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Discussion Starter · #1 ·
Yesterday was probably my last ride on the bike for the season. I was leaving work and as the sun was going down quick the temps were getting colder just as quick. I had just left the interstate due to traffic backing up to a stop. Shortly after getting on back roads I found that my rear tire was going flat. I was 10 miles from home no traffic and mostly straight roads. I sped up to hope to get as close to home as I could before it went flat all the way. I got within about 5 miles of home and realized that tire is all the way flat. I slowed down but pushed on, because it was just about dark and there was no shoulders or places to pull off on. By the time I got home the tire was pretty warm but not hot enough where I couldn’t touch it. The tire never came off the bead and visually the tire looks fine. I pulled the nail out and plugged the tire it seems to be holding air.
I was wondering would there be any internal damage to the tire and how would I know?
 

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tires are cheap compared to their importance, but otherwise, I would keep a very close eye on the sidewalls. Look for any cracking of the rubber, especially on older tires.
The weight of bike and rider is a part of it...the same size of tire can fit a range of bikes and the tubeless carcass is fairly stiff so riding a ways on a 250 versus a 750 on the same flat tire is going to be a factor.
 

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You should have kept going fast the cintrafugal force would have kept the tire more round. In any case inspect the title for run flat damage ,any patch it if you feel it’s ok.
I was crushing one time at 100 mph for 1/2 hr. Then I stopped to find only when l slowed. To almost a stop ,tha I had a flat.
tire carcass strength is strong enough to support a lightweight Mc fo quite a long time

Fog
 

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that scenario is the very reason I always carry a can of "flat tire rescue" with me, one check you could make is to reduce the tire pressure to 5 to 8 psi then press the sidewalls all the way round. if there is any internal damage you should feel a soft spongy bit, also check for cracks on the outside, if it feel good and even you may have got away with it.
last time I had to ride on a flat it destroyed the tire but that was the old type of tire
 

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Discussion Starter · #5 ·
I was going about 50 to 60 mph. My thought was exactly what Fog was saying about centrifugal force, but it got really unstable once it lost all the air, which I took it as a message to slow down before I end up in a ditch. I also figure that the bike is pretty light weight that I might be able to get away with it.
I just bought these tires in august so that rear tire is fairly new.
Once I get back home I will look over the side wall really well and see if it is still holding air.
Thanks for your comments and help. This is the first time I have had a flat while going down the road on the bike.
Fun stuff for sure!
 

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Get a new tire. Running on a flat WILL damage the side wall. The only question is, how severe the damage is.

Do NOT settle for an external inspection. Demount the tire from the rim and look at the sidewalfrom the inside.

If you see a great many creases and anything that looks like powdered rubber, get a new tire.

Most if not all tires for motorcycles are single ply sidewall.

Maybe tires for heavy baggers like a Goldwing or a HD Tour Glide will have a 2 or 3 ply sidewall for the extra load.

When you ride on a flat, the sidewall flexes and the cords will separate. That will leave a bunch of powder like rubber inside.

If you repair that tire and run it at normal pressures it could blow out.

A sudden and unexpected loss of pressure would be disconcerting at best, possibly catastrophic to the motorcycle and rider.
 

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I'm with apriliarider on this one. You were probably OK up to the point where you rode an additional 5 miles on a totally flat tire. I can see a lot of damage being done in that 5 miles. I'm not even sure how you rode 5 miles on a flat without either falling off, or damaging the rim; you must have been totally upright and going VERY slow??

Definitely worth removing the tire from the rim and inspecting very carefully....
 

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Discussion Starter · #8 ·
I can assure you I wasn't going slow. I was doing 45 to 60 mph.
The bike will be put up for the winter. That leaves me plenty of time to check out the tire or replace it. I will make sure I post some pics of the outside of the tire.
 

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IME, the sidewalls are so stiff and the bike so light that even with no pressure, the tire never goes very visibly flat.

I'm embarrassed how many times I've done this. All responsiveness goes to hell, braking and steering suck and you'd be insane to accelerate hard, but a totally flat rear can be ridden in emergency by someone under 150 lb. with with decent skill with no real issue. I speak from experience.

If the sidewall hasn't flexed all that much, and the tire isn't decrepit or abused already, I wouldn't be too worried about it. Hell, I asked a trusted bike mechanic about fine cracking on a tire once, and he was honest enough to say that superficial UV and oxidation damage was not worth worrrying about.

Of course this is a piece of mind and finances decision. If you want total assurance or the cost is not going to lose you sleep, replace. I'm not sure what anyone expects to happen to the tire. Is it getting a bit of accelerated wear, sure. I'm skeptical of catastrophic consequences though.

ha, I forgot that my avatar is relevant!
 

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I was a mechanic for over 20 years. By that I mean, I worked in that career extensively. I’ve worked tires since the 1980s.

I replace my own and have done so since the 90s. Not all sidewalls are created equally. My Aprilia weighs in at just over 400 lbs. it is not a heavy motorcycle.

It weighs not a great deal more than an EX500. I’ve gotten a flat on it and ridden for a number of miles before realizing it was flat.

The 190/50 tire has a very short sidewall. It will not de-bead when flat, even after a dozen miles. Even with that short and stiff sidewall, the tire sustained enough damage that there is no way I’d simply plug patch the hole and ride on it again.

Once the cords of the internal carcass start separating, the chances of a sudden failure increase exponentially.

A blow out, sudden loss of all air pressure while cranked over in a fast sweeper could potentially be a catastrophic event.
 

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Here's my 2 cents.

I think it's less of a technical question and more about risk assessment.
We got pretty much the full range of opinions, all of them valid on their face.

Some folks say, look at the tire, if it looks good, run it, why worry?
Other folks say: replace tire, don't take any chances.

So, OP is free to make his own considered decision about the risks involved, it's his risk after all,
and one thing's for sure, if he ends up in hospital, he can't say he wasn't warned.
 
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