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We took our tandem out this afternoon and two miles out our Continental Duraskin rear tire blew. The sidewall blew out and was unrepairable so we had to walk home. It's not like we have a lot of weight on the back of the tandem, I only weigh 110 pounds. The tire only had 70 miles on it so that was disappointing. We have been using this type of tire for a couple of years now and find they are better on plain flats but the sidewalls puncture easily. Are there any other tires out there that are better? We were now thinking of carrying a cheap foldable tire in case this happens when we are further away from home. Any suggestions?
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This is very unusual. What pressure were you running? What does the blow-out area look like (star, cross, pin hole, wear, etc)? Does the tire fit the rim? Having the tire go (vs a tube) says that something is wrong that needs to be corrected. To me, at least.
+1 The contis should last a decent time and fail through tread wear not blow out. Either the tyre was defective or the installation, adjustment was wrong or something hit it while you were on the road. Probably the latter was the case - I had a brand new tubular ruined 10 years ago after a piece of flint cut straight through the sidewall on its first ride, so strange things do happen. That said you should closely inspect the bike for anything that could have caused it if you didn't see anything in the road that could have caused it.
Another comment: 'most durable' is a compromise - personally I buy racing tyres with the thought that if a soft tread compound saves one crash ever (big difference in the wet), then the extra costs are, more frequent changes and occasional puncture are worthwhile. That said, most punctures are avoided by removing grit from the tyre after each ride.
Your mileage may differ...
Nothing can replace just plain old keeping your eyes open. No tire will survive running over sharp objects.
We had gator skins on our tandem. We only got about 1k miles on them before they just wore out. We are a three hundred lb team and started having to many visits from the flat fairy. It all ended ugly while going downhill about 30 mph when the front tire flatted rather quickly. We managed to stay upright and got it stopped but the tire was ruined. We flipped the bike over to inspect it and see if we could get it fixed enough to get home about three miles. Red Rider then noticed a deep cut all the way across the rear tire. We got it fixed enough to go the 1/2 mile to the LBS where we bought Armadillos. We have about 1500 miles on them and they show very little wear and we have had no flats. http://www.youtube.com/watch?v=sKCSGbWbPyE
Our tire size is 700 x 28 Continental Gator (Duriskin) Skin with 700 cc Velocity Dyad rims. We keep the pressure at 100. It looks like a tear in the sidewall, not an actual cut. Do you guys carry a foldable tire with you when you ride? We have had a blowout on the sidewall once before about 3 years ago.
100psi seems a little low for a tandem, but at least it wasn't over-inflation that did it. I run 115 on the Conti "Ultra-Sport" 700x28 that came with our CoMo. Still rolling, after 2k miles. Front looks new, back is starting to get square edges. We do not carry a spare, don't even own one at this point, but probably should pick up at least one. I don't know about rotating; that just seems like work. It isn't like we are racing in the rain or anything. I would definitely say sidewall blowouts on tires are rare. Unexplained ones even more so. You have now had 2, and that seems like an awful lot for something so rare.
We had gator skins on our tandem. We only got about 1k miles on them before they just wore out. We are a three hundred lb team and started having to many visits from the flat fairy. It all ended ugly while going downhill about 30 mph when the front tire flatted rather quickly. We managed to stay upright and got it stopped but the tire was ruined. We flipped the bike over to inspect it and see if we could get it fixed enough to get home about three miles. Red Rider then noticed a deep cut all the way across the rear tire. We got it fixed enough to go the 1/2 mile to the LBS where we bought Armadillos. We have about 1500 miles on them and they show very little wear and we have had no flats. http://www.youtube.com/watch?v=sKCSGbWbPyE
Woohoo, Chris! We have 2000 miles on our original Gatorskins and had the first flat two weeks ago. Still plenty of good tread, but we may try the Armadillos when we need new tires. Not sure we are willing to ride through broken glass like in the video. You can try that and let us know how it goes....
Steve
Nothing's puncture proof.
I had a puncture while running Armadillo's on my tandem but it was from a broken beer bottle shard roughly the size and shape of a sword. I don't think that anything would have stopped that. What I don't like about Armadillos is the sidewalls are so stiff that they ride like an ox cart.
I've been using 28mm gatorskins on my tandem for a couple of years. So far I've been satisfied enough that, if I were buying tires today, I'd buy the same thing. I have a 28mm folding tire to take with me as a spare on tours but I don't typically carry it with me on day rides.
I don't get a whole lot of flats. I've had one so far this year and none at all that I can remember all last year. Unfortunately, a high percentage of the flats that I get involve cutting down a sidewall or something that ruins the tire. I guess that's just the breaks.
Our tire size is 700 x 28 Continental Gator (Duriskin) Skin with 700 cc Velocity Dyad rims. We keep the pressure at 100. It looks like a tear in the sidewall, not an actual cut. Do you guys carry a foldable tire with you when you ride? We have had a blowout on the sidewall once before about 3 years ago.
The Gatorskins actually have a pretty good reputation and seem to do a pretty good job of balancing durability with performance. A more robust tire like the Panaracer Pasela might be a bit more resistant to the occasional road hazard / puncture threat, but not feel as lively as the Gatorskin.
As for tire pressure, the three things that I use to guide how much to run in a tandem tire are:
1. What's the manufacturer's maximum recommended pressure (Conti's is 116 for your tires)
2. How much tire pressure do I need to put in a tandem's rear tire to get the right shape, e.g., just a slight bulge when both riders are sitting on the tandem. If the tire looses 1/2 of it's sidewall height, then there's not enough tire pressure and the risk of pinch flats and sidewall punctures is increased dramatically. If there is no bulge, you lose some comfort and also increase rolling resistance on roads with less than perfectly smooth surfaces, e.g., chip seal, concrete, weathered asphalt.
3. What works best for you and your stoker? Running a tandem's tire at or below the "normal" recommended psi is often times a bit too low given the extra weight that a tandem carries. Even though you may only weight 110lbs, the rear wheel is carrying all of your weight and about 1/2 of your captain's weight given where the center of gravity falls on a tandem with two average size riders. Therefore, running at 100psi may or may not be enough for your team IF it doesn't give your tire the proper shape. Given that you are reporting a higher than average number of sidewall punctures and now a sidewall tear, I would suspect that -- absent a mis-aligned brake shoe rubbing against the tire or road hazard -- you probably should be running your tires with something closer to the 116 max psi. It would also be a good idea for your captain to look at where he's positioning the tandem on the road. If he tends to ride very close the shoulder where all of the road debris collects, flats will be a much more common occurance than if you rode right at the fog line or along the right track of the traffic lane when there is no fog line as those areas are almost always swept clean of road debris.
As for us, as mentioned in several other posts on tire topics, we've used the same brand and model of narrow foldable racing tires for the past decade, in one of two different sizes -- 700x23 or 700x25 -- inflated to 135psi and 145psi, respectively. Our total team weight is about 275-285lbs, depending on the time of year. I don't want to jinx myself, but we have very few flats and the occassional flat that we do have clearly comes from something that comes through the tread, not the sidewall. We usually have a spare foldable tire on the bike, strapped under the stokers stem/my saddle when we participate in century rides, rallies or tours and it's often times on there even for our local rides if I don't bother to remove it between events.
Nothing's puncture proof.
I had a puncture while running Armadillo's on my tandem but it was from a broken beer bottle shard roughly the size and shape of a sword. I don't think that anything would have stopped that. What I don't like about Armadillos is the sidewalls are so stiff that they ride like an ox cart.
I run 27X1.25 Armadillos. I think the gum sidewalls offer much more protection to the side walls. Years ago I ran K2 tires with thin sidewalls. I found that the ozone and UV caused the sidewalls to break down. Moisture would enter and make its way to the bead which would then rust.
Our team weighs about 400 pounds. We run 125 pounds in our tires, which is within the ratings for the Armadillos. Gaterskins have a much lower max pressure rating.
I've been using 28mm gatorskins on my tandem for a couple of years. So far I've been satisfied enough that, if I were buying tires today, I'd buy the same thing. I have a 28mm folding tire to take with me as a spare on tours but I don't typically carry it with me on day rides.
I would like to have a folding tire but I can't find one in 27X1.25. The local tandem dealer said that it was much safer to carry a non-folding tire twisted into three loops. I guess folding tires don't stay on as well.
I don't get a whole lot of flats. I've had one so far this year and none at all that I can remember all last year. Unfortunately, a high percentage of the flats that I get involve cutting down a sidewall or something that ruins the tire. I guess that's just the breaks.
We took our tandem out this afternoon and two miles out our Continental Duraskin rear tire blew. The sidewall blew out and was unrepairable so we had to walk home. It's not like we have a lot of weight on the back of the tandem, I only weigh 110 pounds. The tire only had 70 miles on it so that was disappointing. We have been using this type of tire for a couple of years now and find they are better on plain flats but the sidewalls puncture easily. Are there any other tires out there that are better? We were now thinking of carrying a cheap foldable tire in case this happens when we are further away from home. Any suggestions?
I got a bad pair of continental gatorskins last summer when I replaced both tires at once on my single due to a bad cut on the front. The first tire blew the sidewall at about 25 miles while hanging in the garage. The 2nd one lasted a few days longer, and blew out again while hanging in the garage. In spite of this, I've continued to run the gatorskins on our tandem, and wouldn't hesitate to buy the next ones.
I normally watch the sidewall of the gatorskins fairly closely. After they begin getting some age, the ones I've used start to have threads break and begin to unravel. When they start doing that, I generally go ahead and replace them regardless of how much tread I have left.
We don't carry an extra tire with us...I figure I can probably boot one well enough to limp home or to the truck if we have to. If not, a cell phone call to one of the kids to rescue us will at least get us home, if not ridiculed in the process.
Our set-up...
Riders: 400 lbs., more with occasional luggage.
Bike: '97 Burley Duet
Tires: 700x28, Armadillos, 100 psi, 900 miles, no probs.
How high above the recommended pressure can/should one go with a tandem tire? We run 26x1.5 Avocet Cross IIs w/ Kevlar belt on a Santana Fusion. About half of our rides are on crushed limestone trails (the other half on the road). The Avocet is rated up to 85 psi to that's what I've been running. At a group tandem ride last week, another team recommended going to 100 or 110 when riding on the road. Is that OK? Our team is ~310 lbs.
We've had good luck with Maxxis Re-Fuse folding tires, 700x25. We are a just-under 250-lb duo
We've had good luck with Maxxis Re-Fuse folding tires
I have been cautioned about running folding tires on a tandem by an experienced tandem rider/bike shop owner. He didn't mention ever having any issues himself but felt that a wire bead tire would be less likely to come off of a rim and tangle in a wheel in a "blow out" situation. I rode with folding tires for more than a year without issues, including some flat tires at higher speeds. I would like to run some 700x28c folding tires when the current set of tires wears out but I am reluctant because of the warning I received.
I noticed that folding tires have been mentioned here as choices (not counting the emergency/get me home tires) and was wondering what others experiences have been with folding tires.
We are a 305 pound team...run Conti Grand Prix 4 Season 700 28c at 125 pounds. Great ride, good grip, very predictable handling and have been pretty puncture resistant. They do wear quicker than I'd like but are worth the piece of mind.
Bill J.
After using a variety of tires from Michelin and Conti, I've been running Serfas SECA 700 x 25 wire beads (at recommended 125 psi) with very good results - one flat over the past 1800 miles. I forget who recommended these, but I would definitely buy another set. At $25 each, they're a steal. I believe they have some sort of belt that they call the "FPS" (Flat Protection System) which, apparently, works.
The only obvious manufacturing defect I ever encountered was on a tire from Specialized, which suddenly developed a sidewall bulge (got home by reducing the tire pressure).
The only time I carry a spare tire (folding) would be on a multi-day, point-to-point trip. However, I do carry some duct tape (good for lots of repairs) that I would use to cover a tire side wall failure (from the inside of the tire). Been told a dollar bill will do this job as well, if the affected area is not too large.
Last week a local tandem couple went down after a "front flat" while going downhill into a turn. I heard that they may have had low pressure in the front, but definitely no flat protection. I can't imagine not having SOME kind of flat protection on our tandem... I understand that the couple are doing well without serious injury.
Have never had a folding trire blow off the rim in the last 50,000-some miles.
Have used a folded dollar bill to bridge a gap due to sliced up sidewall. Works fine.
Have had a few tires blow out, front and rear (but not simultaneously!), and always been able to ride it out. Just don't grab the brakes when it happens . . .
Blowing the front at speed 30+ mph coming downhill is no fun . . . a bit like riding a bucking bronco; been there, done that.
Just our observation/experience . . . yours could vary!
Be safe out there and make a habit of inspecting your tires regularly.
Pedal on TWOgether!
Rudy and Kay/zonatandem
Re-reading this thread I'm wondering what kind of brakes you are using.
If you're using rim brakes and if they touch the tire AT ALL, they'll eat through your tire and cause a blow out in no time at all.
. The sidewall blew out and was unrepairable so we had to walk home. ?
Take an old tire, and cut out a 2" long section. This will make a tire boot that will fix virtually any blow out. It will bump with every rotation of the tire, but it will get you home.
Less severe blowouts, a dollar bill works nicely. (or a $20 if you like expensive components.)
Last week a local tandem couple went down after a "front flat" while going downhill into a turn. I heard that they may have had low pressure in the front, but definitely no flat protection. I can't imagine not having SOME kind of flat protection on our tandem... I understand that the couple are doing well without serious injury.
I assume for flat protection, you mean something like slime, or a tufo strip.
People routinely race single bikes on very light tires with no "flat protection."
If anything you're more likely to wreck a single bike with a front flat than a tandem, given that the tandem has a longer wheelbase and is more stable.
So I can definitely imagine, and do, ride a tandem without "flat protection".
I guess you can argue that the tandem is capable of greater descending speeds than a single on the same grade. However, its kind of academic if you're over 50mph on either.
So I guess its a risk reward trade off. If you race, the slight risk of a blow out, and then a possible crash, imho is offset by thedecreased rolling resistence.
If you wanted to be sure to never crash from a blowout, there are solid tires available.
If anything you're more likely to wreck a single bike with a front flat than a tandem, given that the tandem has a longer wheelbase and is more stable.
I wouldn't want to bank on that...
Unless you have the flat at a point where you can keep the tandem pointed in a straight line until it comes to a stop, the inherent added stabilty of the long wheelbase goes out the window once the front tire truly goes flat, even if the tire stays between the rim and the road.
Remember, unlike with your single bike, your every movement during evasive manuevers on a tandem ripple back and forth with the stoker's counter movements and manifest themselves as lean-induced turning forces on the heavily loaded front wheel.
Even if you can get both feet off the pedals and down on the ground to work as stabilizers, unless the stoker can do likewise almost at the same time or keep their weight perfectly centered, the tandem will lean and turn the front wheel out from under you.
FWIW: We've ridden out two front flats at fairly high speeds on descents and in both cases we were able to go in a straight line and bring it to a stop without rolling the tire pr dropping the bike, albeit in one case travelling across the opposite lane just ahead of on-coming traffic and into a soft shoulder area/field. To say those were some rather intense moments would be an understatement. Flat protection is the one thing I miss about riding with glued-on tubies.
I believe they have some sort of belt that they call the "FPS" (Flat Protection System) which, apparently, works.
As far as the other forms of 'flat protection', our tires also have a hard rubber/plastic center strip embedded between the inner casing and tread compounds (i.e., SPL Sportex Protection Layer® – Polyamide strip under center tread) and they do seem to work, as evidenced by gashes discovered in the tread during the occasional pre or post ride tire checks. Their dissimilar color also makes for a nice tread-wear indicator that signals it's time for a new rear tire.
If you have a front end blow out on a high speed descent on either a tandem or a single you've got a problem. and obviously you've got the cooridination issue on the tandem, but I don't think your risk is substantially greater on the tandem.
"[QUOTE=Retro Grouch;6468644]What I don't like about Armadillos is the sidewalls are so stiff that they ride like an ox cart."
The folding armadillo tires have a more supple ride quality.
We've been in some pretty crazy situations with blowouts/flats/speed/hills combinations.
Credit goes to stoker Kay who does not loose her cool in tense situations.
Advised her a long time ago, stay loose and go with the flow.
Yeah, she's a GREAT stoker!
We run a Panaracer T Serv (urban/commuting). 350-400lb teams. 32c. Aramid bead 380g. We have had no problems in our broken glass, patched holes and scrap metal strune roadways. And we have a wide rim, fyi. Going to try some 28c's next.
Indy.
We ride a Cannondale tandem equipped with Bontrager Racelite tandem specific wheels. I run Continetal Gaterskins, 700-28 wire bead at 110 psi . Because during manufacturing tire beads can vary in tollerances, you need to pay attencion how easly the tires mounts on the rim. Larger diameter tires have tendency to blow off the rims with high psi (just try to inflate a mountain bike tire to 100 psi). If you can push the last three inches of bead on the rim with your hands, you have a loose fit. Because tandems put a huge load on tires, you want to run the mfg recomended tire pressure. You can get away with lower pressure in larger diameter tires. If your running rim brakes, the rims can heat up during long decents. This also can cause the tires to blow off the rims. Pumping the brakes and switching between the front and back can help prevent this. Happy Riding out there. JR
Schwalbe Big Apple 5000 miles (8000km) and no punctures or blow outs. Did some fast long descents in the Alps thankfully without mishap. would use them again. Had to change rear tyre at about 2000miles but on a fully laden tandem (for the most part) pulling a YAK. Tried to keep tyres at or below max inflation of 4-5 bar or 60 -70 psi. These slicks are quick.
Take an old tire, and cut out a 2" long section. This will make a tire boot that will fix virtually any blow out. It will bump with every rotation of the tire, but it will get you home.
Less severe blowouts, a dollar bill works nicely. (or a $20 if you like expensive components.)
1+ the dollar bill :love:
I am new to tandem riding, but have been riding road, hybrid and mtb for more years than I care to remember. Nothing is full proof, and I have had flats on them all, but I have never had a sidewall or tire gash that the old $1 bill did not get me home or to a rest stop.
I know it can happen, and I am sure I have now just jinks myself, but it really has helped me out when “good tires go bad”.
If you can push the last three inches of bead on the rim with your hands, you have a loose fit. ....JR
I mount all my tires by hand... even wire beaded 700X23. I think it is safer.
Just had a blowout (kaBOOM!) on our tandem today. 2+ inch gash in center of front tire.
A dollar bill (or a fiver or tenner) was not enough to bridge the gap properly. Anyhow, we were only 2 miles from our apt., so we walked.
Dissecting the tire at home, there was no flat protection strip and it looked as if it was a faulty/inadequate overlapping of the plys.
Good thing we bring a couple spares we we go away for the summer!
Pedal on TWOgether!
Rudy and Kay/zonatandem/ in cool Utah
I mount my tires by hand too. But the last three inches of bead should go on tight. It should take two thumbs and a lot of effort the get the bead on. If it just pops on with ease, it can pop off just as easly.
New to tandems and using regular tires for the added weight. My C'dale came with Vittoria Randonneur (sp?) 700x28 's . They sure looke like they might be pushing 700 x 22, but anyway I was curious what to run for air in them. The max PSI is 85 according to the tire, but obviously 85psi is WAY too low for a tandem. I had them up to 105 on the last ride and they road much better. Anyone else run these?
The front tire we 'Kaboomed' earlier this week was a Maxxis Detonnator. Have had about 3 tire failures (but not blowouts) with this model.
We usually buy a half dozen tires at a time and this was the last of the Detonnators.
Have also used the Maxxis Re-Fuse that has flat protection and had much better luck with them.
I mount my tires by hand too. But the last three inches of bead should go on tight. It should take two thumbs and a lot of effort the get the bead on. If it just pops on with ease, it can pop off just as easly.
This hasn't been my experience. I think it also depends on the depth of the rim. I have had tight tires that popped off (Continental Ultra 2000). Our current tires are fairly easy to go on and they have never popped off( Vredestein Fortezza).
So what's the consensus on a strategy for surviving a front wheel flat on a high speed descent? Never had the "pleasure" although my instinct would be to have my stoker stay clipped and leave the "driving" to me.
Our used tandem came with Conti Gatorskins. They rode OK, but were getting thin so we replaced them with 23c Fortezza Tricomps at 140 lbs. Same tires I run on my single, so very convenient that way. I got the idea from a very fast and heavier tandem team that I ride with on my single. Works great. Nice road feel, corners well, fast, good wear, rear tire looks about right, not at all harsh riding IMO. Have a puncture resistant belt, but of course you can get sidewall cuts with any tire. Easy to carry a spare one of these. We're a 300 lb. team.
New to tandems and using regular tires for the added weight. My C'dale came with Vittoria Randonneur (sp?) 700x28 's . They sure looke like they might be pushing 700 x 22, but anyway I was curious what to run for air in them. The max PSI is 85 according to the tire, but obviously 85psi is WAY too low for a tandem. I had them up to 105 on the last ride and they road much better. Anyone else run these?
Are you saying that in general we should be over-inflating the tires on our tandem? By how much?
Are you saying that in general we should be over-inflating the tires on our tandem? By how much?
Not sure if I should be or not, but it sure rides a lot better with over inflated tires. When I was running them at 85 they were really squishy on the road and you could hear it as they were flattening out on the contact patch. I'm running them right around 100-105 psi now and they are much better. We are a 310lb. team. There is a dramatic performance increase at higher pressure on the tandem it seems. These Randonneur tires are heavy and even though they say 700x28 they are the same width as my Fortezza's that are 700x23 on my single.
I've tend to do the opposite on my single road bike. I am running Fortezza's on it and they are rated to 120psi. I usually run 100psi on those for comfort, but they are still plenty fast at that pressure.
Not sure what is right, but so par 100psi seems like a better choice.
Our Co-Mo Speedster came with 700c x 28mm Conti Gatorskins. I changed to 25mm Vredstein Fortezzas, which had a more supple ride and seemed a bit faster. Then when I bought another 6 tires and had serious quality issues (bubbles, tread separation, premature sidewall blowouts), I decided to give up on Vreds. I had been using 700c x 23mm Conti Gran Prix 4000s on my single with great results so I decided to trade the Vreds for 700c x 25 Conti Gran Prix 4000 for the tandem. I am extremely pleased with the ride, flat resistance and wear that we are getting on the GP 4000s, both on the single and tandem.
I have been using folding tires on the tandem for years without any problems resulting from loose beads. I don't see why a wire bead would be superior for tire retention. And I install all my tires by hand only.
We also exceed the recommended max pressure on our tandem tires. We usually run about 125 psi on front and rear. Team weight (not including bike) is around 315 lbs.
Here is my Panaracer Tserv splitting. About 1YR / 1K miles old. Front and rear both sides, all the way around.
73490
Here is my Panaracer Tserv splitting. About 1YR / 1K miles old. Front and rear both sides, all the way around.
Can you describe the inflation history of this tire? Did it get fully deflated much? What environment is it stored in? Any flats during that time? This looks like inflation fatigue coupled with some kind of chemical or uv hardening.
350 lb team. 110 psi, check 95% of time before rides. Stored in a cool PNW garage hung from the ceiling. Not an expert on this at all, but I would guess it is from the rims getting hot through braking.
350 lb team. 110 psi, check 95% of time before rides. Stored in a cool PNW garage hung from the ceiling. Not an expert on this at all, but I would guess it is from the rims getting hot through braking.
350 lb team. 110 psi, check 95% of time before rides. Stored in a cool Pac NW garage hung from the ceiling. Not an expert on this at all, but I would guess it is from the rims getting hot through braking.
A blow out on a front wheel at high speed?, Well my suggeston is JUMP OFF... your gonna die anyways
I have been using folding tires on the tandem for years without any problems resulting from loose beads. I don't see why a wire bead would be superior for tire retention. And I install all my tires by hand only.
I prodded the individual that gave me the information on this more and they indicated that it was more likely for the tire to come off and wind up on the wheel in a blow out situation and said that they had witnessed it at least once. I don't know if your tire is that flat if it makes all that much of a difference or not. I think that the hilly terrain people tend to ride where I live doesn't help.
I install all my tires by hand but I have noticed that I need one tire lever to remove the Conti steel beaded tires we are running now. I can pull a Conti 4000 off the rim without a lever as long as the tire has been completely deflated.
...they indicated that it was more likely for the tire to come off and wind up on the wheel in a blow out situation and said that they had witnessed it at least once...
Yes, I'm sure anyone can witness any occurence "at least once". The problem is without a controlled test of the same situation occurring with a wire beaded tire, preferrably several times to establish a consistant outcome, the observance is inconclusive.
The sport of bicycling is rife with "urban legends". By that I mean any so-called expert (the mechanic at the LBS who's been wrenching for two years, the guy or gal in the club that's been riding for decades, etc.) can make a statement and it is passed along from rider to rider as if it were gospel, regardless of whether the statement passes any form or scientific scrutiny. Sometimes what seems logical to the less informed rider is just bad science. I don't mean this as a put-down to non-technical types, because I'm sure most of this spreading of bike mythology is well-intentioned.
The fact is that Kevlar 49 has 60% of the modulus of steel and Kevlar 149 has 95% the modulus of steel and either can provide the same resistance to stretching as a steel cable by increasing the cross sectional area accordingly. I stand with my original statement: "...I don't see why a wire bead would be superior for tire retention...".
I like Kevlar beaded tires, not so much for the lighter weight, but primarily because they fold up to a much smaller size, which makes carrying them in a pack as a spare much more practical.
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