# Out of round tires wobble



## PoorCyclist (Oct 14, 2010)

I just got these tires here they came mounted on the wheels that came with the bike

http://reviews.roadbikereview.com/blog/hutchinson-piranha-cx-tubeless-ready-tire-review/

They are so lumpy and out of round I can feel the wobble, feeling like the bike is galloping.
(when spinning the wheel, I could see the treads vertically move up and down) 
They are made in France, at $40+ per tire I didn't think they should be that bad?

Is it a mounting issue? I'm currently running tubed, thanks


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## krisdrum (Oct 29, 2007)

Are the wheels they are mounted on true and round?


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## thatdrewguy (Aug 7, 2009)

my bet is on rim & bead interface and that the tire is not seated correctly. Deflate tire, squeeze tire around the rim making sure the tube is completely inside the tire, throw some soapy water along the bead and reinflate... no more wobbles.


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## JCavilia (Sep 12, 2005)

It could be a mounting issue, or untrue rims, or defective tires. Look for rim issues first. Spin the wheel and watch the rim as it passes the brake pads. Try to see if the rim has hops and dips (radial untrueness, or out-of-round). 

If the rims seem okay, spin the wheels again and identify the spots where the wheel seems "high." Try to see if the tire at those points is not fully seated. There's usually some kind of a line molded into the tire side a little above the rim interface. See if you can tell whether the tire is too high at some points. Some tires fit loosely on some rims, and more care has to be taken to seat them consistently. You can partially deflate and try to work the tire into better position.

If you can't get them better that way, the tires may be badly made. Even if that's the case, you may be able to get them into good enough shape to perform acceptably. You say you can see the hops and dips. What's the amplitude? How much difference between the highest and lowest spots? (to determine, hold a straitedge across the stays or fork blades so it just touches the highest spot, then rotate to the lowest spot and estimate the space. If it's within 2-3mm, that's not unusual, and should be barely noticeable, if at all.


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## PoorCyclist (Oct 14, 2010)

The rim is new and true I dont see the pad going out of the rim

I'll try to play with the seating process
The amplitude is not 2-3mm, at least 5mm!


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## PoorCyclist (Oct 14, 2010)

Hey, I deflated and pinched all around to reset the bead, it seems to look better than before..
while the tire is no near perfect, it appears to be bulging around the valve stem.. no matter how I inflat it, sometimes I would get a dimple on the sidewall each side of the valve stem.. I am using a prestaflator on a threadless valve stem so it's kind of tricky if I don't press the stem via the outside of the tire, but it makes no difference in the end result.

Is it a inner tube quality or wrong size ?


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## bas (Jul 30, 2004)

PoorCyclist said:


> Hey, I deflated and pinched all around to reset the bead, it seems to look better than before..
> while the tire is no near perfect, it appears to be bulging around the valve stem.. no matter how I inflat it, sometimes I would get a dimple on the sidewall each side of the valve stem.. I am using a prestaflator on a threadless valve stem so it's kind of tricky if I don't press the stem via the outside of the tire, but it makes no difference in the end result.
> 
> Is it a inner tube quality or wrong size ?


Does the inner tube have the tire size marked on it? (mine do).


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## JCavilia (Sep 12, 2005)

Try deflating again, being careful to disturb the rest of the tire position as little as possible. With the tube uninflated, push the valve stem way in, so it disappears as far as possible into the rim. Then try to work that section of the tire bead down so it's seated deeper in the rim. Then, hold the tire in as you begin re-inflating, and watch to see that that section of bead stays fully seated. If it slides up or bulges, deflate and start again.

Sometimes, with some tube/tire combinations, the thicker section of the tube around the valve interferes with the tire seating, unless you get it completely inside the beads before you inflate. The method I described can sometimes correct that.


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## PoorCyclist (Oct 14, 2010)

OK I will try that, looks like I have to use an hand pump to try your suggestions.

is it possible it just a poor tube combination, maybe tire is smaller diameter (seems tight and I can see they left some marks from using metal levers) and the tube is possibly a loose fit around the rim, in that case when trying to fit a bigger circle (tube) into a smaller one, something has got to bulge out?


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## dysfunction (Apr 2, 2010)

Does the head slip off the stem when you try to inflate the tube? If so, try tightening the head just a smidge, mine does not do so.. especially at lower pressures.

Just thought about another option, screw on a schrader adapter and screw the prestaflator hose on to that for this attempt.


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## PoorCyclist (Oct 14, 2010)

dysfunction said:


> Does the head slip off the stem when you try to inflate the tube? If so, try tightening the head just a smidge, mine does not do so.. especially at lower pressures.


It's one of those smooth threadless stems so it keeps going inside the rim. (but from what I read, you want the stem inside the rim to begin)

I have been using a prestaflator but it's pretty annoying because you need to push down hard on both sides to get the tube to start inflating. I will be using a hand pump tonight, I only have a small portable one but the head works well.


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## dysfunction (Apr 2, 2010)

I'll have to go play with it in a bit (this after-evening since my fam's not home).. I have a prestaflator and use threadless valve stems (not-quite exclusively) But I've been on the IR list, so haven't touched it in over a month.


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## JCavilia (Sep 12, 2005)

PoorCyclist said:


> OK I will try that, looks like I have to use an hand pump to try your suggestions.
> 
> is it possible it just a poor tube combination, maybe tire is smaller diameter (seems tight and I can see they left some marks from using metal levers) and the tube is possibly a loose fit around the rim, in that case when trying to fit a bigger circle (tube) into a smaller one, something has got to bulge out?


You can probably get it to work. Tubes are both flexible and stretchy, and they're contained by the tire when pressurized, so a little mis-fit is insignificant, unless you don't get the tire seated properly. Some tires are a poor fit on some rims -- that's a more realistic possibility.

Your remark about the hand pump prompts the question: how have you been inflating? If you're using a compressor, that may be one source of your problem. Inflating too quickly can make it hard to monitor proper seating of the tire. A good floor pump is almost universally recognized as the best way to inflate road bike tires. You can go a little at a time and check things as pressure increases.


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## dysfunction (Apr 2, 2010)

He's using a prestaflator, which utilizes a compressor. Since it's a trigger you can easily control the amount of airflow into the tube, but it takes some practice and intent to do so. I got one for mounting tubeless mtb tires and pretty much use it for everything (cept when I drive to a ride start).. but I do recall it taking some practice to get comfy with it.

Ok, I went out and reseated a tire. So all I did to get the silca type head on was to press down on the tire opposite the valve stem

Then, slipped it on so that the rubber o ring seated in the recess created just after the threads for the valve cap, then inflated slowly to about 60psi, at which point the tire was fully seated on the bead and I inflated the rest of the way. My compressor is set, btw to 120psi output on this particular air line.


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## PoorCyclist (Oct 14, 2010)

I used a hand pump and I would have to say result is the same, more controlled, yes, maybe slightly better, but the 1/4 of the tire bead seats further in the proximity to the valve area. I think I did everything right, it's not that hard. Using the prestaflator to push in the stem to start inflating will result in a dimple on the sidewall (probably not a good thing), using a hand pump does not have it.

I tried to pry tire the off to look at what size of tube is inside, but not successful.. it seems incredibly tight I can't slide the lever to get the bead off, would soapy water help with this? 
I don't think I can change a flat with this tire on the field.

I am not sure because if these are made to tubeless ready they fit tight, the reviews I have seen have this complaint..

With 3-4mm out of round these tires might be unnoticable at 30 PSI in the dirt I think.. the higher PSI the worse it gets.. Well it is a CX tire, it's a shame because it rolls really well in the pavement though.

I think I am going to get another tire and bringing it LBS to change them.


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## Ventruck (Mar 9, 2009)

I've have this with my current Serfas Seca RS pair. Also doesn't help that the color strips look like they were applied by some guy with Parkinson's (no offense) and a paint brush. I just accepted it since it isn't felt, via tire deflection and whatnot.


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## Kerry Irons (Feb 25, 2002)

*Visual inspection*



PoorCyclist said:


> the 1/4 of the tire bead seats further in the proximity to the valve area.


If I read you right, there is a section of the tire that is not even with the rest of the tire bead, and appears to be sitting "lower" (i.e. down in the rim sidewall). It means that the bead of the tire has not "snapped" into place in the groove in the inner sidewall of the rim. If this is the case, you might try some talcum powder along the bead to help it slip into place. Soapy water will work but using the powder means that you will have that slippery surface when you are out on the road changing a flat tire.


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## PoorCyclist (Oct 14, 2010)

wow, I spent so much time on this, I can correct the lateral distortions at a low pressure by hand, but not the inevitable lift around the valve area. Same for both tires.. if I inflat it to like 70PSI+ I could get 1/4" radial runout... Maybe if powder was applied to the tube and it can move better inside the tire as it gets inflated, that may help, I am just guessing though. But I am still thinking the tube is not optimal with the tire.. I suppose if I just run it low enough pressure and run in the trails like it was made to.. I won't feel the bobbing.

There is a seam line on the sidewall and I can see almost 1/4 of the tire on the valve side is showing the seam. and the rest of the tire does not.

Thanks for the help guys..


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