rpenmanparker 

Sealant seals holes, not intact surfaces. If you are going to make a claim, you should have an explanation for it. Besides there are other possible reasons for the slower air loss. If your tube is heavier than mine, your rate of air loss will be lower.

rubiksoval

It doesn't sound like you understand why a tube loses air in the first place.

Your journey to enlightenment commences. Good luck.

rpenmanparker 

You have no idea what or whom you are talking about. Give it up or look and sound even more foolish than you do already.

himespau 

Holy ****, that's the first time I've actually laughed out loud at something on the internet in a long time.

BillyD

You two guys . . . you know who I mean . . . it wouldn't hurt to calm down a little.

November Dave

Latex tubes can be more finicky to install than butyl tubes but if you trap either between the tire and rim it will fail.

Latex tubes leak air at a measured and well established rate of between .5 and 1 psi per hour.

Sealant installed in a latex tube will cut the rate of air leakage down to at least the level of a standard butyl tube, if not better. This has been proven conclusively. I have a latex tube in use right now in which I installed sealant following a very small puncture, and this tube leaks air at a rate of less than 10psi per week. Many non-tubeless mountain bike tires will aggressively leak air through the sidewalls before sealant is installed, which stops completely following sealant installation. My mountain bike tires have the same psi right now as they did when I last rode them 11 days ago. That phenomenon is settled, it is not in debate.

Latex tubes have a consistently measured advantage of roughly 3w per tire over standard butyl tubes. Lightweight butyl tubes (which leak air, btw) split the difference between the two.

MSRP for a latex tube is generally ~$20, lightweight butyl is ~$10, standard butyl is ~$8. Put in one perspective, a 6w gain for ~$24, or ~$4/w, is about the cheapest performance gain you can make on a bike. Whether that is relevant to you is entirely yours to decide.

I personally find a readily identifiable compliance/suppleness benefit when using latex versus either standard or lightweight butyl. My acuity with such things seems to vary with different things, so I would not necessarily call myself an across the board highly sensitive person. You may or may not perceive this.

That's basically it.

merlinextraligh

This. the race wheels for the TT bike have latex tubes. Data would indicate a 1-3 watt per wheel savings. 2-6 watts for an extra $10 or so, and a very little bit of hassle, its worth it.

Not worth it for everyday riding IMHO.

wphamilton

That is sensible. But on the other hand, whatever is in the saddle bag is a permanent fixture of the bike for all practical purposes. And it's almost never used compared to functioning parts. If I'm concerned about weight on the bike, I think it's an even higher priority in the bag and I want the lightest possible contents there, even if they don't work as well. Since they're basically not used. So I think I'd want the latex tube in the saddle bag, and tubes that hold air inside the tires.

rubiksoval

Saddle bags and performance don't go in the same sentence for me. Saddle bag always comes off when I want to go fast.

If you're only doing club rides and the like and are always carrying a saddle bag, then I wouldn't even worry with latex. Hard to justify.

I only use latex in my race wheels, and my race wheels are only on my bike during race season, and then only because it's too much of a hassle to swap brake pads every week. If I have a long stretch without racing, I put back on the aluminum wheels with butyl tubes.

rubiksoval

Whom? Is latex a person?

When you regress to insults because you can't actually offer a rebuttal, well... You have fun out there, bud.

Ilbiker

OP here. Lots of good info and interesting points of view. Right now, for my situation, I'm opting for overall reliability and sticking with butyl during my training and racing. I have one bike and one wheel set. A couple of watts per wheel isn't super important since I have an endurance geometry based bike. I'm trying out racing in the form of duathlons. I'm already a competitive runner. If I stick with this I can see a tri bike sometime in the next year. I can see its advantages and would want to eek out all possible performance and latex is a cheap way to do so.

My new tires get delivered today so I'm curious to see what improvements they have over the original stock rubber. But, dang, you guys really got me curious to try latex. I like experimenting and tinkering, that was a way of life when I flew RC planes.

wphamilton

How long does one of your races last? It seems to me that the whole discussion of the drawbacks of latex is moot, if the only concern is performance at an event for an hour or two.

I'd want every edge I could get in a race, even if it meant strapping CO2 to the hub with an electronic valve. I could see wanting latex tubes in that case.

merlinextraligh

its more than 10ths of seconds.

Take the top end of the range, 3 watts per tire, total 6 watts, and for a cyclist doing a 40km TT in an hour,
Latex tubes would save 37 seconds. Even if its just one watt per wheel, its still a 9 second difference.

That's a pretty significant difference for a TT. And it comes very cheap.

Just because you're not paid to race, doesn't mean you shouldn't race to win, and make equipment choices that help that effort.

merlinextraligh

Unless you're doing something like Paris brest Paris, the rate of pressure loss is not going to be enough to affect performance in the event.

IME, 10%, or less, air pressure loss in 24 hours is typical with latex tubes.

People have been doing long stages of the Tour de France for a very long time on latex tubed tubulars, without pressure loss being an issue.

Ilbiker

Of all the folks I know that race, whether running, biking or swimming, none are paid to do so. Some are very competitive and have the necessary goodies to give them any and all advantages. Latex tubes would be a no brainer on a TT bike. Hell, a pair of my racing shoes are "slightly" more expensive than a pair of latex tubes.

rubiksoval

Races vary a lot, from an hour long crit to a 4.5 hour long road race.

Definitely worth it in races, in my opinion, but you're also not dealing with changing out flats. You just take a new wheel.

I run sealant in my latex tubes, too, so a little added protection with no rolling resistance penalties or the like.

RChung

This is the post to pay attention to.

Putting sealant into a latex tube does reduce pressure loss, but you can only do this for latex tubes that have valves with removable cores. Mine don't so I just pump them up before rides.

redlude97

you can add sealant by removing the nipple and letting the valve drop down, if you can't get the nipple off, people have had luck using a syringe

rpenmanparker 

Can't argue with Dave. All I can say is that I have quite different experience. All the Vittoria Corsa CXs I have used over the last several years with latex tubes have lost more than 24 psi over a 24 hour period. And Pit Stop added to them has made no difference. Zip. Go figure.

joejack951

Diffusion rate will change with the thickness of the tube and the pressure inside it. See https://en.wikipedia.org/wiki/Permeation

To say '0.5 - 1 psi/hour' is a bit simplistic in this regard given the wide range of pressures used by cyclists and variability of tube thicknesses. There is also the factor of potentially leaky presta valves/valve extenders.

himespau 

I wonder if it's a difference in the nature/brand of the sealant.

rpenmanparker 

There are basically two kinds of sealants. Those that contain natural rubber latex and those based on glycol solvent(s) with cellulose fibers. The former are recommended mainly for tubeless applications and the latter are recommended for tubes. I suspect, however, that everything we are talking about here are latex type since they are the most commonly used type in bicycle tires and do work in tubes.

Scarbo

Didn't catch this earlier!

And, it was favored by none other than (but, like latex he found it to a less than reliable material!) . . .