Thread: Tubeless Tires
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Old August 19th 18, 03:27 PM posted to rec.bicycles.tech
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Default Tubeless Tires

On Saturday, August 18, 2018 at 3:52:42 PM UTC-7, jbeattie wrote:
On Saturday, August 18, 2018 at 2:41:38 PM UTC-7, wrote:
On Wednesday, July 25, 2018 at 5:39:51 PM UTC-7, wrote:
A couple of months ago I was struck by a car that decided four way stop intersections were not what they meant. I had come to a complete stop and allowed ALL of the traffic to pass and started across. I got 2/3eds of the way across and the woman who had been behind a pickup I let pass rolled the stop sign and accelerated directly into me. She was obviously distracted but the old bat might have been having her first clear shot at a bike for all I know.

In any case perhaps I should start from the beginning - back around 2008 I bought a new Time VX Elite carbon fiber bike. With the normal 120 psi 23 mm tires it was completely un-ridable. It was so stiff it would hammer your balls through your skull on the first bump. So it went up on the shelf.. I removed the components and used them elsewhere and that frame just sat there. Anyway I decided to put it back together and since the latest fad is fat tires I put 28 mm Michelin Krylon Endurance on them. What an F-ING difference! With the fat tires it is one of the best rides I've ever had.

My Pinarello Stelvio was the one I was riding when I was hit and while the frame and fork came though OK every component on the bike was broken.

I had Campy Scirroco CX wheels on it and I discovered that I HATE aero wheels with a passion. Since her insurance company was paying for it I bought a set of Fulcrum Racing 3 wheels that were last year's and on clearance. When they arrived they were already set up for Tubeless. Well, I had been wanting to try that as well.


The older steel bikes won't fit fat tires so the largest that would fit are 25's. I installed the tires on the wheels. I had bought 4 ounce bottle of Orange sealant which was the best in the tests I read.


Now the tires will not go onto the rims because they are a bit tight. So first I put the filler at the bottom and using a Park Valve Tool I removed the valve head. Pumped in 2 ounces of Orange then turned the wheel perhaps 1/8th of a turn so that when you release the squeeze bottle it doesn't suck the sealant back in. Then I hit it with a CO2 cartridge. POP!!! it was on and I rotated the wheel while laying it on one side and then the other since initial leaks are from the tire and rim not being a perfect fit.


Every morning I had to pump the tires up until I finally took it for a ride and that fit the tires well onto the rim and the bumps packed sealant into any voids.


Now the tires with tubes would normally run around 110 lbs and be not very easy riding. But now I ride between 60 and 80 psi (letting the pressure go down over a week before refilling).

The ride is exceptional. With the higher pressure they are sort of bouncy so fast downhills can be scary. With the lower pressure the rolling resistance doesn't seem to increase detectably. Riding with guys with the high pressure tube tires I find myself coasting while they are pedaling.

Not to mention they cannot get a pinch flat and with the sealant they cannot get flats. So I can leave that damn 2 lb flat kit at home and just take a multitool and a CO2 cartridge and filler just in case I get a large enough hole that the tire gets too soft before sealing. And I doubt I'll ever need that.

So if you've had any questions about how tubeless works I am quite satisfied with it after a couple of months.

Now I ride sport bikes and I don't know that this would be a good idea for 32 mm commuter tires. Though probably, because they talk about using them for CX tires which have a lot of pinch flat problems. But these normally run higher pressures than you would with a tube in it. There's always the possibility of it blowing the tire off of the rim unless you're using Mavic tires and rims specifically designed to work together tubeless. As far as I know Mavic are the only people to have "systems" designed.


I again rode my tubeless which for the Pinarello are 25 mm. Running at 80 psi they actually felt a little over-inflated since there was a little too much "bounce" to them. I am 6'4" and right now weigh 181 lbs. The bike is 22 lbs complete with a very small seat pack that contains only a CO2 inflator and cartridge.

The rougher the surface the lower the pressure you should run. On a tubeless the limit is when the tire begins to "squirm" or roll around and threaten to slip off of the rim. On tube tires the threat of a pinch flat is there even at full pressure if you hit a sharp bump such as a missing utility cover which around here can be only 6" across.

In any case, the other guys were riding high pressure 23's with tubes in them. I was taking about 2 pedal strokes for every 3 they were and I was continually having to put the brakes on as I kept coasting up on them because the rolling resistance was so much less. If I take the lead and just pedal easy I drop them. But they are old farts like me so that is no surprise. This is why I ride lantern rouge.


I have never used tubeless, so no comment there, but I think you're just faster than your friends, and tires probably have very little to do with the relative speed difference. Tell us how the tubeless compare to your prior light tube/light clinchers.

I'm working through my back-stock of 23mm Pro4s (I'm now using 25s on the fast bike) and have one of those on my rear wheel. I got a flat today and popped in a tube and hit it with a CO2 inflator -- 16g, and man, that really gets it rock hard, for better or worse. I'm pretty sure the flat was from a rock strike, but it wasn't a big blow-out. Anyway, sealant probably would have taken care of it, and flying down a hill with bad surface, a rock hard 23mm tire doesn't inspire confidence.

I did miss my discs a little. I had to bail out onto a gravel shoulder when a f****** meat-head in a PU pulling a boat went way over the center line and into my lane on a descent. This one: https://www.youtube.com/watch?v=-NPqQptjbF0 -- except sunny and dry. I stopped before going down a ravine, which was good.

And since I'm telling stories, there was a three or so mile gravel climb, which also sucks on narrow tires, and to add insult to injury, I ended up in a pack of gravel bikers -- more ad hoc Portland bike racing. I've got some OE wheels that came on my Emonda that I might set up as tubeless just to try the goop experience.

-- Jay Beattie.


Well, I am faster than they are but they didn't start out slow yesterday. In the second mile they were doing 20 mph on the flats and that isn't like them. Especially since the guy leading was on knobbies.

The trouble is that old guys can tire themselves out fast and we stopped for coffee at the half way mark and after that they were dead slow. So the first half of the 25 miler was at record speed and the apple juice stop at the end had these guys looking like they are going to keel over. And one of them had another 7 miles to ride home. At that point he could barely hold 10 mph so my low rolling resistance really showed up and I was pedaling one stroke and then coooooaaaaaaaasssssssssttttttttt.

The problem with Portland shows plainly in your video - it's always wet all the time. I had that problem in Seattle - the dry days were wet.

On the Time Edge I'm trying to sell I could NOT ride it with hard 23's. But with 28's it really rides like a very good bike. That was the largest change I've ever seen in the ride of a bike. The 28's would fit on that bike but most modern bikes won't mount tires that large. On my old Basso I fit the Pro4 Endurance 25's. They are still tube tires since they're worn and I would wait for new one's.

I note that Vittoria now has a tire that uses Graphene in the cord so I bought a set to try. That is the strongest material known to man presently so they ought to be light. My only fear is that they will have gone too far trying to make it light and reduced the tread depth to so thin that they will wear out in a ride.

Oh well, the wheels and handlebars and compact front derailleur aren't due till the end of the month so I have to maintain patience. But rough estimates are that the finished bike will be about 16 lbs. My younger brother's Giant TCR-0 weighs that and every time I lift it up I'm amazed. So I'll get to try something that light out.
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