valve stem cracking

[dmar]

I have an 04 fz6 and the front and rear valve stems are cracking at the base..3rd set of tires but not sure if new valve stems were installed..No air leaks at all......Can these be replaced without removing tires from rim...Any input on this would be great...

[F4sSprintST]

Prolly have to pull the tires

Just spray a little soapy water and flex them gently to check for leaks

If no bubbles, I'd just wait for the next rubbers change


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[max384]

You may be able to remove the old valve stem and replace it if you break the bead and crush down the tire. This would probably work well on the rear tire. The front tire may be a bit tougher to do this way though.

[MotoRider]

There is a tool for this job.

Yes the tire needs to be removed (never seen it done without removing the tire).

Might just wait until the next tire change unless it going to be more than a year I would guess.

[kevinwilly]

You've never seen it done without removing the tire because it's not possible, for the record.


Take the time and have metal valve stems put in the next time you have tires put on. I have put them on all my bikes for the last 8 years. I've gone through probably 20 of them. They are like 4 or 5 bucks a piece. I keep about 4 of them in my toolbox at all times just in case I need them.

Bad valve stems is NOT something I like worrying about. They had them on the shelf at a local place called Rural King when I lived in indiana/illinois. Tractor supply also has them, and some auto parts stores do as well.

Pretty sure the brand is Milton (they make all kinds of pneumatic stuff like fittings and filter/regulators and make the valve stems for semi trucks). They come on a red card.

Pretty sure this is it

Amazon.com: Milton S409 Hi Perf Valve: Automotive

Amazon.com: Milton S409 Hi Perf Valve: Automotive

But I'm not 100% sure. I'd have to check the ones I have at home. TOTALLY worth the piece of mind....


EDIT- yeah, that's the one. Can find them for 3 bucks other places. Just search for Milton S409 and you'll find them.

[max384]

Originally Posted by kevinwilly

You've never seen it done without removing the tire because it's not possible, for the record.

How is it not possible? I've done that to car tires before. Bike tires may be a bit stiffer, but it's the same general idea. As long as you can get the tire crushed down far enough to have access to the valve stem, it can be done.

[boner]

Originally Posted by kevinwilly

...Take the time and have metal valve stems put in the next time you have tires put on. ....

they're a few bucks more, but buy 90* stems. they're great.

K&L VALVE STEMS from PARTS411

[dmar]

Now iam paranoid to take a long ride and getting a flat...Does the metal stem extend into the rim or is the rubber base accually sealing the air in..I guess i need a valve stem cross section to find out...

[dmar]

Think i found my answer....Ck out this link on valve stems...Looks like i will be getting another set put on... Maybe do the chain and sprockets at the same time.... Valve stem problem

[kevin_stevens]

Originally Posted by kevinwilly

Take the time and have metal valve stems put in the next time you have tires put on. I have put them on all my bikes for the last 8 years. I've gone through probably 20 of them. They are like 4 or 5 bucks a piece. I keep about 4 of them in my toolbox at all times just in case I need them.

Wait - what do you mean you're "going through" metal valve stems?!? Aren't they pretty much a one-time deal?

Also - I'm not the world's expert on valve stems, but I've been told that there are two different common sizes for Euro-made wheels and Japanese wheels - anyway that there were two sizes and that you needed to know which your wheels used when buying replacements. Maybe someone has more details?

Lastly - I'm not a huge fan of 90* stems because of the mounting design. You have to bolt them into place from the inside of the rim, tightly enough that they will hold against air pressure. This is different than straight valves, which are pressed *into* place by the air pressure. I put a set of 90* stems on a bike myself and had to go through several tire mount/dismounts to get them to stop leaking - and I never really trusted them even after that.

BTW - you want 90* stems? BMW has you covered:



How sweet is that!?!

KeS

[Süsser Tod]

Get them replaced ASAP, when they go, they go with a bang. I had one fail at 125mph, instant flat tire without warning. Since then I've replaced them every time I change the tires, they are ridiculously cheap.

[kevinwilly]

Originally Posted by max384

How is it not possible? I've done that to car tires before. Bike tires may be a bit stiffer, but it's the same general idea. As long as you can get the tire crushed down far enough to have access to the valve stem, it can be done.

I meant that you have to at least break a bead. I think the OP was asking if you can do it without taking the tire off at all... like a complete external removal.

Yeah, if you pop off one side, you might be able to do a rear. You'd be hard pressed to do a front one, though. Maybe with another guy standing on it, I don't know.

Originally Posted by dmar

Now iam paranoid to take a long ride and getting a flat...Does the metal stem extend into the rim or is the rubber base accually sealing the air in..I guess i need a valve stem cross section to find out...

They are metal all the way through with a rummer grommet that seals against the inside of the tire.

Originally Posted by kevin_stevens

Wait - what do you mean you're "going through" metal valve stems?!? Aren't they pretty much a one-time deal?

Also - I'm not the world's expert on valve stems, but I've been told that there are two different common sizes for Euro-made wheels and Japanese wheels - anyway that there were two sizes and that you needed to know which your wheels used when buying replacements. Maybe someone has more details?

Lastly - I'm not a huge fan of 90* stems because of the mounting design. You have to bolt them into place from the inside of the rim, tightly enough that they will hold against air pressure. This is different than straight valves, which are pressed *into* place by the air pressure. I put a set of 90* stems on a bike myself and had to go through several tire mount/dismounts to get them to stop leaking - and I never really trusted them even after that.

BTW - you want 90* stems? BMW has you covered:



How sweet is that!?!

KeS

Yeah, they are a one-time deal. Like I said- I put them on rims whenever I change tires. So when friends have tires put on at my place, I put these in for them and they just give me 10 bucks to cover the cost of them. I've never had one go bad. But I've had about 10 sets of rims personally (between the wife and I) and another 10-15 sets of friends rims that I have put them in. I used to buy the dang stems by the case.

And yes- there are two sizes of holes that are standard. Most motorcycles use the smaller size- european and japanese alike. But the stems I linked to above come with grommets for both sizes, so it'll work on everything.

And 90 degree stems of this type bolt in just the same. You just have to get the right brand. You want the nut on the OUTSIDE, so that air pressure holds them in. I've never had a set leak, and yes I've used them. But they didn't have them locally, so I just used the straight ones most of the time. The ones linked to above with the nut on the inside is a BAD idea. I've had the nut on the outside be a tad loose on my wifes rim once... made a tiny leak- but all you have to do it just tighten it and it's good. if it was on the inside, I'd have had to pull the tire off the rim to get in and fix it. No thanks.

My triumphs and BMW have all come with metal valve stems, though. And the front has always had a 90 degree stem on it for easy access.

Just another reason to buy european.

[boner]

My ducati came with the right angle stems shown with the nut on the inside and I have never had an issue with them. Maybe they’re all gooped up in the inside, I don’t know, I never touch them the I swap tires.

[Süsser Tod]

I've got these, but in black, on my SV:

4 NEW VALVE STEMS and CAPS | eBay

Never leaked.

[max384]

Originally Posted by kevinwilly

I meant that you have to at least break a bead. I think the OP was asking if you can do it without taking the tire off at all... like a complete external removal.

Oh, gotcha. Yeah, in that case, definitely impossible.