Catastrophic blowout, new lessons learned

[StmbtDave]

I've never liked the idea of tubeless bike tyres. There's dozens of sharp spokes on a rim, and it only takes one to break and create havoc. True, this could happen w/ a tubed tyre too, but bike rims flex, they're thin walled aluminum, and their narrow design means there isn't much to keep something like this from happening on what sounds like a normal ride and it blew out just because.

When you put a tube in there, the forces are distributed equally because between the air (which is hard at high pressures) there is the rubber tube pressing against the rim and also against the inside of the tyre. It balances the pressures out radially because the more surfaces that are involved, the more the forces are spread out. There is a little give and take. With no tube, forces are acting directly on the tyre itself, hard air against hard rim, and the weakest spot is always going to be the most dangerous and least forgiving spot, right where the tyre clinches onto the rim. High air pressure, aluminum rims that flex especially during cornering, shallow grooves for tyre clinching, no thank you.

I have to disagree. There are no differences between tubed and tubeless as far as the forces are concerned. The air doesn't care if there is a tube or not. Everyone is making too big of a deal of this one example. Blowouts are just as common with tubed tires with the same results. As mentioned, the key is having both tubeless rated rims as well as tires.

I have been running tubeless for thousands of miles with no problems. I ride in the Arizona desert and tubeless with fresh sealant is the only way to go. I am passing my replaced ebike down to my son. He doesn't want to mess with having to refresh sealant so he had me install tubes. I found 4 cactus thorns in one tire and the tire was still holding air (50 lbs). Had there been a tube installed, the first poke of a thorn would have meant a flat tire.

 

[Sierratim]

I have to disagree. There are no differences between tubed and tubeless as far as the forces are concerned. The air doesn't care if there is a tube or not. Everyone is making too big of a deal of this one example. Blowouts are just as common with tubed tires with the same results. As mentioned, the key is having both tubeless rated rims as well as tires.

I have been running tubeless for thousands of miles with no problems. I ride in the Arizona desert and tubeless with fresh sealant is the only way to go. I am passing my replaced ebike down to my son. He doesn't want to mess with having to refresh sealant so he had me install tubes. I found 4 cactus thorns in one tire and the tire was still holding air (50 lbs). Had there been a tube installed, the first poke of a thorn would have meant a flat tire.

Tubeless is a proven tech, but different than tubed setups. My sons have ridden tubeless for years and swear by them, but they're into MTBs. I don't want the hassle of the extra pieces and parts for tubeless and am OK with the occasional trail side repair. Good tires do help minimize this. I run thorn strips in our mechanicals. Neither of us has had a flat in several years, even with fairly run of the mill tires.

 

[linklemming]

I have to disagree. There are no differences between tubed and tubeless as far as the forces are concerned. The air doesn't care if there is a tube or not. Everyone is making too big of a deal of this one example. Blowouts are just as common with tubed tires with the same results. As mentioned, the key is having both tubeless rated rims as well as tires.

I have been running tubeless for thousands of miles with no problems. I ride in the Arizona desert and tubeless with fresh sealant is the only way to go. I am passing my replaced ebike down to my son. He doesn't want to mess with having to refresh sealant so he had me install tubes. I found 4 cactus thorns in one tire and the tire was still holding air (50 lbs). Had there been a tube installed, the first poke of a thorn would have meant a flat tire.

You could try putting sealant in the tubes. I have been doing this for over 10 years without any flats. My current bikes all have goathead thorns in them.

FWIW, I ran tubeless for years. Just not worth the hassle for me.

 

[Sierratim]

You could try putting sealant in the tubes. I have been doing this for over 10 years without any flats. My current bikes all have goathead thorns in them.

FWIW, I ran tubeless for years. Just not worth the hassle for me.

I agree.

 

[DanInStPete]

I'm certainly not going to crusade against tubeless. I posted this because though I've had many flats in my lifetime I have never blown a tire completely off the rim. So on this bike, with these rims, after that explosion, I'm more comfortable now with the ebike 50 Contis and tubes (though it doesn't look as cool as the gumwall Gravel Kings )

I started with those tires because I wanted to ride some gravel and light trails, which I did. Now that I have a new eMTB the Vado is purely for pavement.

I will keep my Haibike tubeless. I just mounted these 3" monsters tubeless last week - a first try at doing it myself, with a hand pump. Worked out perfectly. Running 20lbs in the back and 18 lbs in the front (I weigh 240)

 

[FlatSix911]

You could try putting sealant in the tubes. I have been doing this for over 10 years without any flats.

My current bikes all have goat head thorns in them. FWIW, I ran tubeless for years. Just not worth the hassle for me.

I agree... If you go with inner tubes, try the ones that have sealant inside. They seem to last forever if they are pre-slimed.

 

[PDXzap]

Last summer I picked up a little used Diamondback Edgewood. At that point I hadn't ridden much for about 5 years, the Edgewood was a large bike and my first 700c. Honestly, most of the bikes I've owned have probably been a little too small for me but I managed... so I spent a few days learning, cleaning, tuning the bike to my liking and putting a couple of miles on.

I needed some hardware for a project and decided the bike would be perfect for the round trip of about 10 miles. I gave the bike a "once over", aired up the tires to a few pounds under the max psi and headed out. It didn't take but a minute or two to remember why I enjoyed riding bikes so much and even though I was feeling more comfortable with this new bike I was still taking things a little cautiously.
The route had a fairly steep down hill within a block and from there it was a steady climb for a mile followed by a mile long down hill. I already knew that this bike could pick up speed easily and I'd never ridden a bike on this stretch of road so I was riding the brakes a little as I headed down.

Here's a profile of that road:


At about a half a mile down that slope I began to hear a slight tick and slowed down and attempted to locate where the sound was coming from but couldn't and I came to a stop at the stop sign and still couldn't see anything amiss. At the bottom of that slope the road makes a pretty tight right turn onto a bridge. The speed limit is 25 mph a little ways before the stop sign and I was probably doing close to that not long after the sign and as I started applying the brakes and heading into the turn I could hear the tick start getting louder. As I started applying more brake, because of the louder tick, I heard a loud bang, about as loud as a .38 caliber and at the same instance felt the front of the bike drop and felt the steering go wonky.

I don't know if instinct kicked in or what but I managed to stop. I was riding on the (small) shoulder and in the short time I was wrestling the steering and got to a stop I was in the middle of the road and I just sat there for a few seconds "shell shocked". Luckily there were no cars around and I finally gathered up the sense to move over to the edge of the road and start heading for home carrying the bike with the front wheel off the ground. A guy I had passed a few minutes before was still walking down the hill and looked at me and my bike and asked if it was my tire that made the sound, he said he it sounded like someone was maybe shooting a gun into the water off the bridge.

The tire casing ripped apart from the bead and the increasingly loud tick I heard had been the growing bulge on the front tire hitting part of the rim brakes and once the tube bulged out it was done for. I was lucky!

 

[Stefan Mikes]

Just name one benefit from running the tubeless except minimal weight saving.

 

[linklemming]

Just name one benefit from running the tubeless except minimal weight saving.

The ability to run lower pressures without pinch flats is often quoted

After many years of running tubeless on my MTBs(with many issues), I started running tubes with sealant (before ebiking). At a point, I decided to go back to tubeless(with sealant) for my ebiking. I did notice better/more compliance but the ability to run lower tire pressures just made the tires squirm more and they were much less predictable. They also lost LOTS of air between rides. So I switched back to sealant in the tubes on my ebikes

But if running tubeless works for you, then embrace it. I use it on my newly aquired FS acoustic MTB (for weight savings)

The abilty to patch a flat with a bacon strip or one of the new stans plugs would be a HUGE benefit (and why I decided to retry it). That being said, I havnt had a flat since using stans selant in tubes over 10 years ago. Why solve a problem that doesnt exist (for me)

 

[DaveMatthews]

Just name one benefit from running the tubeless except minimal weight saving.

I was having flats from blackberry thorns around here. Got sick of that routine and went tubeless with Stans sealant.
No flats since. Upon tire inspection I have pulled numerous thorns out, no problem.

 

[Stefan Mikes]

What is the difference between a tubeless tyre filled with a sealant and the inner tube filled with a sealant?

 

[Sierratim]

What is the difference between a tubeless tyre filled with a sealant and the inner tube filled with a sealant?

A bit more weight with the inner tube. Sould be able to run the tubeless tire at lower pressures without getting pinch flats in the tube. Not sure the sealant filled tube could seal the twin holes caused by the lower pressure pinch flats.

Slime branded inner tubes come with sealant pre-installed though it doesn't look like they offer these tubes in the wider widths; https://shop.slime.com/collections/self-sealing-bicycle-tubes . Of course the tubes are heavier and have more bulk. They also offer various sizes of tube sealant - up to 5 gallons for all you aggressive riders - https://shop.slime.com/collections/tube-sealant-and-tubes . They also offer the pieces and parts to convert to tubeless.

Stans also offers tube sealant; https://www.notubes.com/shop/tubeless/sealant , as well as conversions to tubeless. Their products are quite popular with MTBers.

 

[StmbtDave]

What is the difference between a tubeless tyre filled with a sealant and the inner tube filled with a sealant?

A tubeless tire is rigid so any small puncture can easily be sealed by the sealant. An inner tube is extremely flexible as you see when you inflate one outside the tire. Tubes move and flex even when inside a tire. This is why many of us powder tubes before installation. Even a small puncture in a tube is difficult to seal and the success rate is relatively low (per my LBS). If enough sealant leaks out of the tube, it may seal the puncture in the tire itself, so you're back to sealing a tubeless tire (with a tube).

 

[Stefan Mikes]

Unless that is the Michelin Protex Max inner tube perhaps?

 

[Sierratim]

A tubeless tire is rigid so any small puncture can easily be sealed by the sealant. An inner tube is extremely flexible as you see when you inflate one outside the tire. Tubes move and flex even when inside a tire. This is why many of us powder tubes before installation. Even a small puncture in a tube is difficult to seal and the success rate is relatively low (per my LBS). If enough sealant leaks out of the tube, it may seal the puncture in the tire itself, so you're back to sealing a tubeless tire (with a tube).

Powdering your tubes also keeps them from 'vulcanizing' to the tire's inner walls. This is more common in hotter climes esp when the tubes are left installed for some years, i.e. no flat repairs. My oldest son had this problem. He finally had a flat but couldn't get the tube out. It had sealed to the tire. He had to scrap both tire and tube. I use an off brand (i.e. cheap) baby powder on all my tubes. The spare I carry on the bike is pre-powdered in a zip lock bag. I also powder the inner surface of the tire when fixing a flat in the home shop - helps make sure I didn't miss any tiny things poking through the tire.

 

[indianajo]

I think if you're doing a long distance ride, tubeless would be much easier to fix your flat tire.

I just took off two kenda knobbies with >2000 miles on them. No flats. No slime. Yes tubes. Reused the tubes. You going to ride more than 2000 miles tomorrow?
I can insert a new tube in 40 minutes, even if I have to pull 60 lb groceries out of the bag. Per PDSzap's experienced, learned not to use good looking tires over 5 years old out on the road. Sidewall blowout, cord failure. I can't carry a spare tire; had to push it to destination.

 

[Smong]

When I was road racing we had a controlled start from the top of a ski area to a few miles down from the steepest part. The pace car kept to 25 mph and about 125 of us rode behind it. By the time we got to the bottom it sounded like we were in a firefight with all the tire explosions and lots of sick sounding crashes all around. Of course many of us were running 20mm tires at 150 psi and the rim heat from braking did a number on them. Disc brakes take care of that issue nowdays. To be young and crazy again...I hit 62 mph on that same hill without a pace car!!

 

[DanInStPete]

What I meant was that, it is easier to fix flat on the road.
If I were to do a roadside repair, tubeless is much easier.

All you need is this.

Although this one is for motorcycle, I believe they have a very similar kit for bicycles as well.

On the other hand, if you were to replace a tube, it takes a lot more time and you will need to carry more tool.

Even people on motorcycles (dual purpose bikes, dirt bikes, adventure bikes) carry tubes, tire irons, air pump or CO2, and all the other tool to replace a tube.

I just bought a smaller version of this for my eMTB. I carry a tube also.

 

[Sierratim]

Tubeless patch kits are small, fast and convenient, just like their big brothers for auto use. My sons carry them. They also won't leave home without a tube and tire levers just in case they get a slash, or like the first post in this thread, a blow out.

 

[Smong]

When I was road racing we had a controlled start from the top of a ski area to a few miles down from the steepest part. The pace car kept to 25 mph and about 125 of us rode behind it. By the bottom of the steepest part it sounded like a gun battle, all of the braking caused the rims to heat up and the tubulars blew first then some of the tube tires. My 20mm wide tires at 150 psi held up fine and I hit 62 mph going down the hill without the pace car. Oh to be young and foolish again...and have disc brakes.