Has anyone ever used a run flat..

...on a motorcycle; in the capacity that it was designed for? Meaning that they've experienced loss of air and the tire still gets them home, without any drama?

Just curious. If it'll get a car home... I'd think it would not self destruct on a motorcycle. Or would it... due to the difference to the way that the car tire sits on the motorcycle wheel's bead hump as instead of being locked in?

I offer this very good article again for review (we have seen it before on this forum) and a couple of pic's I took from it to illustrate my question:

http://www.goldwingfacts.com/forums/...-rim-tire.html

http://i66.tinypic.com/20jsaie.jpg

http://i63.tinypic.com/14albfp.jpg

If a run flat car tire is locked into the wheel's rim, I can logically understand how it would still stay on the rim and the stiffer sidewalls would maintain enough tire structure. If they are not locked in (as on a motorcycle wheel) I would venture a hypothesis that the tire would eventually self destruct due to eventual lateral movement of the tire within the rim?

Those two pictures are great for conversation and speculation! What they lack in actuality is 30+ pounds of air pressure which IMHO would change the appearance and seating of the tire beads to the rims. I've always managed to witness the mounting and removal of my CT's to my cycle rim. In the case of a non run-flat radial the tire seats with a distinctive "loud pop" indicating that has in fact seated. Same goes for "breaking the bead" for removal when the Gates Tire Machine is used to unseat the tire bead. Never had the opportunity to witness a "run flat tire" tire installation/removal so I won't comment on that. Several of our members are in the "Tire Business" i.e. Shooter and WJDuke come to mind. I'm sure they can provide some excellent input to this conversation as they've most likely "seen it all" in their professions:icon_wink:

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Originally Posted by bob109

Those two pictures are great for conversation and speculation! What they lack in actuality is 30+ pounds of air pressure which IMHO would change the appearance and seating of the tire beads to the rims. I've always managed to witness the mounting and removal of my CT's to my cycle rim. In the case of a non run-flat radial the tire seats with a distinctive "loud pop" indicating that has in fact seated. Same goes for "breaking the bead" for removal when the Gates Tire Machine is used to unseat the tire bead. Never had the opportunity to witness a "run flat tire" tire installation/removal so I won't comment on that. Several of our members are in the "Tire Business" i.e. Shooter and WJDuke come to mind. I'm sure they can provide some excellent input to this conversation as they've most likely "seen it all" in their professions:icon_wink:

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Good points. But the "pop" that you hear when seating the bead...

...is that just the bead popping over the hump but still sitting on it under pressure? Or is it actually "completely" locking in behind the bead hump?

For the sake of clarity, I extracted another remark from the aforementioned article that I posted, that discusses this:

The bead hump is quite different in shape and size from a car rim to a motorcycle rim. The bead hump is a little larger on a motorcycle rim versus a car rim because of the extra forces generated while the motorcycle is cornering. The bead hump is placed in a VERY critical location on both rims. On a car rim it is 21mm from the bead flange to the center point of the bead hump. On a motorcycle it is placed at 16mm from the bead flange to the center point of the bead hump. Why this is critical, is the respective tire that fits the respective rim will have a matching size bead seat of both the rim and the tire. So by placing a 21mm bead seat (car tire) in a spot only allocated for 16mm. (Motorcycle rim) the car tires bead seat is sitting on the bead hump not down by it allowing the bead hump to help hold the tire on the rim. Thus this where and how a car tire can dismount from a motorcycle rim.



Where is Shooter and Wayne?

I'm around and have made my opinion on this subject well known. Shooter is a proponent, I'm opposed. There you go. Two guys in the business with different opinions. If there's no evidence of a failure from the bead seating, who am I to say don't do it. Personally, I won't. I just don't like the look of it.

Wayne

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Originally Posted by wjduke

I'm around and have made my opinion on this subject well known. Shooter is a proponent, I'm opposed. There you go. Two guys in the business with different opinions. If there's no evidence of a failure from the bead seating, who am I to say don't do it. Personally, I won't. I just don't like the look of it.

Wayne

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Wayne, can you elaborate on that last part? Exactly WHAT do you not like about the look of of (it)?

As far as my original question in this thread; do you think a "run flat" would perform in the same aspect on a M/C wheel, if it lost air.... as it would (as designed) on a car wheel? I do not have a TPMS so this is why I am asking this question.

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Originally Posted by willtill

Wayne, can you elaborate on that last part? Exactly WHAT do you not like about the look of of (it)?

As far as my original question in this thread; do you think a "run flat" would perform in the same aspect on a M/C wheel, if it lost air.... as it would (as designed) on a car wheel? I do not have a TPMS so this is why I am asking this question.

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Just as the photo shows. The bead isn't designed for that wheel. The very first time I saw that, a few years ago, I didn't like it. Will the tire do it's job in a loss of air situation, I believe it would. That doesn't convince me. This is my opinion. I won't get into an argument about it. I stick with motorcycle tires.

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Originally Posted by wjduke

Just as the photo shows. The bead isn't designed for that wheel. The very first time I saw that, a few years ago, I didn't like it. Will the tire do it's job in a loss of air situation, I believe it would. That doesn't convince me. This is my opinion. I won't get into an argument about it. I stick with motorcycle tires.

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Thanks Wayne. Just looking for opinions and discussion, not arguments. :039:

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Originally Posted by willtill

Thanks Wayne. Just looking for opinions and discussion, not arguments. :039:

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I know Will....

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Originally Posted by willtill

...on a motorcycle; in the capacity that it was designed for? Meaning that they've experienced loss of air and the tire still gets them home, without any drama?

Just curious. If it'll get a car home... I'd think it would not self destruct on a motorcycle. Or would it... due to the difference to the way that the car tire sits on the motorcycle wheel's bead hump as instead of being locked in?

I offer this very good article again for review (we have seen it before on this forum) and a couple of pic's I took from it to illustrate my question:

http://www.goldwingfacts.com/forums/...-rim-tire.html

http://i66.tinypic.com/20jsaie.jpg

http://i63.tinypic.com/14albfp.jpg

If a run flat car tire is locked into the wheel's rim, I can logically understand how it would still stay on the rim and the stiffer sidewalls would maintain enough tire structure. If they are not locked in (as on a motorcycle wheel) I would venture a hypothesis that the tire would eventually self destruct due to eventual lateral movement of the tire within the rim?

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I rode home from work-6 miles-on my Michelin run flat without tire pressure. The valve stem (metal) went bad and I did not realize it at the time. I thought about going to the house and get my mounted MC tire and changing it in the parking lot but rode the bike around the parking lot a couple of times and it felt ok. I did not go much faster the 35-40 miles per hour. I did think the rear end felt squishy so I was careful. Got home, felt the tire and it was not over heated.

Not sure I would want to do it on the highway but I would go father than the 6 miles if conditions were right.

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Originally Posted by valkmc

I rode home from work-6 miles-on my Michelin run flat without tire pressure. The valve stem (metal) went bad and I did not realize it at the time. I thought about going to the house and get my mounted MC tire and changing it in the parking lot but rode the bike around the parking lot a couple of times and it felt ok. I did not go much faster the 35-40 miles per hour. I did think the rear end felt squishy so I was careful. Got home, felt the tire and it was not over heated.

Not sure I would want to do it on the highway but I would go father than the 6 miles if conditions were right.

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Real world experience. That is good to hear. Thanks!

I just pulled a worn out Run Flat off my bike last week but never had to test the Run Flats capabilities.

I've also lost pressure on a runflat tire on a motorcycle, but not on an F6B. I can echo what was said by valkmc, only I didn't realize it for about 10 miles. I was riding my NM4 with a Bridgestone RF out in the rurals around here running between 40 and 60mph. I only noticed that the rear end was a bit squishy after I stopped for fuel. When I got back on the bike it felt like I was running on 10-15psi...kinda the way a set of drag tires feel on a car. I was pretty sure where I might have picked up the screws (yep, 2 of em) (which is why I thought it was about 10 miles of riding on un-inflated tire) and it being a Sunday in the middle of nowhere with a closed store, I had no choice but to try to limp home or wait several hours for a tow...so I rode home on it. I put just at 34 miles overall on that tire before pulling into my garage. The tire worked pretty well.

As for beads that lock into place...those only happen on rims called beadlockers. Regular automotive and motorcycle rims are not beadlocking in the true sense. The lip that the bead(s) rest against are a tad taller than the beaded rings on the tire and once the tire is installed, along with enough internal pressure to "seat the bead", the tires bead generally doesn't move unless you have a blowout/lose nearly all pressure to the point you shred the sidewall or throw the tire (which happens when both beads come unseated and your rim rolls at least one side off)

To give you an idea of what a car rim looks like in comparison to the motorcycle rim posted...this is a runflat tire on a car rim in cross section.
Attachment 22800
Notice a couple of things...the profile of the rim area is not that different from the motorcycle rim. As long as the bead can seat against the rim, it physically works the same way. Second, the car tire on the motorcycle rim is a regular type of car tire. Notice the extra rubber thickness of the sidewall on the runflat. While it's still only a couple of ply in tread strength as opposed to the multiple plys of the motorcycles sidewall, it has an excessive amount of rubber throughout the sidewall...looking almost MC tire-like in overall thickness. This is how it can handle the added abuse of running an automobile without pressure for somewhat prolonged distances compared to a normal car tire.

I'm not advocating for or against the use of a car tire here...I certainly wouldn't run a normal tire on a bike, not after seeing just what happens when a sidewall goes (have scars to show for it). I prefer the ride of a bike tire on a bike but I have no issue putting a runflat CT on a bike and accept the risk in doing so.

Below is a single side beadlocking rim from a truck wheel. Notice the bead is physically locked into place between the inner and outer plates. This keeps it from peeling away from the rim and allowing the tire to float off the wheel.
Attachment 22801

Thanks Patch, for your experiences. :yes: All of this is very informative. :icon_cool:

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Originally Posted by valkmc

I rode home from work-6 miles-on my Michelin run flat without tire pressure. The valve stem (metal) went bad and I did not realize it at the time. I thought about going to the house and get my mounted MC tire and changing it in the parking lot but rode the bike around the parking lot a couple of times and it felt ok. I did not go much faster the 35-40 miles per hour. I did think the rear end felt squishy so I was careful. Got home, felt the tire and it was not over heated.

Not sure I would want to do it on the highway but I would go father than the 6 miles if conditions were right.

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Great real life input. What do you have against Idaho anyway?

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Originally Posted by HBWinger

Great real life input. What do you have against Idaho anyway?

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Nothing , I planned on riding through it on my return trip from Alaska a few years ago until my C-14 screwed up and I had to take a different route. I'm a school teacher so iwill get there one of these summers.