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Question about tube valve stems

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This might seem pretty simple but I am a little confused on something and I cant find a good answer in my service manual. Where the tube valve stem sticks up through the rim, is there a nut on the exposed side of the rim or one inside where the tube is? My front wheel has a nut on the outside and is missing the rubber gasket thingy over the stem and my rear wheel has the rubber gasket thingy without a nut. Im confused.

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I think most new tubes come with 2 nuts and a sort of conical washer. It depends on the application as to what of those parts you use.

I always keep the conical washer on the stem, between the tube and inside of the rim.

As for the nuts, different people have different ideas on their installation.

"I" don't put a nut on the stem outside the rim, tightening the stem to the rim. On the rear especially, you risk ripping the stem out of the tube, should the tire slip on the rim with hard acceleration or stopping. Letting the stem float in the hole allows it to cock to one side should the tire slip on the rim.

The rubber "gasket thingy" goes over the stem without a nut underneath. Helps seal the stem hole.

IMO, your rear is correct. Keeping a nut on the front is up to you. You can also rip the stem out of the front too with hard enough braking, depending on what you run your tire pressures at and whether or not you have a rim lock.

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Nut

The nut is to keep the tube stem out when you are inflating the tire. Otherwise, you could push the stem back into the rim. I was told by some some very good enduro riders to put the nut half way down the stem, fill the tire, put the valve stem cap on, then back off the nut until it is locking on the valve cap. This lets the stem get sucked far into the rim before stopping on the nut, which at that point, it will probably rip off the stem. Now, you need a new tube. The reason to leave the nut at the top is so it is there if you need it for filling the tire.

Rubber valve stem grommet (?)

This is to keep mud from getting inside the rim. Actually, the rubber valve stem grommet can be used to hold up the valve stem while filling. They are nice to have and look nice. A piece of duct tape works if you lost one.

Valve caps

I have one that can be used to remove valve cores, the other is a standard plastic cap.

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This what I do too.

Nut

The nut is to keep the tube stem out when you are inflating the tire. Otherwise, you could push the stem back into the rim. I was told by some some very good enduro riders to put the nut half way down the stem, fill the tire, put the valve stem cap on, then back off the nut until it is locking on the valve cap.

Valve caps

I have one that can be used to remove valve cores, the other is a standard plastic cap.

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What if the stem has been cocked to the side quite a bit, is there an easy way to adjust the tube so that the stem is straight again?

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That's one good thing about leaving the stem loose in the rim. It is a visual indication of the tire slipping on the rim.

To straighten it you have to deflate the tire and break the bead and work the tire around on the rim a little to straighten it. Then re-inflate.

What if the stem has been cocked to the side quite a bit, is there an easy way to adjust the tube so that the stem is straight again?

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Thanks Guys I always tightened the nuts and yes ripped a few valve stems off. Going out to take the nuts off.

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I dont think you should completely remove the nuts. Just loosen them to the bottom of the air cap like creeky said so you can still get air in them and they can still shift some.

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I agree. That nut comes in handy should you need to change/patch a tube out on the trail. Once you get the stem inserted in the hole, you can start the nut on it and it prevents you from inadvertently pulling it out again while mounting the tube/tire to the rim.

I dont think you should completely remove the nuts. Just loosen them to the bottom of the air cap like creeky said so you can still get air in them and they can still shift some.

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