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Help - Tire mounting problem….(5 posts)

Help - Tire mounting problem….TFerguson
Feb 14, 2003 11:19 AM
I built a set of wheels for a friend using Ambrosia Balance rims ( marked 622 - 13) and am having a very, very difficult time getting the tires on the rims. I started with Mich Bi-sports and, thinking it was the tires, pulled the Axial Pros off of my OPs and tried them. Almost impossible. In fact, I would probably have to walk home if I had a flat on a cool day.

Anybody had any experience with this problem? Do some brands of tire have a larger inside circumference than others? Any suggestions?

re: Help - Tire mounting problem….jw25
Feb 14, 2003 1:56 PM
Well, as you've discovered, some rims run bigger than others, and some tires run smaller. I haven't seen a Balance in person, but they should be close to the OP dimensionally.
So let's start troubleshooting. What kind of rim tape did you use? I love Velox, since it's so easy and lasts forever, but on skinny road rims, I've been using 2 layers of 3M fiberglass strapping tape (12mm). It covers the spoke holes, and I've had it up to 140 psi on some aero rims, with no problams so far. It's thin enough that the beads get more room to settle when installing the tire, and might help get them on.
Michelin's beads tend to run small, and they use larger-diameter bead material than some other tire companies. I've had to "premount" a few tires, where you install it without a tube, just to stretch the bead a bit. On some rims, I need to use a lever to snap the final piece of bead in, no matter what. Just watch the tube, and make sure everything's seated before inflating.
On the other hand, I have some Open Corsa CX's that are so loose I could mount them one-handed, and actually need to hold them in place while mounting, so the section inside the rim doesn't slide back out. Once inflated, everything's golden, of course.
So, try stretching the beads a bit - I've even stood in a new tire and used my feet and hands to stretch them. I was pretty frustrated, see, and it worked. Soapy water is also good. And if that doesn't work, spend a few bucks on thinner rim tape.
Are all Vittorias larger?….TFerguson
Feb 15, 2003 5:12 AM
Are all Vittorias larger? Or just the Open CX types? Or just that particular batch?

Your right in that the outside circumference of the rim is the same, but the inner wall on the OPs allows the bead to drop in farther during installation. I may try the fiber tape.

The Bi-Sports are still so tight the fourth time I've mounted them that I had to use levers. I didn't pinch the tube this time, but.

Thanks for your reply,
Feb 14, 2003 5:07 PM
get some silicone spray and spray it on the side of the rim you are tring to mount the tire on.
the tire will slip right on.
once you have mounted the tire pump it up
as you know the rim is a very important part of the
braking system and if there is silcone spray on the
rim when you go to stop, get the picture!
I have noticed that some silcone on the tire helps too
and silicone wont harm the tires either
Windex (nm)Spoke Wrench
Feb 15, 2003 7:28 AM