tubeless-spare tube for flats

[gabkr]

I run Hutchinson Atoms w/ Dura Ace 7850 c24-TL wheels,dry(no sealant).......I have not had a flat,and carry a Hutchinson patch kit,and some pre-glued patches with me. Do I need to carry a spare tube,and if so,should I use a smaller than normal size? (heard about the mounting difficulties) I have some Fusion3 tires on hand as a back-up,no stores around me keep them in stock.

Like the ride,and other than leaking down pretty quick,have not had any problems. I guess I need to practice mounting/dissmounting at home,before I get caught on the road. Thanks, any help or hints appreciated.

[well biked]

I've been running mountain bikes with tubeless tires for about ten years, and have run road tubeless for about six months. I've never not used liquid sealant with tubeless, and I've always carried a spare tube. In this whole time, I've had to fix a flat during a ride, while running tubeless with sealant, a grand total of one time. It was on a mountain bike ride, and I should have known better; the tire had come off the rim during setup and had shown signs of a damaged bead. Sure enough, way out in the middle of nowhere the tire blew off the rim, sounding like a gunshot as it did. But it was no big deal, other than shaking me up a little; I had a tube and supplies to get the tire inflated again. I used very low pressure, and cautiously rode out of the woods on the damaged tire. Glad I had the tube, it would have been a long walk without it. Bottom line: carry a tube, no doubt about it.

A note about sealant and tubeless: the sealant is a significant part in getting the most out of running tubeless, IMO. For road tubeless, IMO, the main advantages are the ability to run lower pressures for better ride quality without worrying about pinch flats, and having the liquid sealant in the tubeless tire to greatly reduce flats from punctures. To not use sealant takes a big part of the advantage away.

I have communicated with Shimano about using liquid sealant in their road tubeless wheelsets (Dura Ace and Ultegra), since our shop is a Shimano dealer and this question has come up, and their official line is to not do it, there are concerns about corrosion. They say the warranty on the wheels will be voided if there are any problems relating to the use of sealant.

I'm a huge fan of Stan's Notubes products, and have built both road and mountain wheelsets for my own bikes using Stan's tubeless ready rims. We also sell a lot of their products. I'm sure there are cases of corrosion damage with various liquid sealants, but I can say I've never had a problem and find the benefits of using Stan's sealant too good to pass up. YMMV.

[Vince Canepa]

I have experienced the corrosion problem with my Dura-Ace wheels. After one year the rims were so corroded they would not hold air and had to be replaced. Shimano would not warranty them because sealant was used. Interestingly, the Dura-Ace wheel instructions specifically warn against using "alkaline" sealants or it will cause corrosion. The Ultegra tubeless wheels do not carry such a warning (at least I could not find it). The sealant used was Caffee latex. The new rims were $650 (parts only) so it is not a small concern. I don't use sealant anymore and carry a standard size tube as a spare. Also, mine don't bleed done very fast; hardly more than my wife's bike with standard clinchers. It seems a bit of a hassle, but when I change to my spare wheels with standard clinchers (Vittoria Open Corsa Evo) the difference in ride quality is VERY noticeable; the tubeless ride so much smoother it is hard to go back.

[Tuc]

My LBS will not use sealant on tubular, they say it wrecks the rims and is not worth it because when it seals a pinch flat it makes a bulge between the rim and the tire. These explanations above in the thread are making some sense, but I wonder if there are other non alkaline sealants available? Sealant has to dissolve or "melt" the rubber compound around the leak to work, so I suppose most anything corrosive enough to do that will eat aluminum rims too. Are any sealants approved by Shimano or any of the major wheel manufacturers? I mean, the glue that holds the tubular on doesn't necessary wreck the rims, what is it made of?

[well biked]

I have experienced the corrosion problem with my Dura-Ace wheels. After one year the rims were so corroded they would not hold air and had to be replaced.

Good to know. We're not recommending any Shimano tubeless wheels be run with sealant because of Shimano's position on it. Based on your experience, their concerns must be valid. I will say it's surprising to me, because I've never had the sealant damage my rims on mountain bikes, with some having sealant in them for several years. Mavic rims in this case, I've only run the Stan's Notubes rims for a relatively short time period, but I'd be surprised if the sealant damages those rims, either.

[well biked]

Sealant has to dissolve or "melt" the rubber compound around the leak to work, so I suppose most anything corrosive enough to do that will eat aluminum rims too.

No, that's not correct. The sealant simply has enough solids in it to seal small punctures, with the help of the air pressure in the tire.

[well biked]

Are any sealants approved by Shimano or any of the major wheel manufacturers?

No sealants are approved according to my communication with them.

[pmt]

I run Hutchinson Atoms w/ Dura Ace 7850 c24-TL wheels,dry(no sealant)

You should really just save those for racing on smooth roads; for training, use Fusion3 or better yet, Intensive.

I have not had a flat,and carry a Hutchinson patch kit,and some pre-glued patches with me. Do I need to carry a spare tube,and if so,should I use a smaller than normal size?

It's way easier to get a tube in if you use small 18c tubes.

I guess I need to practice mounting/dismounting at home,before I get caught on the road.

You should already have practiced that many, many times before riding them. They're not the same as regular clinchers, so you really want to practice over and over before doing it on the road under pressure. If you ride in the rain, practice out in the rain as well (or setup the lawn sprinkler).

[gabkr]

Thanks PMT.....will get an 18c tube and try out the Fusion 3's

[gabkr]

That is a 18 combination tube...like 700x18-23 ...right?

[jolly_ross]

Do I need to carry a spare tube,and if so,should I use a smaller than normal size? (heard about the mounting difficulties)

I'm guessing the mounting difficulties apply to tires, not the tube. I certainly had a horrible battle getting some tires onto some new tubeless rims a couple of days ago (solution, get a volunteer - it needs 3 hands: 2 to do the hand over hand thing with 2 tire levers - and 1 to stop the point where you first mounted the tire from unmounting and running away from you around the rim). Anyhow - carry the correct sized tube, hopefully your tire bead will get stretched to the right size and, if necessary, roadside demounting/remounting won't be too hard.

You need a tube because, although quite rare, you can get cuts too big for the sealant to heal up. One thing to watch out for: before you put in an emergency tube you must carefully go around the inside of the tire. There will likely be a few thorns and flints which have got through the tire, been sealed by the sealant and effectively glued into place waiting to puncture a tube when you put it in. I learnt this the hard way.

The tubed/tubeless debate rumbles on in my cycling group. Like chainlube or wearing helmets it's a quasi-religious issue and utterly pointless trying to change people's minds. Fwiw heres my 2c: I use tubeless - I believe that I end up spending pretty much the same amount of time frigging with my tires, the difference is that I get to choose when I do it. I mount and top up my tubeless tires in the comfort of my shed, I don't fix flats out squatting by the bike in the rain. You should do what you want.

[pmt]

You need a tube because, although quite rare, you can get cuts too big for the sealant to heal up.

Well, no, you don't *need* a tube. I simply patch the tire right on the side of the road and go when I've flatted. There was one time when the heat index was 110F and the patch wouldn't stick, so in that case I had to put a tube in.

The tubed/tubeless debate rumbles on in my cycling group. Like chainlube or wearing helmets it's a quasi-religious issue and utterly pointless trying to change people's minds.

The naysayers generally haven't ever used Road Tubeless so they have no credibility when writing about it. They're also the people who pooh-poohed things like clip-on aerobars, clipless pedals, and indexed shifting.