Did my weight cause this to happen to the back tire?
 

When I got off my bike earlier I noticed on the back tire what looks like some of the tire coming out from the rim. I was kind of shocked because the bike is brand new and I have not sat on the bike for more than 10 minutes yet. I am 6' 2" and weigh 243 pounds (about 250 clothed) and the bike weight limit is 250 pounds. I couldn't think of what could have caused this. I have both tires inflated to 43 PSI as the tires say. I deflated the tire, pushed it back in and inflated it back. Most of the tire is back in now but it kind of seems like it might do it again. What should I do to make sure this doesn't happen or cause anything else to happen? I have to have this bike in working condition on March 28th and the last thing I need that day is flat tires.

a million other things would go before the tyre. I am 140kgs and ride 700x32s no problem so i would suggest investing in a good set of brand name tyres and you should be fine in that regard

It's not you, it's most likely the install, but could be the tire.

If the tire isn't spread evenly around the rim and properly seated when mounted, the slack section will lift and blow off. Sometimes newly installed tires have a bit of tube trapped under the bead, which will act like an airbag and jack that area of tire up and over the rim.

It's also possible that the tire was cut from the bead wire if it was installed with tire levers, and excess brute force. If so, the tire is dead, and there's no fix.

Deflate, press the tire in away from the rim, and look there to see if there's any tube visible. Also, massage it around so it's even around the rim. Then inflate to 10-15psi and slowly spin the wheel watching the reference line molded just above the rim's edge to see that it's the ame distance all the way around. (that's why they mold it there, and call it the reference line).

If the tire is OK, a decent job seating it will solve the issue.

250 lbs. seems like maybe a bit much for 43 PSI.

What kind of bike is this, and what size tires?

From the photo it looks like the tire and rim could be a road bike, but 43psi is low for that width and size tire. Are you sure that you are reading the pressure off the tire correctly ?

43psi is certainly an odd pressure guideline. I could see 40 or 45, but 43?. Also, that's super low for a max pressure rating even on a 2" wide tire. I'd expect a modern 70ox32c or similar tire to be rated foe 85 psi or even higher.

Here's some info that might be of help to you in determining the pressure you should ride it. Like all published data, don't take it as Gospel, but as a good starting place to be adjusted either way based on actual experience.

I had that happen recently when the LBS put too little pressure in the tube after they installed a new tire on an old rim. It pushed the tire off the rim, popped the tube. I reinstalled with new tube, seated everything properly and got it up to spec pressure and all good.

43 psi is 3 bar, possibly the absolute minimum for the tire.

Did you buy it at a bike shop? If so, run it down there and say, "Hey, what about this?" Some problems are more easily solved in person than over the internet.

On some of the wide-tire 26" and 20" wheels I've worked with, there is a fair bit of play when an uninflated tire is on the rim. This is handy for changing tires, but also makes it possible to get the tire off-center on the rim, and have this problem when inflated. Solution is to make sure it's reasonably centered on the rim when first airing it up. Better solution would be to use different tires, different rims, or a better combination that didn't have this problem. If you're slapping stuff together in the dark, you shouldn't have to worry about that.

On my road bike with 700-size tires, there is much less slack, I can see this effect just a little bit. Sometimes, it is possible to get a tire a little offcenter, and if you ride on a really smooth road, you can feel it. In normal riding, not so much.

If that's a 2" wide tire, the 43 psi may be about right- I think my Worksman tires are rated for 45 or 50 psi is all. If it's a narrower tire, it should be higher.

Being 243 pounds can cause various problems, but not that one, by the way.

Its a 20" folding bike. I have it outside in a storage house right now and its late. But here is a picture of the bike I found online:

http://ecx.images-amazon.com/images/I/51eD3It3g2L.jpg

I'm pretty sure I read 43 PSI on the side of the tires, but tomorrow I will double check to make sure.

I bought the bike online a week ago StephenH.

Also the width of the tires are 1.75"

Sure the "43" wasn't MM instead of PSI?

I'm quite certain it said 43 PSI but I will check tomorrow.

Here is a pic of the tire where it says inflate to 43 PSI so I guess that is what they want it to be at.http://bikeforums.net/attachment.php...hmentid=439779

Something I found today that I forgot I had was this 20" mountain bike tire. Since the wheels on this bike are 20" I assume it would fit it right? I was thinking of maybe taking off the back wheel (since that is the area that will have the most weight on it on March 28th) and putting this Schwinn tire on it because I assume this Schwinn tire is 10x better than the generic tire on the bike. Its a mountain bike tire but also says for on road use too. Would it put the bike off balance if I put this tire on the back?http://bikeforums.net/attachment.php...hmentid=439782

I said earlier that 43psi was an odd number for a pressure guideline. I now retract that. 43psi is equal to 3 kpa, and I suspect that the tire maker simply converted from the metric without any rounding. In any case, that's a low rating and most decent tires of that size are rated for higher pressures, more between 4 and 5kpa, or about 60-70psi.

Next go round, try for one of these higher pressure rated tires.

So would it be a bad idea to pump the current tire on it to 50 or 60 PSI?

IMO, no. It should be fine. Tires have decent margins for error above the rated pressures. 50 is certainly safe, 60 should be OK also, but don't take this as license to go crazy.

a 43psi casing suggests its pretty craptastic a tire to start with , buy a much more expensive tire , you do get what you pay for.

My Schwalbe (German company) Marathon Plus tire is about $50 each , 406-47.. There are several nominal 20" wheels so better to be specific.


I'd put in ear plugs for the possible loud bang when the casing tears open, or the internal pressure pushes the loose fitting bead off the rim again.

I feel so much better with the security of a difficult to mount, tight tire.

MAYBE. There are two currently common rim sizes that are called 20" ; 406mm and 451mm. See: Measuring Bicycle Rims and Hub Flanges Tires for one will not fit the other.

Let's say you have a 47mm wide tire. Per Schwalbe (http://www.schwalbetires.com/tech_in...ion_pressure); for 250 lbs (114kg) the tire pressure should be about 69½psi (114-75=39; 1.39 x 50 = 69½) That is 60% over the rated max, which I would be uncomfortable with. Does your bike have hooked rims? If not, I'd be replacing the rims.

If you have 406 rim/tire; Marathon's HS420 is available in a 47-406 that is rated to 70 psi. Marathon HS 420 | Schwalbe North America


EDIT: sorry I missed fietsbob's post above - but we are recommending the same tire, IF and ONLY IF you have a 406 rim.

The sidewall pressure if 1/2 of what it takes to blow the tire off of the rim.

Measure the actual width of the mounted tire. I can't find a site that helps get the right tire pressure with that width tire. Proper pressure is a function of vehicle weight and tire width.

So is it possible that over inflation caused the OP problem I mentioned? I believe I had the back tire pumped to about 47 or a littlemore PSI to make up for the slight bit that comes out when you remove the pump nozzle.

NO - tires can be overinflated way beyond the recommended max if intact and if the tube and tire are properly seated when inflated. The bit that comes out when you release the pump nozzle comes almost entirely from the pump. You will not likely lose even a pound of pressure.

My thoughts as well. Perhaps for an off road bike, but this looks like a road wheel. It must be practically rolling on the rim.