as that was my first thought but its done up nice and tight.

Ill check the spokes as Ive had an issue with the rear mech throwing the chain off the cassette so it might have damaged some spokes.


 
Posted : 05/07/2009 7:06 pm
Posts: 6886
Full Member
 

I'd strip the hub down, could be cones working loose as well.


 
Posted : 05/07/2009 7:17 pm
 dobo
Posts: 3
Free Member
 

low psi tyre squirm on the rear is horrible, had it today with a slow puncture, it could be that, 30 psi will feel fairly hard for a lightweight but a large bloke will make it squirm all over the place


 
Posted : 05/07/2009 7:32 pm
Posts: 5941
Full Member
 

Suspension bearing or shock bush.

When my bushings were on the way out, the back end felt all "wobbly" when cornering hard.


 
Posted : 05/07/2009 7:37 pm
Posts: 0
Free Member
 

or you might just need to tighten up the lock ring on the cassette?


 
Posted : 05/07/2009 8:00 pm
 Creg
Posts: 1364
Free Member
Topic starter
 

bastard bastard bastard bastard

frame is cracked on the swinging arm

shit


 
Posted : 06/07/2009 11:07 pm
Posts: 25921
Full Member
 

unlucky, but at least you've not been dumped under a lorry by it


 
Posted : 06/07/2009 11:11 pm
Posts: 621
Free Member
 

pics?


 
Posted : 06/07/2009 11:15 pm
 Creg
Posts: 1364
Free Member
Topic starter
 

Ill get some tomorrow.

The crack is on the chainstay where there is what appears to be a crossbar just behind the seat tube. The crack runs right through from the top to this cross bar and is the width of the whole chainstay...crap description I know.


 
Posted : 06/07/2009 11:26 pm
Posts: 0
Free Member
 

What make of frame?


 
Posted : 06/07/2009 11:31 pm
 Creg
Posts: 1364
Free Member
Topic starter
 

Trek Fuel. 2005 I think


 
Posted : 06/07/2009 11:33 pm
Posts: 41395
Free Member
 

Commencal.


 
Posted : 06/07/2009 11:34 pm
 Creg
Posts: 1364
Free Member
Topic starter
 

[IMG] [/IMG]

Photos for those that are interested


 
Posted : 08/07/2009 7:02 pm