rear wheel jump??

[law]

Hiya can anyone help?
I've got an old giant MTB in my cellar and decided it was time to get off the roads and try a bit of MTB riding over in Delamere forest.
As the old 26" rear wheel I had on the bike was so badly buckled I tried putting some 26" wheels on it that my friend gave me which were off a different bike.

Very straight forward I thought, however I took it for a test ride round the block and the rear wheel jumped out of the frame and rammed it's self into the seat post on about 6 occasions.
As far as I can tell the problem is that the new rear wheel is a quick release, and the old wheel was an old nut and bolt style wheel.

Am I right in thinking that the QR's just haven't got enough grip to hold the wheel in?
They didn't really look like they had enough space to grip in the dropouts either.

JUst hoping someone can clarify.
Thanks.

Tom.

 

[Blindside]

Hi mate
Is the old wheel 7 or 8 speed? and the new one? Could possibly be a rear hub spacing issue between the new and old wheel

 

[My_Teenage_Self]

Have you tried tightening the nut on the other end of the QR before closing the lever?

 

[law]

Both wheels are 6 speed, and the spacing's the same too.
I tightened the bejesus out of the qr skewers once I'd skidded across the road a couple of times. Still made no difference.

 

[ishaw]

I built a bike for a friend and used some old alloy qrs, but we soon found that under load we would end up pulling the wheel over to the chain stay. A quick inspection of the qrs told me all I needed to know, the knurled 'grip' had worn flat so was not up to the task of gripping the frame. Fitted some old faithful steel shimano qrs and problem solved.

 

[Raging_Bulls]

I second that. The QR's profile has probably worn off. Try a new(er) QR.

 

[law]

Thanks everyone.
They're the cheapo aluminium qrs.
I'll try some steel ones instead.
Cheers.