Inner Tube Valve Nut
 

I have heard it said that the nut on the valve stem of the inner tube that sits against the wheel rim is actually just for aiding the fitting of the tube and should be backed of completely up to the valve cap (to stop it rattling and help lock on the valve cap). This is supposed to let the tube move a little off road and help avoid stressing the tube around the valve seat.

Can anyone confirm if this is so and also if it really makes any difference. I can actually see the theory making sense but this is the first I have heard of it and I have certainly never done it before.

I am not going to loose sleep about it but am interested to hear peoples opinions.

Thanks all.

that is true.. on all my previous "proper" dirtbikes, we would actually remove the nut altogether.. however, these bikes ran rimlocks which helped the tyre spin the tube..

I'd say that if you are lowering your tyre pressures while offroad, it's a good idea to loosen the nuts.. but also in saying that, these aren't exactly firebreathing, tyre spinning power houses either ;-)

On dirt bikes i normaly do the nut up finger tight ,then undo it about 3-4 turns ,that way if the tyre does spin you will notice the valve at an angle so you can sort it before it rips the valve out

I agree with warnerbrother, the idea is: to give you time to notice that you are getting a flat before your valve stem gets ripped out of the tube and this will happen quicker if you dont have rim locks.
Back that nut up to the valve cap.

cheers.
Reg

Cheers guys. Job done.

Something like this: dust cap(MX style) combined with nut screwed up to the valve cap(as advised by the mechanic in the shop). Greetz, Hans.
http://dallastx.smugmug.com/Motorcyc...1_BxD84-XL.jpg