As per the topic, my rims have holes for schrader valves, can i use a presta tube in the hole or do i need to put something in to fill out the hole?
Reason being i am the only person in the group i ride with Schraders so if im unlucky enough to pinch flat two tubes im stuffed as everyone carries prestas.
You should be fine as long as there's nothing spikey to catch on the tube or valve stem.
Mavic rims have gromits to make the holes smaller.
Don't you carry patches?!
Should be fine short-term, providing the valve hole is fairly smooth and you're not sticking loads of air in them. I think one of my old bikes had 'down-sizing' thing in the rims, so they might be available from CRC or your local bike shop.
Yeah, I do it all the time, just make sure that you screw the lock ring down nice and tight to stop it all slipping about
As others have said you need some of them valve hole reducers like this:
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I think one of my old bikes had 'down-sizing' thing in the rims, so they might be available from CRC or your local bike shop.
http://www.sjscycles.co.uk/product.asp?pf_id=3335&src=froogle
You can get aluminium grommets too; I picked one up from my LBS when I bought my new bike - mine has Presta, OH's bike is Shraeder, I figured it was less weight / bulk to carry a spare Presta tube and adapter on rides out than two tubes.
They will be fine, you don't [b]need[/b] anything, but you would be better off getting some just in case you snap the valve.
I have been drilling all my rims for Shraeder since I can remember and use Presta as a preference- Never used those grommet things and never had valve problems.
Is it Continential tubes that have a stepped lock ring? When screwed onto a prestra valve in a schrader rim, they locate nicely in the hole.
Cheers for the all the replies. I'll grab some of those grommits from the LBS next time im in.
Don't you carry patches?!
I do but if its pinch flats your going to limp home with a patch especially if you double side it.
Did whites level on Sunday and at the bottom of the black run was like a grave yard for inner tubes. While we were there fixing a flat we saw 1 in 4 picking up punctures.
[i]"Is it Continential tubes that have a stepped lock ring?"[/i]
I've got some of those stepped lock rings. I think mine came with Schwalbe tubes.
I've never had a problem but wouldn't tighten up the ring. It is normal practice on a trials motorcycle (where tyre creep can occur) to throw the ring away and elongate the hole so that when the tube moves the valve does not get ripped out. This is quite transferrable to a mountainbike, though I wouldn't alter the hole in that case.
Is it Continential tubes that have a stepped lock ring?
schwalbe tubes come with them as well
yes. MIghty tricky to use a Schrader valve on a presta rim though.