ultralight tubes in my saddlebag, because they pack much smaller.

Really??? Still spreading this line.... Your math skills are scarier than this fantasy you keep having.
Since you insist that advertisement counts as science.
Let me refresh your memory:

"..in the lab should experience latex resulting in a reduction of rolling resistance from 1.4-5.6w. Rolling resistance should be higher on the road, and thus the savings greater. The cost of rolling resistance on the road could be 50w or more for a 200-pound person. Latex tubes can reduce that cost by 10-20%. "

10% of 50W is 5W, 20% of 50W is 10W === how did you get 20W out of that math, you should at very best use low end as real.

Next:

"We pumped up the tires and rode. We didn't notice the tubes making a performance difference, ... saving even 5w would be hard to measure on the road."

I just tried the Challenger latex tubes. They are in the low 60s gram range. I also put 105 psi in the front tire and 110 in the back. I didn't have any trouble for 350 to 400 miles. Then, as an experiment, I decided to go back to the 120 psi I had been using in both tires. The wheels did seem faster, but in less than a mile I heard a big bang; the tube was blown outside the tire (only the valve stem was inside the tire). So, I am not sure what I will try next. Maybe a lite butyl tube. Maybe stick with the latex but just stay around 100 to 110 psi. The latex tubes do leak faster than butyl tubes, but that did not bother me. I ride almost every day and I could get two rides out of an air job. Was this just a freak accident. If you use latex tubes, do you inflate to 120 psi without having any regular problems?

It's not the tube's job to keep the tire on the rim, so the most likely answer is that you had the tube trapped between the tire bead and the rim, and it eventually heaved the bead overboard. Alternately, you may have a marginal fit between your individual tire and rim. In any case, we'd all be in serious danger if it were our inner tubes' job to keep the tires from blowing off the rim, so if you liked the tubes, maybe try again. After installing, peek between the rim and tire bead all the way around to ensure that the tube's not under the bead at all.

I only ever use latex tubes. They are lighter, take less space and seem to roll smoother than butyl tubes. Some people think they are difficult to install and lose air quickly. The first one depends highly on the skills of the person installing them. The second, I inflate my tires before every ride anyway so thats not a problem for me. I'm never going back to Butyl again...

It's just a myth that they puncture easier! Whatever goes through your tire will puncture your tube, doesn't matter if its butyl or latex, lightweight or thick.

How do you patch latex tubes?

I use latex condoms and have never punctured, so I'd imagine that the latex bike tubes would be similar.

I wouldn't patch latex. Not worth it considering the immense cost of medication for AIDS, hepatitis, etc.

Head on over to the addiction thread. They will love you there.

In the meantime, I would be interested in knowing how to patch latex tubes since I will be trying a set this upcoming season.

I've never used latex tubes...in fact, until about a week ago I didn't even know there was such a thing. But the mechanic who told me about them last week insisted that, while latex tubes are more prone to punctures, they're less prone to pinch-flats, and so ultimately wind up being less prone to flatting overall. I then did some internet forum searching and found quite a few folks who agree with that characterization of latex tubes.

Also, this "they leak air faster" thing seems to be a red herring if you inflate your tires before every ride. I have yet to read an anecdote claiming they leak air too fast to be viable for an entire (single) day out on the bike.

10 watts is significant. For an average sized rider with an FTP of 320 watts, a 10 watt savings is worth 39 seconds in a 40 k time trial. That is easily the difference between winning, and out of the money.

Also, it takes a lot of training to increase your FTP 10 watts.

That said, Latex tubes, in a very low rolling resistance clincher is likely the lowest rolling resistance option available.

You're right. Over the course of 24 hours, a typical latex tube will lose enough air, it needs refilled. Depending on the particular tube, and how finicky you are about air pressure, you can often get by for a couple of days.

But even on a very long ride, it would not be an issue during the course of a day.

I would hope you're not rolling through glass, nails, wire, sharp gravel, etc.

I have mistakenly used the ultralights and never found much of a difference. I grab what is on sale. Do they flat easier? When taking out the possibility of pinch flats, terrain and condition of the tires it is probably negligible

I created a good solution for the regular butyl tubes...use a FoodSaver vacuum bag. I deflate the tube a much as possible, then make a foodsaver bag just big enough t get the tube into it. Vacuum it, seal it up and cut the excess bag around the tube off. Two great benefits...1) it's compressed to the smallest size and 2) since it's in the bag, it slides into storage spaces better. Otherwise, rubber usually will grab onto everything as you try to cram it into the seat bag.

It might also extend shelf life of the tube, as there is very little air to rot the tube. But in reality, I'm using them up rapidly enough that they aren't sitting for years...

Jobst Brandt's answer:

To patch a latex tube, make patches from an old latex tube that are fully rounded and just large enough to cover the hole plus five mm. For instance, a thorn hole takes a 10 mm diameter patch. Use Pastali rim glue (tire patch glue also works but not as well) wiped thinly onto the patch with your finger. Place the patch on the tube immediately and press flat. Latex will pass the volatile solvent allowing the glue to cure rapidly with good adhesion to the tube.

Michelin say you can patch their latex tubes with a regular patch kit.

I haven't tried either. We just run latex tubes on our TT wheels, and also the latex tubes in my tubulars, but I don't patch either of those.

I ran a forte lunarlight 50gm tube on the front and a 120gm tube in the rear that a repair shop put on for me after a flat during a century. Had both for ~1000 miles, no flats in either one but I did notice that the light/thin tube would leak air a lot faster than the fat/heavy one.

I recently replaced both tubes with 70gm Forte ultralight vs lunarlight tubes and noticed that they both hold air almost as well as the super heavy 120gm tubes. I'd personally avoid paper thin 50gm tubes and stick with 70gm tubes - less risk of a pinch flat.

I've never used latex tubes (except when they are part of my Vittoria tubulars) so I can't comment too much on their functionality. I did switch for a while from using Conti Race 28 tubes to the Race 28 Light version and did notice an increase in punctures and blowouts and couldn't really feel any performance difference (ecept for my wallet being a bit lighter as they were nearly twice the price). I've switched back to the regular Race 28s now.