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Tires out of round


By midgey - Posted on 24 February 2013

NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.

With out sounding like a total newbie here, I'm hoping someone might be able to throw me a bone on a recent issue.

I have a giant 29er fitted with the standard schwalbe nobby nics that came with the bike.
Today I went to rotate the tires front to rear, and once inflated both are incredibly out of round, and seem off centre of the rim.

I deflated and re-inflated them and tried to manipulate the way they sit on the rims but without much luck.

I've changed tires a million times without issue, however this is the first time on the 29er.

Am I missing something?

Any help would be appreciated!

Thanks...

i would take it into a shop, see if they can look at it free. if not maybe somebody can tell you whats wrong with it.

Is it just a case of the tyres not sat in rims properly?

Try pumping the tyres up to 40ish PSI and see if they pop into place, then let the excess air out to your normal pressure.

Deflate the tyres,
Rub a soapy/ bubbly water mix around the rim edge/sidewall of the tyre and pump to about 45psi. If the tyre doesn't seat properly after that then something's wrong.

Pete, I'm pretty sure it is just the tyre off centre, but as I mentioned I tried deflating and adjusting without luck.

Gazza, the soapy water sounds simple, but genius - I'll try it during the week.

Thanks!

Is the high point around the valve area? might be as simple as needing to deflate a little and push the tube in so the bead can seat in the groove properly. The thick section that supports the valve often gets in the way.

Hi Midgey, agree with comments above, I have a 29er and fixed a puncture a few months back. Upon re inflating could not get to seat properly and tyre was out of balance. Was running tubes but did have tubeless rim strips in which made seating harder. Long at short, pumped to about 70psi, rolled bike around in garage and "pop" tyre went into place perfectly.

I have the tubeless rim strips too.

I will try similar, however I'm keen to try a bit of soapy water too.

Hawkeye, its not at the point where the valve is situated...

Hokay, then just carefully up the pressure with a track pump until you hear it go POONG! when the bead seats. Laughing out loud

Well, that's what mine sound like Sticking out tongue

Just keep an eye on it so that you don't have the bead gapping the rim and showing exposed tube - that will go BANG instead of POONG... not good Eye-wink

If you have Carbon MTB rims do NOT inflate above their rating (some as low as 40 psi)- else you may collapse the rim.

Check the line on the tyre that is just above the bead, if it isnt even distance from the rim all way round then it isn't seated properly.
If you have tubeless rim strips in and using a tube - get rid of the rim strips and maybe use a standard rim strip or tape. If you have a non tubeless tyre the rim strip will jam under the bead and not let the tyre seat properly - expecially on Giant rims.

If tubeless try the soap trick BUT sometimes this wont work - you can also try WD40 around the rim, the WD40 will let the tyre slide easier, then it dries out. Has no effect on tyre rubber. works omn tubed and tubeless

If tyre not caught up on rim strip or valve and wont seat at 45PSI (assuming this is below the rims limit) then lay wheel down so tyre is flat on a solid surface, you can hit tyre with rubber mallet at the points where the tyre bead has not seated properly which can jolt it to seat properly.

But get rid of the tubeles rim strip if you not going tubeless.

HTH

I recently dismantled & cleaned both tires. The main purpose was to clean & scrub out the old 'Stans' thoroughly.

The secondary purpose was to take the rear wheel into the LBS to have it balanced. (Note, if you take off your tire, and clean the rim before taking it into your LBS, you MIGHT be lucky enough to get them to do it on the spot!)

The wheel was true. Dallas (LBS owner) suggested it was probably the old rear tire. Even though it had beaded perfectly, the 1 year old Crossmark LUST was the fault. Just a minor wobble at high speed. I've just bought a replacement.

Lesson that I learned: It's not always the wheel. The tire may not be seated correctly, or, it just may be an old tire that needs replacing.

soap up the bead and over inflate a little to get the bead to pop in properly. Then adjust your pressure to suit

Just want to post for the next net traveler, the guy who suggested to use wd40 for the bead to pop in, it properly worked perfectly. Try that first.

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