Slipping Rear Axel

[DubDuck]

I've recently picked up a '99 FSR DH. After a few blocks on the first ride I heard a rubbing/Grinding sound and stopped to investigate. I noticed the tire rubbing on the swing arm and the disk grinding on a nut.
I was able to tighten the quick release tighter and it seemed to work until I hit a few rocky trails the next day. I tighened it as much as I could and it was fine for awhile.
It's getting worse; now when I really stand on the pedals and send some torque to the rear wheel it seems to pull the axel slightly loose. Loose enough to rub the brake pads.
Will buying a new axel solve this problem? The hash marks on the axel nut that mate to the frame appear filed down.
It was killing me today on a long ride. I was having to stop every 1/2 to 1 mile to adjust the rear axel again.
By what you can see in the picture; does it look like the frame it's self is worn and causing the axel slipage?
Any suggestions?

 

[cce]

get a shimano QR on there and you should be fine.

 

[We_are_Stevo]

The axle is fractionally too long as it is so the dropouts aren't nipping up tight enough to hold it securely; you need another thin washer or two in there so that there is fractionally less axle in the drop out then you'll be okay

 

[Raging_Bulls]

Looks to me like the QR nut is worn, causing it to slide under pressure. The "wear" on the frame itself is merely the result of the QR nut sliding around.
Getting a new Shimano QR should solve it.

I have a similar problem with a set of (brand-new KCNC) titanium QRs, which just don't hold the wheels in place when accellerating or braking hard. As soon as I put my trusty XT ones back in, the problem vanished.

 

[Anthony]

I think we are stevo may be right. I would check whether the axle is precisely centred on the hub. If there is more axle protruding from the hub on the drive side than on the other side, that would be expected to cause this problem. The end of the axle has to be inboard from the surface of the dropout even under compression, otherwise the skewer can't do its job.

You may be able to solve the problem with some washers, but if the axle isn't centred, the fundamental solution is to centre it.

Although it's true, as others have said, that the nut and the dropout are worn, this may just be part of the symptoms rather than the root cause.

 

[silverclaws]

Looks like a lot of wear in there to me, but that might just be wear caused by the slippage which is getting worse all the time.

Now the axle, yes, I would be inclined to agree it is a tadge too long in that drop out, but something to check perhaps, how much axle is available for riding in the drop outs on either side before the QR is tightened. I say this because recently I discovered on my back wheel there was more on one side than the other, meaning that with the QR tightened, one side of the axle was nice and tight and the other not so much. How I found it, was I was having bearing problems on the cassette side, so a bit of trial and error and the axle is now correct, bearings happy, everything in line and centred and no problems.

Oh and yeah, a steel frame and steel QR, so no wear and no slippage, the bearings got it instead and one cone had to be replaced. Aluminum alloy to me is a place I won't go due to it's ease of destruction.

Now it could be someone has had the axle out and upset the position of the 'stay put' cone, the one on the cassette side due to it's unease of adjustment. It is very surprising how a few degrees of thread turn can change the position of that cone.

Alternatively putting washers to drop in the crap out on the trail is another way of increasing the clamping power of the QR, but there is nothing like getting the situation correct in the first place as to me adding stuff to take up problems is the slippery road down hill, yeah it does and should only really do as a temporary measure until one has the time to get it right.

 

[Rampage]

Is the nut hitting the bolts that holds the mech hanger on and not tightening fully?

 

[We_are_Stevo]

...you can see in the photo' that the end of the axle is all shiny where it has been fouling the quick release; turn the bike upside down, nip up the quick release and note the position of the ends of the axle in the dropouts.

If, as suggested above, the axle isn't centred (more axle in one dropout than the other) adjust as necessary. If it is centred add a washer either side (behind the final nut) and it will stay tight

 

[unkleGsif]

Is no one else noticing that there is no sign of damage to the inner surface of the QR nut? Surely if the axel was fouling and therefore preventing the QR from tightening, then there would be damage to the inner, recessed surface of the nut... Also, due to the depth of the QR nut, the ax would have to stick out a hall of a long way!

My money's on just the damaged QR

G

 

[Rampage]

Could it be at the other end?