Trouble pumping Shamal 2-Way Fit

[scottaharper]

I am having a hard time pumping up the rear tire on a new pair of Campagnolo Shamal 2-Way fit wheels with tubeless tires. This is my first experience with tubeless, so maybe I am doing something wrong. After a bit of sweating, I was able to mount the Fusion 3 tires on the rims, and pump up the front wheel. It appears to be holding air fine without any sealant. My problem is the rear wheel. I was able to get the tire partially pumped up, but when I get about 50 psi in the tire, air starts leaking from the pump head because the Campy valve does not stick out very far from the rim. I suspect this is because the rims are deeper in the rear and the valves are the same length. So, I have enough valve stem for the pump to grip in the front, but not in the rear.

I tried two pumps, and have had the same results with both. Admittedly, one pump has a Topeak Smarthead that is probably at the end of its lifespan, and the other pump has a cheap Cutter model with a head with separate holes for schrader and presta, but I have not had this problem on other wheels that I have used these pumps for.

Has anyone else experienced this?

Should I invest in a better/newer head for my pump or a new pump? If so, do you have any recommendation for a pump/head that will grip short valves?

Should I get another valve assembly with a longer valve? Any particular recommendation?

Thanks,
Scott Harper

[MattTuck]

Try doing it with sealant? and CO2?

My, admittedly novice, understanding of tubeless is that seating the rim and bead is very critical. I thought (could be wrong) that you did this most effectively with a high pressure burst of air, such as a CO2 cartridge or a compressor.

I can understand not wanting to fill the tire with lots of sealant, but I think for the bead, it might not be bad?

[scottaharper]

I do not think the bead is the problem. The bead is seating and the tire pumps up to 50 psi and holds air. The problem is that the pump head is not sealing well enough to attach to the limited valve stem that is exposed to go beyond 50 psi. At least that is what I think.

Scott

[alioup]

Try using one of these?
http://www.coloradocyclist.com/img/product/full/i/innppz43.jpg

[onetwentyeight]

Even with a compressor, campy wheels and hutchinson tubeless tires are a total nightmare. I try to talk my customers out of even trying.The only advice I have is don't use a tire lever to get them on, no matter how much you want to, it can deform the bead enough that they won't seat. Also check the area around the valve and make sure the tire is seated there properly and not ontop of the rubber bit on the backside.

Re-reading your post, a different pump head might not be a bad idea. I love my Silca + Hirame combo, but I believe Hirame heads are no longer imported by anyone to the US.

(Imho, tubeless is over rated, and while promising, not yet ready for primetime. I'd rather use a high quality clincher, or a tubular with a canister of Vittoria Pit Stop in my saddle bag)

[jds108]

If the problem is that the stem is too short, get a longer stem.

[monkeybanana86]

I have a valve extender that screws on to the valve but be warned that they leak. Still works even though not well. I'd give it to you but I just realized that my back up wheel is a shamal :(

http://www.topeak.com/products/Pumps/PrestaValveExtender

Luckily a shop had it and it was only 6.99

[AngryScientist]

If the problem is that the stem is too short, get a longer stem.

ding ding ding.

they make tubeless valves in multiple stem lengths.

also, the lezyne head screws right on, and will work with even the shortest stems...

[oldpotatoe]

I am having a hard time pumping up the rear tire on a new pair of Campagnolo Shamal 2-Way fit wheels with tubeless tires. This is my first experience with tubeless, so maybe I am doing something wrong. After a bit of sweating, I was able to mount the Fusion 3 tires on the rims, and pump up the front wheel. It appears to be holding air fine without any sealant. My problem is the rear wheel. I was able to get the tire partially pumped up, but when I get about 50 psi in the tire, air starts leaking from the pump head because the Campy valve does not stick out very far from the rim. I suspect this is because the rims are deeper in the rear and the valves are the same length. So, I have enough valve stem for the pump to grip in the front, but not in the rear.

I tried two pumps, and have had the same results with both. Admittedly, one pump has a Topeak Smarthead that is probably at the end of its lifespan, and the other pump has a cheap Cutter model with a head with separate holes for schrader and presta, but I have not had this problem on other wheels that I have used these pumps for.

Has anyone else experienced this?

Should I invest in a better/newer head for my pump or a new pump? If so, do you have any recommendation for a pump/head that will grip short valves?

Should I get another valve assembly with a longer valve? Any particular recommendation?

Thanks,
Scott Harper

2 suggestions..

Compressor and sealant. Both will help seat the tire.

[oldpotatoe]

Even with a compressor, campy wheels and hutchinson tubeless tires are a total nightmare. I try to talk my customers out of even trying.The only advice I have is don't use a tire lever to get them on, no matter how much you want to, it can deform the bead enough that they won't seat. Also check the area around the valve and make sure the tire is seated there properly and not ontop of the rubber bit on the backside.

Re-reading your post, a different pump head might not be a bad idea. I love my Silca + Hirame combo, but I believe Hirame heads are no longer imported by anyone to the US.

(Imho, tubeless is over rated, and while promising, not yet ready for primetime. I'd rather use a high quality clincher, or a tubular with a canister of Vittoria Pit Stop in my saddle bag)

But, but, but, what about what the marketeers say about road tubeless??

I agree, after over a decade of bicycle tubeless, still only one real tire maker, few models, limited/no advantage for that enthusiast's bicycle.

High end clinchers, some Stan's in the tubes, or the best, tubular with sealant....

[crownjewelwl]

taking off the valve stem and dipping it in sealant then put it back in. i never had a problem with the length.

i used to run the same combination.

wait til you get a flat that the sealant won't fix on the road!!