Entering the Realm of Tubeless Technology

"and the heavens wept with glee as the last old school tube running holdout finally folded."

- anonymous new schooler

Well, I decided the other day to give this whole tubeless phenomenon a whack. Sick and tired of snake bites in the rear, I was finally to the point that I was willing to at least try this new fangled experimental technology on my own ride. Who knows, I suppose it might work and allow me to run a little less pressure... all the while gaining some traction, comfort and speed. Plus, I couldn't help thinking that I'd feel just a little more awesome on the trails.

Now, before anyone get's too carried away... I am only going tubeless in the rear. I can't get so crazy as to run both wheels without an air bladder of some sort. These young wipper snappers of today may be all gung ho, but I have to take baby steps. Besides, with no risk of a flat I'll feel like I am cheating and may never have to work on my bike on the trail again. Now where is the fun in that, I ask you?

I knew I didn't want to use Stan's because I was afraid of the damage it might cause to my rim. I had heard it was fairly caustic and even if it was all rumor, I didn't want to run the risk on my fancy Shimano XT wheelset. My other issue was the narrow choice in UST tires, at least in tires I like. I currently enjoy the Kenda Small Block 8 for the rear, but they seem to only make a UST version in the 2.1 size. Useless for a big tire rock hound such as myself. So, I went with a standard issue Kenda SmallBlock in the 2.3 size with hopes that it would work.

Me on my way to the shop, XT rear wheel on my back:

The first sealant I decided to try was Caffe Latex... some type of super sealant from Italy. Supposedly a gentler compound that's easier on rims as well as tires. The online info is far superior to what the label on the bottle has for you to read.

Uhmmm... yeah:

Your basic info on the front of the bottle. A massive UPC code for easy checkout, some recommendations based on tire sizes, the Italian flag and about 15 European languages all saying one thing... "bicycle tyre sealant". Notice even that is spelled out in English English and not American English. Italians... don't these guys have something to do with Campagnolo as well?

Marketing department loves the UPC dominate look:

On to the back, and you might as well not even bother. Seems to be a random grouping of sample verbiage from around the world. If you are lucky enough to even find a line you can read, it won't do you much good unless you've drank the stuff or got it in your eyes. I won't even begin to debate how impossible to read the label could be once you have latex sealant in your eyes... but I digress.

Find the English:

All that said... who cares?

Instructions are for those who want to read and are afraid of experimentation. Luckily for me, I am good to go on both.

Now, they also offer a really cool injector which allows you to pump the stuff straight through your valve hole (man, that sounds gnarly). No mess and an exact measure of how much solution you have added into your tire. Bah.... who needs that type of precision and cleanliness? Plus, this injector costs more money which I didn't want to spend. So I just improvised.

Not for turkey basting:

The first thing I did was mount the tire on the wheel with zero solution. I inflated it to about 50 PSI just to see what would happen. The bead popped into place just fine and it did actually hold air. A good sign I thought. Almost right away I started to hear popping from the side wall. Tiny rubber bubbles were coming up from the casing and then disappearing with a little "snap". I figured this was the non UST sidewall not being up to the task of holding the air pressure. I hoped the latex would solve the issue. I also had leaks around the bead... which was to be expected with a "dry" mount.

I relieved the air pressure and popped one of the beads loose opposite the valve stem:

The bottle suggested 100 ml for a 2.0 tire, just under the half of the 250 ml bottle. I made my best guess and poured the stuff in. No foamy super bubble action yet. Kind of disappointing. Really just looked like soy milk at this point.

Yummy vanilla:

After clicking the bead back into place I re-inflated the wheel. This is when the action really started to happen!! I had vanilla foam showing up all over the place. Those tiny bubble holes in the casing all started to spew. I mean eject this stuff at high velocity! Like little geysers of latex everywhere. That part kinda sucked. I think with a UST tire it wouldn't have been an issue, but silly me didn't go UST. The bead started to show signs of sealing and I was on my way to getting rid of tubes forever (at least in the rear... baby steps remember).

Troubling foaming action:

I kept bouncing and spinning the wheel in hopes for the mini-holes to seal. The stuff just kept bubbling out though and it seemed my experiment might be doomed to fail. I realized gravity and centrifugal force don't cover the inside of the sidewalls very well, so I began to spin the wheel flat like a table. That seemed to be working... but slowly. I wondered how well this Caffe Latex would actually do against thorn holes if it was having so much trouble sealing already?

I decided to pop the bead and add a little more of the solution. I imagined this mass of sticky, foamy "soy milk" spilling all over the place... but it was pretty tame. You could see some bubbles in the stuff, but nothing crazy. There was evidence of coverage on the casing and rim. Still very fluid though. I added a bit more of the liquid latex and popped the bead back into place with around 50 PSI once more. Eventually the tire began to hold pressure. I span it slowly and held the tire next to my ear to listen for leaks.

Luckily for me... there were none on the first couple of rotations. Unluckily for me, one sprouted up on the third and shot latex into my ear.

That felt awesome. I'll probably end up with some sort of ear cancer now that I'll blame on cell phone usage forgetting all about my voyage into "The Tubeless Realm". That's why I write stuff down on this BLOG now... so I won't forget who to blame in the future (which turns out most often to be myself, but that's not the point).

I got the wheel back home and placed it in the garage. It was holding pressure over night, but was low in the morning. Dropped to about 15 PSI. I re-inflated to 40 PSI with no noise, geysers or spew. Unfortunately checking the pressure a few minutes later revealed a drop back down to around 15 PSI. I decided at this point my first attempt to end my innertube reliance had failed. Be it the non-UST Kenda tire or the Caffe Latex ... I wasn't sure. I had heard of good luck with non-UST tires before with other sealant products, but perhaps this ultra-thin race ready Small Block 8 was just to thin.

Fast forward a few weeks to Interbike 2009. My goal was to find a UST tire with a good tread pattern, reasonable weight and large enough air volume. I did find a few to choose from, and the Hutchinson rep was nice enough to hand over their Toro XC UST tire and a bottle of sealant for me to try when I got home. I was back in business and ready to give it another go round.

The Hutchinson solution looked very similar to the Caffe Latex. The bottle itself however held a bit more useful information:

Actual instructions on the back:

Basically used the same technique as before except this time with a UST tire. Mounted and filled it dry first with zero issues. No leaks at the sidewall or rim. Even clicked into place with a simple floor pump. Broke the bead opposite the valve stem and poured half the bottle in per instruction. Now the floor pump and bead decided to be uncooperative and no matter my ferocity on the handle, I could gain no seal. With out an air compressor at my disposal (I know, mandatory man card point deduction) I was forced to use a CO2 cartridge to get things back on track. With a "woosh" and then a " snap" the tire was in place with no leaks what so ever. Bingo!

Holding pressure overnight, I planned to take out the bike on a T100 test ride the next day. I was able to run the tire at around 35 PSI which may sound high for some, but is absurdly low for my 200 pounds of fury. I have generally been running my tires at 40 plus just to keep pinch flats at bay. The softer pressure really made for a smooth ride full of traction. I was really happy with the overall feel of the 2.1 Toro and despite the smallish casing size, found myself floating over obstacles with speed and confidence. It was a joy not to worry about getting a flat.

Dusty test victim:

All was well and good until about the final mile of trail. With a particularly rough section of downhill ahead, I decided to see what this tubeless technology could do. Admittedly, I got a little out of shape in one corner and this poor choice of line really put me hard into the rough stuff. I could feel that familiar rim to tire compression contact with a heavy thud travelling right through the frame. I instinctively waited for the tell tale "hisss" and then rapid loss of air... but of course this time there was none! How exciting, I could actually ride like shit and get away with it. Awesome!

Up the next wash and stopping, I began to hear some air escaping. Looking down, some of the Hutchinson sealant could be seen bubbling past the rim bead. I felt the tire and it was much lower than when we started. Upon closer inspection, the cause became obvious.

Rim deflection evaluation:

I had hammered the bead just by the valve stem. Try as it may, the sealant didn't seem to be bale to compensate for the now abrupt change in rim shape. To be honest, I was surprised the bead was holding at all. I quickly pumped up the air and spun the tire in hopes for a latex barrier to form. The leak slowed a bit, but wasn't stopping... so I sprinted off in front of the group I was with to try and make the car before going dead flat. The strange thing was that by the time I was at the vehicle, the air had indeed stopped leaking out and even though the tire was low... I wasn't done.

Because of my size I couldn't really blame the little 2.1 tire from collapsing under such force. The good news was the tire held and ultimately the sealant did it's job. My new found faith in tubeless technologies had me pursue the idea a bit further and I picked up a slightly different model of Hutchinson tire. It was the one I was most fond of from the show, the Cobra TL 2.25. When I removed the existing Toro tire, I found a little latex sealant creature had already been created. Was a bit troubling that such a large one had been born with just one ride. Guess time will tell how this Hutchinson sealant does long term in regards to fixing holes and staying liquid.

Hey little fellow:

The new tire mounted very easily and I added the rest of the Hutchinson sealant. Same inflation problem, but this time I realized I had no need for a dinky CO2 cartridge as I had the grand daddy of compressed air in my possession from my 4-Wheeling days (man card multiple point addition).

Hell yes:

The bead popped right in place as expected. Held air no problem overnight and was up for a test ride this morning. I set it at 38 PSI and matched the front tire pressure as well. I really like the way this Cobra felt in the dirt. Very smooth, good float and fast rolling. Traction was good, but my guess is sticky mud would foul it pretty quickly. Good thing is I live in a part of AZ where mud rarely exists even when it does happen to rain.

Fancy reptilian sidewall:

Tread pattern:

With any luck there will be a second test ride in Prescott tomorrow. Despite a few missteps at the beginning of this process, I think this whole tubeless thing is going to be sweet. I already appreciate the fact that I have to worry less about pinch flats which lets me concentrate more on riding how I want to.

The now half-tubeless equipped Salsa: