Bicycle Mechanics - Can't get the bead to seat properly on a new tire.

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pj7
05-20-07, 06:11 PM
I got some Maxxis Overdrive tires in earlier this week and put them on my bike. (26"x1.75")
For some damned reason I can not get the bead to seat properly. There is about a 5" arc of the bead that refuses to rise out of the "groove" where the rim tape is. I have even ridden 30 miles or so on them to see if that will stretch something into place but no luck, in fact it actually started to wear a nasty spot in the sideall, luckily I caught on to that before anything bad happened.
Is there a trick I am missing? I don't recall ever having this issue and I've mounted many tires before, but then none of my tires had that nifty reflective sideall stripe that made me notice this issue in the first place by dipping down closer to the rim in one spot.


splytz1
05-20-07, 06:25 PM
Did you try overinflating the tire by 20 psi or so to see if the bead would pop into place? This has worked for me in the past.

cooker
05-20-07, 06:25 PM
Sheldon knows all: http://www.sheldonbrown.com/flats.html#seating

Seating a Tire that Dips Inward
If your tire dips inward at one spot, it is usually a sign of an unusually tight fit. This may make it a bit of a struggle to install the tire, but it also means that you can get away with considerable overinflation with no risk of blowing the tire off the rim. Indeed, the best way to seat a "dipping" tire is by temporariliy overinflating it until it "pops" into position.
In some cases it may be beneficial to lubricate the side of the tire. This

EDIT: Dang!


pj7
05-20-07, 06:45 PM
Thanks guys.
I have the tire lubed up and inflated on the rim to about 70PSI (20psi over the max for these tires) and still nothing.
Should I let it sit for a little while and see if it pops in to place?
These tires went on quite easily however, no cursing or tire levers necessary. The funny thing is, the big dip is always in the same spot (near the reflector) when I dismount and remount the tire.

JunkYardBike
05-20-07, 06:59 PM
Thanks guys.
I have the tire lubed up and inflated on the rim to about 70PSI (20psi over the max for these tires) and still nothing.
Should I let it sit for a little while and see if it pops in to place?
These tires went on quite easily however, no cursing or tire levers necessary. The funny thing is, the big dip is always in the same spot (near the reflector) when I dismount and remount the tire.

I read once that if you have very deep rims, using a second layer of rim tape helps push the tube, and hence the tire, up and keeps it from dipping.

JunkYardBike
05-20-07, 07:00 PM
The funny thing is, the big dip is always in the same spot (near the reflector) when I dismount and remount the tire.

Another thought...is the rim round? Or is there a noticeable hop in it?

pj7
05-20-07, 07:00 PM
POP!! There it is!
Thanks guys!

pj7
05-20-07, 07:02 PM
JYB: Yeah, the rims are true, and they are deep sectioned rims.
I guess I wasn't lubing it well enough so I got all sloppy with it, aired them up and the bead seated just fine.

Thanks for the tip on the deep sectioned rims, I'll keep that in mind if I have other tire issues in the future.

MudPie
05-20-07, 07:52 PM
I have the same issue. I'm running tubeless rims, but using tubes. The seal on a tubeless setup needs to be pretty tight. I hate that popping -snap sound, it always causes me to jump. I bought a tub of Tioga beadwax and I notice the popping and snapping occur at lower pressures than without. Needless to say, I recommend this beadwax product.

Camilo
05-20-07, 08:10 PM
I got some Maxxis Overdrive tires in earlier this week and put them on my bike. (26"x1.75")
For some damned reason I can not get the bead to seat properly. There is about a 5" arc of the bead that refuses to rise out of the "groove" where the rim tape is. I have even ridden 30 miles or so on them to see if that will stretch something into place but no luck, in fact it actually started to wear a nasty spot in the sideall, luckily I caught on to that before anything bad happened.
Is there a trick I am missing? I don't recall ever having this issue and I've mounted many tires before, but then none of my tires had that nifty reflective sideall stripe that made me notice this issue in the first place by dipping down closer to the rim in one spot.

This is incredible - yesterday I went to mount the SAME tire (Maxxis Overdrive, 26X1.75) on my wife's MTB (doing a comfort bike conversion). I have mounted many, many tires, mtb and road, over the years and have never given one thought to seating them. Put the tire on, inflate, roll.

I must have spent an hour on these tires. Because of the reflector sidewall line, it was obvious from the get-go that they were not mounting evenly. In my case, the low spot would change every time I messed with it.

It was pretty clear that some parts of the tire were very slightly "out" and one spot was obviously "in". I deflated to about 20 lbs, and messed with trying to get the "out" parts a little bit in, working toward the "in" part and then trying to force that part "out" (following me?). I was using my thumb. It wasn't really working that well - the "in" part was moving around as I manipulated the tire. I then tried bouncing the wheel (inflated 20 lbs or so), as vigorously as I thought I could w/o causing damage or a pinch flat. That seemed to help a little. Then I had the bright idea (as others have suggested) to over inflate. Voila, it worked pretty readily on the front wheel - but before over inflating, I had gotten the tire seated as evenly as I could with my hands. It wasn't perfect, but evidently close enough. I did hear a little pop sound.

Then the rear tire, for some reason seemed to be more stubborn. Eventually, after several cycles of manipulating it as close as I could and then overinflating, it finally worked.

Like I said, I've never before encountered this issue. The one thing I didn't try, which seems to make a lot of sense, is to lube up the bead area of the tire with something wet, like soapy water or windex.

I wonder if those Maxxis Overdrive tires are somehow prone to this?

Sheldon Brown
05-20-07, 08:30 PM
Thanks guys.
I have the tire lubed up and inflated on the rim to about 70PSI (20psi over the max for these tires) and still nothing.
Should I let it sit for a little while and see if it pops in to place?
No. Lubricate it again, and use more pressure, as much as it takes. Might be well over 100. Once the tire pops into position, you can lower the pressure to a more approproate riding pressure.

See also: http://sheldonbrown.com/pressure

Sheldon "PSI" Brown

+-------------------------------------------------------------+
| If brute force doesn't work, you're not using enough! |
| --BOB Simon |
+-------------------------------------------------------------+

pj7
05-20-07, 09:34 PM
No. Lubricate it again, and use more pressure, as much as it takes. Might be well over 100. Once the tire pops into position, you can lower the pressure to a more approproate riding pressure.

See also: http://sheldonbrown.com/pressure

Sheldon "PSI" Brown

+-------------------------------------------------------------+
| If brute force doesn't work, you're not using enough! |
| --BOB Simon |
+-------------------------------------------------------------+


Thanks SB.
I got it to work by using alot of lube and more pressure than I had before. I was scared to go over 65-70psi because of their rating... I know the rating is more of a liability thing than not, but still.
Thanks all.

jethin
09-15-12, 08:51 AM
Just wanted to say that increased pressure fixed the improper seat on my 700x28 road tires. I couldn't get these suckers on right and it was driving me bonkers! Was paranoid to push my tires up past 80 psi (I think 80 -- not sure my pressures gauge is working properly) but it seems to have done the trick.