First year on tubulars and so the Grifos are my first tubular tires. One thing I noticed is that the air leaks out of the pretty fast - after a day or two they will drop from 30-35psi to 20. Is this normal or do I have leaky valve stems - both tires have extenders on them.

If this is normal for the tires - I guess I could throw some latex mixture in them to help seal them a bit.

Michael
www.MLKimages.com

this is common with Grifos and nothing to worry about.. They are great tires...

They drop pressure because they use a latex tube instead of a buytl tube.

The latex tubes are lighter and they are thinner, so the air molecules can escape easier through them than the rubber buytl tubes.

You could remove the valves and put in some Stans to help slow it down.

All quality road tubulars have latex tubes in them.

Hey,
i just got a pair as well, can some one help a rookie with mounting direction? Is it like other tires, arrows point forward in front and the opposite in bac? should i be sealing them?

I mount 'em front and rear the same. Others do the rear backwards. I have no problems w/ traction. Mine leak, too. I left them be for a whiole but my front developed a faster leak, so I Stan'd them up and no worries now.....

How are you all getting sealant in the Grifos? As I understand it, the Grifos don't have removable stems, so how's it done?

How are you all getting sealant in the Grifos? As I understand it, the Grifos don't have removable stems, so how's it done?They have removable valve cores.

They have removable valve cores.

I know I am showing my newbism, but um, how do you remove the cores? Thanks!

They have removable valve cores.

I've got two sets of Challenges. Though I haven't inspected them closely, I think that at least one of the pairs doesn't have removable cores. Both sets are the new tread pattern.

I've got two sets of Challenges. Though I haven't inspected them closely, I think that at least one of the pairs doesn't have removable cores. Both sets are the new tread pattern.On the set I have, each seems to have a different inner tube. Fortunately, they are both removable. . .

I know I am showing my newbism, but um, how do you remove the cores? Thanks!If you inspect the threads that the plastic valve cap screws onto, you should see that their are wrench flats machined into them. You can use these to unscrew the core.

It sounds like they use a mixed bag of tubes, so it is possible that one or more of the tires you have don't have the removable core. Usually a removable core will be silver where as the valve stem is bronze colored.

If there is no core, you can use a large bore (veterinary) syringe to inject the sealent through the tire into the tube. This will puncture the tube, but the sealent will fix it.

I have two pair of the new grifos. I use stans in them as a preventative measure, about 1/2 - 2/3 of a scoop each. They all have removeable valve cores. I still get the same air loss you describe. That is normal, I think. They hold air fine for the races, which is all I use them for.