Going Tubeless for Cyclocross – Avoiding the Burp, Choosing the Best Tires, and a DIY System (Updated, Part III)
Going tubeless for cyclocross is an attractive option for anyone tired of pinch-flatting clinchers or gluing and re-gluing (or flatting) expensive tubulars. Cyclocross Magazine has long experimented with tubeless tires on our cyclocross bikes, in both cyclocross and mountain bike races, and feel that there are now so many attractive options for putting together a reliable system that it doesn’t have to be a risky experiment.
But like any new component or upgrade, it’s worth getting your tubeless cyclocross tires set up early, so you have plenty of time to fine-tune and test tires and different pressures before racing begins. There’s no better time than now. So with that in mind, we’ve given our Going Tubeless for Cyclocross Part 3 article an update, including new tires we’ve successfully tired tubeless and some new tubeless tips.
Avoiding the Burp – Tight Is Good
Perhaps you’ve read the primer on tubeless for cyclocross in Part I of our series, and learned how to convert a wheelset for tubeless in Part II, but are worried about the infamous “burp” or want to avoid the pitfalls of others. No problem. Many of us have had to learn it all the hard way, including suffering a few DNFs along the way, but you can learn from our collective experiments and mistakes in Part III of our series. (It goes without saying that like cyclocross, experimenting with your tires and wheels can be dangerous and should be done at your own risk! )
Maybe you’ve tried tubeless already, or have heard stories of disastrous burps from others. It certainly can happen if your setup isn’t ideal. Burping during riding or a race can be WORSE than many pinch flats or punctures, as an extreme burp can result in a fast loss in pressure, the tire coming off the rim, and perhaps, a loss of control. So it’s really important to get your tubeless tire system right.
Does that mean you’re constrained to Hutchinson’s versatile tubeless-compatible Bulldog and Piranha tires and a high-end, road tubeless-compatible Shimano, Roval, Bontrager, Fulcrum, A-Class, or NoTubes wheelset? Not at all. There are many factors that dictate a reliable tubeless system that can handle low pressures. Some of these are a rim’s sidewall height, depth of the rim’s center channel, rim width, a tire’s sidewall stiffness, a tire’s bead circumference and stiffness, and of course, rider weight and style. And now we’re finally seeing a lot more options in “official” tubeless-compatible cyclocross tires than the Hutchinson and NoTubes tires.
Sound overwhelming? It can be if you have to measure all of these variables and figure out the perfect combination from scratch. But thankfully for you, you don’t! We’ve done much of that experimentation already.
From our extensive testing, your primary goal is to get a tight-fitting tire when the tire is fully-mounted on the rim. Note, that isn’t the same as a tire that’s hard to mount on the rim. If you have a rim with tall sidewalls or a deep center channel (such as the Mavic Open Pro), many tires will be hard to get over the rim’s sidewall, but won’t be tight once mounted on the rim. Stan Koziatek from NoTubes says, “any tire that fits too loosely on the rim will burp air easier [than a tighter tire] when mounted tubeless.”
Road Tubeless Does Not Apply
The Road Tubeless system developed by Hutchinson and Shimano is not relevant to the world of cyclocross, in our opinion. Although road tubeless can allow lower pressures in road riding without the fear of pinch flats, the Hutchinson Tires’ Road Tubeless bead is still built for high pressure and designed to be very stiff so that it will not blow off the rim under the high psi’s required by road tires (at the high pressures of road tires, you never want to try to convert a conventional road tire because its bead will stretch).
But the whole goal is to ride lower pressures without flatting, right? Our experience has been that because the road tubeless bead is so stiff, it has a slightly looser fit in order to fit over the sidewall of a rim without stretching and without requiring tools. While the mechanical lock between the tire and a tubeless-ready rim is excellent at the high pressures it was designed for, to run at really low pressures (with sealant), you need a tighter fit, not a stiffer bead. This is why the early versions (non-carbon bead) of the Hutchinson Bulldog and Piranha tires weren’t super-reliable low-pressure performers as tubeless cyclocross tires, and as a result, tubeless tires in cyclocross quickly gained a bad reputation. Many have hear stories of someone giving it a try, and not having much luck at low pressures.
But if you already have a pair of tubeless-ready wheels and want to ride lower pressures without burping, don’t fret. You may just have to make a few mods. The Redline cyclocross team raced tubeless extensively the last few seasons, and has found a reliable, low-pressure setup by adding rim strips to the Shimano Dura Ace wheels. (Note: the newer carbon bead versions of the Hutchinson tires sit very tightly – and can be inflated with a floor pump – but require very high pressures (80+ psi and some soapy water to ensure a complete bead seat/seal.)
Get a Tighter Fit – Choose the Right Rim or Build Up the Rim’s Center Channel
How do you ensure a tight fit between your tires and rim, regardless of whether it’s tubeless-ready? There are two ways: find tight-fitting tires and build up the rim’s inner diameter. Want to get it right the first time? You may have to do both.
As Josh Patterson described in Part II of this series, to convert a standard rim or NoTubes rim, you need to seal off your rim’s nipple holes, and he recommends NoTube’s yellow tape or a layer of strapping tape. While doing this, you can add an extra layer or two of tape to build up the center channel diameter on a standard rim. Some folks use Velox tape as well, and although the cloth can do a good job of conforming to the bead of a tire, we prefer non-cotton material that does not absorb sealant.
While tape may help create a tighter fit, there’s a reason NoTube’s conversion kit includes a thick rubber rim strip. The rubber material takes up some space, effectively reducing the sidewall height, but also conforms around the tire bead, creating a tighter seal.
NoTubes’ rims, with their unique Bead Socket Technology hook bead profile, whether the 29er rim brake rims or the new Alpha 340 road rims (reviewed in Issue 12), have performed particularly well as a component to convert standard tires to tubeless.
Choosing the Right Tire
One of the benefits of running a tubeless setup over tubulars is that you are not limited come race day by the number of wheels you have pre-glued. You can select and setup a tire the night before a race based on the course conditions and weather. But to have a successful race, you can’t just choose any tire. You need to make sure the tire will seal well and not burp.
The two things you should look for are a tight fit, as we’ve already mentioned, and a supple sidewall. Stan from NoTubes says, “The stiffer the sidewall, the easier it will burp air.” Why? A supple sidewall not only offers a better ride and will absorb smaller bumps (this is why a tubular’s ride is superior) but will avoid transferring a bump’s energy to the bead. The less a bead is impacted, the less chance it has to deform and burp.
Portland’s Erik Voldengen, a long-time tubeless evangelist, blogger, and Masters A racer, weighs 195 pounds and races tubeless exclusively. He races on pressures between 25 and 30 psi, and had zero burps in a full season of racing last fall. Erik has experimented with many tires, and warns, “The stiffer a tire casing is, the higher pressure you need to ride it at.” He explains, “Riding a stiff tire at too low a pressure makes it fold over on itself and really makes cornering unpredictable. I think it also makes the tire more prone to burping. I believe stiffer tires are more prone to coming off the rim, too.”
So what’s a good tire to try? Of course, tires that officially support tubeless use are a great choice. The newer carbon bead versions of the Piranha and Bulldog tires from Hutchinson have been very good and reliable, if not heavy options for low-pressure use. We’ve been testing an early version of a sealant-compatible version of the Kenda Kommando that should be out soon and has been burp-free at low pressures, just like it’s non-sealant-compatible brother. Vittoria should have its Tubes-No Tubes versions of its cyclocross tires out as well.
But a reliable tubeless cyclocross system does not require officially tubeless-designated tires (if you don’t mind voiding your warranty), and many have had success with a number of normal clincher cyclocross tires. Results from our own experiments and those of our knowledgeable cyclocross community have shown the following:
Tires successfully used in tubeless conversions: (new additions in bold as of June 9, 2011)
-Hutchinson Bulldog (carbon bead)
-Hutchinson Piranha (carbon bead)
-Kenda Small Block Eight
-Kenda Slant Six
-Panaracer Cross Blaster
Tires that have worked well tubeless but only on NoTubes/Stans rims:
-Hutchinson Bulldog (non-carbon)
-Hutchinson Piranha (non-carbon)
-Specialized The Captain
Tires that have not worked well as tubeless:
-Continental Twister Pro
-Any skinwall tire (original Michelin Mud or Open Grifo)
-Duro Ellie Mae
Note that there are now at least seven tubeless-ready cyclocross tires on the market, with the CXM Editors’ Award-winning Specialized Captain 2Bliss, Vittoria’s XL Cross and XG TNT models, NoTubes’ Raven and Kenda’s SCT models of the Kommando, Slant Six and Happy Medium. IRC has a new model coming out, and Hutchinson had the Bulldog and Piranha carbon bead Tubeless-Ready tires, and has pledged to return to the market in 2013 or 2014.
Your results may vary depending on your rim, strips used, tire pressure, course and rider weight. Have an experience with a tire you’d like to share? Add a comment below or join the discussion here.
Sealant Options Abound
While the Stan’s sealant is the most popular option for tubeless conversions, there are now plenty of other options out there. Effetto Mariposa Caffe Latex is another good option, and provides a foaming action keeping more sealant closer to the tread throughout the tire, instead of sitting in a pool at the bottom. Hutchinson has its Fast’Air canisters for on-the-trail repairs, but we haven’t had much success with this formula. We have had much success with the Hutchinson Protect’Air Max sealant, which to us, looks, smells, and performs much like Stan’s sealant. There are also other options from Slime, Specialized and Bontrager among others.
A DIY Tubeless Rim Strip
While the NoTubes conversion kit (see your local bike shop, NoTubes.com or online here) is a convenient choice, enterprising, budget-minded riders have made their own rubber strips. Northern California’s perennial top A racer, Cameron Falconer of the Freewheel / Hunter Cycles team, devised his own system before realizing that off-the-shelf tubeless rim strips were available for 700c wheels. He uses two cheap rubber rim strips available for 26″ mountain bike wheels, just wide enough to just fill the width of the road rim. Using one strip on top of the other, he places each strip’s valve hole on opposite sides, at 90 degrees from the rim’s valve hole. Then he pokes or cuts a small hole for a UST presta valve (used on tubeless mountain bike wheels) and adds Stan’s sealant.
Other experimenters have carefully sliced an inner tube to create a DIY rubber strip with a built-in valve.
Share Your Experience
Hopefully this series of articles has helped reduce the learning curve in riding tubeless and eliminated some of the fear and myths with tubeless tires. But just as there is with tubulars, there will be a learning curve. If you’re going to try tubeless, start now, and just as you should with your first gluing job or bike assembly, test your setup cautiously. Hopefully by the time September rolls around, you’ll have it dialed. Good luck. (Also see Part I and Part II of this series on tubeless tires for cyclocross).
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I just bought a '14 Specialized Crux EVO and have a question about if the stock set-up can be converted. Information on the wheels - Axis Disc 2.0 - are not to be found anywhere on the internet... Can these wheels and the Trigger Sport tires convert to tubeless set-up. I have looked at Stan's No-Tubes website and nothing about these wheels or tires. Help! Thanks.
Using Vredestein Black Panther on Stans Alpha 340 rims. Very good. 30 - 32 lbs. Rider weight 155lbs.
Campagnolo Khamsin wheels with Maxxis mud wrestlers work wonderfully set up ghetto gorilla tape tubeless. (One wrap)
I wish I would have read these comments last fall. I'm a mechanic at a LBS in STL, MO and last fall I laced up the Alpha's for a coworker. Before we got his Bulldogs in (carbon bead) we threw his old cheap wire bead Kendas on. Had trouble with those getting seated. We finally got them to seat. When his Bulldogs came in and we tried the install, it was a very poor experience. They blew off the rim much like some of the others experience far under the recommended psi. Leaving the bead destroyed. Initially, it seemed as if the weld joining the rim together was the culprit as it was very unfinished and rough. I even had a 3rd party Alpha rim to inspect for consistency in manufacture tolerances,but that one had a smooth weld. After many emails and phone calls to NOTUBES they left me with a few bits of info. 1 Bulldogs with the carbon bead don't work with Alphas. 2 Use the CX rimstrip with MUD 2s. 3 Apparently I was doing everything wrong that they don't even have specified on there site. 4 I was told there was nothing wrong with the rim and it wasn't a warranty.........It was.
Whats funny though is the NOTUBES rep was very dodgy when answering my questions. Also, at the time I was doing this last year I found out the actual road tubeless tires have a carbon bead as well, but those seem to be fine. A little contradiction maybe? I even grilled him about that. I did find on NOTUBES website after some digging a rim description talking about how a upper bead hook on the Alpha's, Crests, Arch's, and Flow's isn't needed and they shed weight in the rim by having less of that bead hook. Disturbing! It also helps allow the tire to expand yadda yadda yadda stans jargon. After reading that and hindsight of my experience with the Alpha rims last fall. I'd be nervous to recommend them. For fear the bead will blow off. The logic is "whatever", but the proof is in the practice.
I'm not completely writing NOTUBES off my list. Late last summer I E.P.'ed a stock Stans Crest 29er wheel set. I put them on my monster cross bike with dropbars/disc brakes and raced all season. Just for reference I raced both SS and the B race back to back for about 8 or 9 races so about 18ish races total. I used the Bontrager CX0 700x38 tire(yeah i know, not legal) front and back tubeless with stans sealant. I needed to add extra sealant before they would not creep down in psi. In a variety of conditions they only failed me once and it was a puncture. when I checked to see if there was sealant I found that it had dried up due to me not using enough in the first place with a non-tubeless ready tire. I got the psi down to around 20-23 in a couple races, but was sketched out and had to ride real light. I road regularly at 25-28 psi. I weigh in at about 150lbs. I never did burp them, and there were a few times I probably should have.
So for what its worth, that was my longwinded experience.
We have some demo Ultegra 6700 wheels at the shop that i'm gonna try some different cx tires on hopefully soon. I keep asking that coworker mentioned above to bring one of his Alpha 340 wheels to work so I can experiment more with tire options again. Much like others I like to tinker and get things to work.
So what are best clinchers to mount tubeless to Utegra 6700 wheels? And u think I would need a tubeless rim strip on these already-tubeless rims so the tire will fit tighter? If so, which kind would u recc?
using Ultegra 6700 wheels, need a tire for the gravel-dirt race Crusher in the Tusher. The Raven is proven, but I am also taking a look at the Kenda Happy Medium. I think the Kenda site says they are now compatible with liquid sealant. Anyone mount the Happy Medium tubeless and have some feedback?
So..... I just mounted up two Clement LAS's one to a crest and one to a 355... Both seem to be bubbling a little. I do not get this with the PDX or any other tubeless setup that works. I even inflated both twice and used just the foamy suds to help seat the bead.... Not to stoked. I am stoked on the tires themselves! Just went around the block on them and they roll smooth as idkw!
I decided to try tubeless for this cross season. Why? I figured why not? I like tinkering with stuff and this seemed like something fun to try. I weigh about 210 lbs and after much consideration, I decided to use the Shimano 6700-WH wheelset. I wanted to run the wheelset using road tubeless on my road bike after cross season, and the 6700 seemed a better choice than running the Alpha 340's laced 32-3 cross to another hub. Cost was about the same for both. At my weight, I was also concerned about some reports of the Alpha rims being a little weak. The 6700's have no weight limit, which probably has no meaning, but made me feel a bit better when I made the purchase. Still, I was hesitant about the low spoke count (16 front, 20 rear), but I figured that if they were getting beat up in cross, I would just reserve them for road use.
I ran Hutchinson Bulldogs and had ZERO issues with the setup (much to my surprise). I was able to mount the Bulldogs by hand and seat the beads with a floor pump. The wheels stayed true and I never had a single burping problem and zero flats. I generally ran 35-40 psi, and I never tried really pushing the low pressure limit. Somebody who is lighter and faster may put different stress on the tire, but I ride pretty hard (I'd like to think) and never had issues. I actually put about 80 goatheads into them once when I decided to take a "shortcut" along a railroad track. They lost quite a bit of pressure, but I was able to make it home (only about a mile). After adding a little more sealant and then spending an hour pulling out all of the thorns with needle nose pliers, they sealed back up (again, much to my surprise). Actually, the biggest problem that I had was trying to unseat the beads. I would deflate the tire and then push and push and push with my thumbs to try and unseat them, to the point of getting blisters. I wrote Lennard Zinn for advice, he actually wrote back... "try pushing with your thumbs". Finally I tried putting hot water on a section of the rim and that actually helped to break the bead. Once cross season ended, I put a set of Hutchinson Intensives onto the 6700's, a much harder mounting process relative to the Bulldogs. I had to use tire levers to get the tires onto the rims and use a CO2 cartridge to get the beads to seat.
In the meantime, I decided to convert a set of Open Pros to tubeless as an off season training set, again with the Hutchinson Bulldogs. The Open Pros are pretty notorious for being difficult to run tubeless, but it is what I had, so I thought I'd give it a shot. I used the Stans rim strip and after using 2 layer of the Stans tape, I had all kinds of problems with burping, even at 40 psi. I could actually get them to burp just by pushing down firmly from the top. So, I put two more layers of strapping tape on top of the Stans tape, and since then, I've had no problems with burping, even running down to 30 psi. I would not have guessed that two layers of tape would make such a dramatic difference.
If you are thinking of trying tubeless, my advice:
1. Do lots of reading. The article here has tons of good advice. Watch the videos on Stans site and check the Stans forums as well.
2. Be willing to do some adjustments to dial in the setup. Don't get discouraged.
I used the ZTR Alpha 340's for the 2011 season, mainly as race wheels, for both road and 'cross. I weigh 174 lbs I used a DT Swiss 240 front hub, and a Powertap Pro+ on the rear. On the road, I used Specialized S-Works turbo tires. I primarily racing criteriums. I ran the tires at 90 psi, and did notice superior traction when cornering, and felt very confident on technical courses. The only negative point was the rear wheel constantly needed to be trued. In general my experience was favorable, and I did not have a single flat on these wheels for the entire summer. I did not get much success sprinting with these wheels, but that is probably my shortcoming, not the wheels'. They did serve me well in hilly races.
For Cyclocross I used Specialized The Captain tires. I had 4 flats in races as a result of burping (an issue with the rims, not the tires), and had to run the tires at around 40 psi to prevent burping, losing the advantage of being able to race at low psi. The rear wheel also rubbed against my frame, removing the paint on both chain-stays. An indication of lack of lateral stiffness? After 20 races the rear rim is trashed, and will have to be replaced. Rear wheel trueing remained an issue.
These rims are a good road option, particularly for hilly races, but not a as suited for hard racing on technical 'cross courses.
I am a long-time user and believer in the Stans 355 rims running tubeless. I recently purchased a set of the Alpha 340 wheels and have been having trouble with getting the tires to seal. Mind you, the tires I'm putting on the Alpha 340s are exactly the same tires I had on the Stans 355's, running tubeless with no problems. Hence, I have been doing my internet searches and came across this article and it's posts. It had not occurred to me until now that the problem could be the Alpha 340 rims themselves. So it sounds like I may have some lunkers on my hands. Are there ANY tires that people are satisfied with on the Stans Alpha 340s? The reports of the Hutchinson tires seem mixed; either you can't get them on the rim, or you can but you ruin them in the process? I assume the Stans Raven CX tire works, but I feel a little short-changed if that's the only tire I can use with these new wheels. Thanks for your help!
I am riding Clement crusade pdx's on alexrims da22's. I am new to cx and am riding a brand new Ridley x- bow. Should I go tubeless with my setup?
I have the Alpha 340's 32hole. I have run the Pirhana and Bulldog's I have had 3 tires fail so far. Do not ask why I keep going back to them. The carbon bead seems to be the flaw.. Otherwise a great supple ride 200lbs with 30-35 psi. 25 if muddy as hell. Done 3 races. One race got me 4th place at a cat 4 race with 80 riders! The rear pirhana did seam to blurp on me for the first time going around a turn but I am not positive. Thanks again @notubes
am I missing something? with two layers of tape, neither the mud2 or vittoria xm fit tight on my stan's rim rim. my xm burped after a remount last sunday resulting in a dnf. I weigh 170 and was riding at 45psi. the mud2 doesn't seem like it will work any better. Also, what it the advantage to gluing tubless tires to your rims vs. just riding tubulars? tire cost?
I would love to see an additional measurement added to this list, which identifies which of the "tubeless compatible with Stans rims" tires are compatible with the UCI 33mm or less rule!
@MatthewHargrove Peter...thanks for the reply. I am happy to report I did a Stan's conversion and all is well. The rims are DT Swiss made, so they have a deep well, and it took two layers of Stan's tape (I then ran out) and then two layers or electrical tape (all I had) in order to get them to seal up. But, they have worked great since then. I have done three cross races and a cross country race (yes, a Mtn. bike course on my cross bike), and they worked fine. The non-2Bliss Triggers are fine for now while it is Summer and very dry, but I will swap them out for the 2Bliss Tracer's as soon as they are available. For the CX races I ran the psi at 30/31 and they held fine. No burbing, no loss of air. They are 38c tires so there is plenty of volume - to the point that they can feel a bit too squishy, but I think part of that is just getting used to the feel of tubeless. For the XC race I ran them at a higher psi, 35/36 because of the rocks I had to deal with and fear of bending the rim on a hard hit, and they performed great. Again, no burping or loss of air. I know I don't have the ideal set-up... and using so much tape (and the wrong kind) is killing me on the weight advantages, but when I get new tires I'll use proper rim tape! I am happy with the set up for flat protection (was tired of dealing with thorns) and I know I avoided several pinch flats in the XC race as I hit some rocks and the edge of a bridge and a log hard enough to bottom out the rim. Happy so far.
Hey man, check and see if there isn't the Spesh tubeless rim tape already on there. I know they are doing a lot of that now. And I would personally wait for the new Specialized 2bliss Tracer pro. A lot better tire that is specially made for tubeless and a better all around tire than the Trigger. Anything more than hard-packed dirt or gravel you will be slipping and sliding all over the place with the Triggers. And if there is no 2bliss tape on the wheel, I've had good luck with the Stan's No Tubes Rim Tape. I recommend wrapping the rims at least two times, considering Spesh wraps their wheels three times. Hopes this helps you out man!
@JeffCospolich Without a rim strip, you really only have two options - the carbon bead hutchinson piranha or bulldog. both aren't made any more but are still available in many shops. these are the only "road tubeless" cx tires made. RT is what Shimano supports.
To convert other tires for tubeless, you'd need a rim strip. I'd pick one for your rim width, but we've have great luck with the NoTubes rim strips. Good luck.
@JeffCospolich We've had good luck with almost all Kenda tires tubeless including the Happy Medium, but mostly on Stan's NoTubes 29er rims. With the Ultegra wheels, you'll still need a tubeless rim strip for good results. The Kenda Happy Medium won our editor's award for best file tread clincher (see Issue 16), and has some great width options and is a longer-lasting tread than many other filetreads.
@bog5000 Great stuff, and similar to our experiences. on your converted wheels, don't be afraid to try some standard tires listed above...we have had better luck with those on conversions.
Hi @hero_snow , stay tuned for part 4 of this series, coming soon. But Stan has an alpha 340 rim strip to help in tricky cases. From our research, it comes down to width, and the narrow rim doesn't offer the same bead support as the 355/ZTR 29er. We have had plenty of luck with a handful of tires on that rim, including the Hutchinson carbon bead Bulldog and Specialized Captain tires, and a Kenda Slant Six. It's certainly not as forgiving as the 355 but it can work. Good luck.
@cambellian We love tubeless, and have gotten it to work well with the Clement Crusade PDX. We don't have much experience with the Alex DA22, although Stan's NoTubes conversion kits often work well. Tubeless can provide great low pressure benefits without the lead-up time required by tubulars and with an easier ability to fix flats and swap treads. It's not for everyone, but many of us are converted. Good luck, and let us know what you end up doing.
@MikeClark1 Which rim? The Alpha 340 or Stans 29er? Sorry to hear, you should definitely be able to ride lower than 45psi. Someone at your weight should be able to ride 45psi with road tubes and not pinch, we'd think. That's definitely not worth it.
@stormH2Odesign it depends on the stans rim - 29er or 340 since they vary quite a bit in width. yours was measured on the 29er 355? or ztr race? thanks for the list!
@cyclocross @JeffCospolich I just got a pair of 6700 wheels, and got a Michelin Jet to mount to the front without too much trouble, and a scoop of Stans. No rim strip used. (I didn't know I'd need one). The rear wouldn't inflate though. Do I need an actual rubber stans strip, or would a few layers of strapping tape work around the center channel to build it up to help it seat?
@cyclocross Well heck, you guys have been great. I'm not a big writer-inner, but this has been helpful. I'll stay tuned.
@stormH2Odesign Hi, and thanks for the rapid reply. I do have access to a 10hp air compressor, and I do always remove my valve cores. In this case I did not soap the bead, but I don't believe that is the problem. To be more specific, the tire (Maxxis Raze, which I see is listed above as a known tire to NOT work... except again it worked fine with the 355's) goes on very easily and I am able to get the tire to take air pressure, even with a floor pump. The problem is, the bead becomes unseated at normal running pressures (35-55psi). Once, I had a fully sealed tire at about 50psi that had been sitting still for approximately 15 minutes undisturbed (wheel laying next to a friend of mine) and the tire just unexpectedly blew off (and blew Stans juice all over a new car and my friend, which was actually kind of comical). Another time, I was 2 minutes into a CX race and the rear tire just blew off completely. This was disconcerting, because I had been riding the same set up through car traffic and such. Anyway, it would seem like either the 340s are a slightly smaller diameter than the 355's, or the bead socket is not as "grippy", or lacks the ability to lock the bead in as well as the 355 rims did.
Anyway, so yes, I need new tires. But now I don't know what to get, because the Hutchinsons sound like a poor fit.
From the list above:
-Hutchinson Bulldog (non-carbon) ..........they don't make these anymore (in non-carbon)
-Hutchinson Piranha (non-carbon) ..........they don't make these anymore either
-IRD CrossFire ..........these are a viable option, except only 32mm
-Schwalbe Racing Ralph ...........these seem the best option
-Ritchey Excavader ..............these seem stiff, cheap, low TPI
-Panaracer Cinder-X .........same as IRD, hard to get?
-Specialized The Captain ...........this is not a cyclocross tire, it's a mtb tire, don't know why it's listed
it's the alpha, and my third race tubeless. I was riding at 45 to avoid burping. This is my first season of cross. I've had two dnf's because of flatting. I am so frusterated right now. my next race will be with the alpha/xm and a tube filled with stan's sealant. I figure that even if I pinch, the tire should have a strong enough seal to keep air in. If glue is the only answer, expect to see my clincher wheelset on craigslist soon :(
@cyclocross I measured mine on the 340 rim, but I don't see how the rim width would change the amount of tire material (lay the tire flat and measure bead to bead) there is to form into a cross-sectional volume. Since the 29er rim is slightly wider, the tire would not become narrower after inflating. All it will do is widen the cross section of the tire volume where the bead hits the rim, effectively allowing more air volume at a given pressure.
The UCI officials are interpreting the rule in a positive way, to me. As long as they can shove the measurement tool on the tire, it seems to be allowed. The relative ease of this depends on if the tire is dry or wet (friction) and the pressure it is inflated to. With a Tufo Cubis 32 tubular, the tool will slip on very cleanly w/o friction. It is a true 32mm. The tool will still fit over a 34-35 mm Stans Raven tire, even though it's clearly too big. I get the impression that the officials realize the rule is stupid, it's too vague to enforce, and feels awkward to tell an elite rider his tire is "too fat" while the top pros on the front line are riding the same brand and model of tire (Clement PDX).
The stans rims have a psi rating and you were clearly exceeding it at 85psi (I think they are like 50-55psi). You don't need to air the tires up more than 40-50 when getting them seated. Yes, the soap helps it pop into place. I don't get as much of a "pop" sound with the Hutchinsons when I tried them a few years ago (non-ust, first generation). At the lower end of that pressure range, you can pry the tire back/forth after inflating and spin it at the hub to see if it is seated consistently, or if not, it will slip into place. You can also look at the relative location of the mold line at the outer bead/sidewall area and how it parallels the rim. That will indicate it is seated. You don't over-inflate the tire to "hope" it will go into place. Normal riding pressure for CX racing is 30-40 and as you ride, the tire will shift and flex a little, also helping it to settle into position. There is no need to use glue at the bead (as others have suggested) or rim strips as the Alpha 340 is already pretty shallow, but if you absolutely need to (if you are using a loose tire), then give it a shot. I've found that Michelins and Hutchinsons are the tightest.
@cyclocross Saga update; went to the LBS last night, bought a Hutchinson Bulldog for the Alpha 340 rear wheel. (Thought I'd try one first). The tire went on perfectly; a good snug fit, difficult but certainly possible to put on. Never used a tire iron except for the very last maybe 5 inches that I couldn't fold over by hand on one side. Pumped the tire up without any sealant, and it held air. That's always a great sign. I couldn't get the bead to pop though, and I could see (by looking at the sidewall) that about 1/4 of the tire was still not seated. The max tire pressure on the sidewall of the tire is labeled as 85PSI, so I pumped it up to 80PSI to get the bead to pop. BOOM! Bead broke, tire exploded, and I sent a few trick-or-treaters in a flying panic.
The tire is shot, the bead is clearly deformed and not repairable. I'm going to take the tire back to the LBS and see if it's a warranty issue. Clearly next time, this tire will need soap. Ever tried Vaseline on the bead?
@EricMorgan No rim strip, single layer of yellow tape. Stock wheel set, the heaviest one that is a little over 1400 g.
I'm wondering if you are using the a rim strip on the alpha 340 and also how many layers of stans tape you are using.
@hero_snow No problem. The Jets worked just as well for me as the Mud2's, and even better were the Stan's Raven's. Of those three semi-slick treads, I felt the LAS was the best due to the edge knobs.
@stormH2Odesign Perfect. Thank you much. I was actually eyeing the Vittoria Cross XN Pro with envy this weekend because of it's open tread pattern, but it looks almost identical to the Clement LAS. I've heard conflicting information about getting the Michelin Mud 2's to run tubeless, and I had trouble getting the Michelin Jet to go tubeless on the Stans 355's, so I gave up on Michelin. I will consider using them again though, because I always liked that tire.
Thanks again for your help.
@hero_snow You can't go wrong with a Michelin Mud2. They are a slightly tighter fit than what I'm using in the UCI elite races, which is the Clement PDX and LAS tires. They are both proving to be reliable for me on the 340 rims at 30-34 psi. I'm 172lbs. I was bombing past riders last weekend in Boulder who were using tubulars in the most nasty mud sections. Excellent edge knobs and open tread.
The 15 psi pry test suggests that the Michelins are very slightly better at resisting burping, but both tires are pretty reliable at normal racing pressures, in my experience.
@cyclocross I spoke with Don K. last weekend at the Boulder UCI races. He said that they are still struggling with getting the mold process dialed to where they can ensure a properly sized tire casing that falls within the 33 mm rule. The first run was designed to be 32.5 and it came out as 28, then they did another round of mold making with a goal of 33.5 and it turned out as 34-34.5 mm !? I guess it is quite difficult to work with such tight tolerances the UCI has mandated in manufacturing. Even the high-end tubulars of other brands struggle with this between batches.
I use the Stans ZTR 355 rim, if I glue my clincher on, does the glue prevent the tire from locking into the bead hook? When I air the tires up now i hear a loud pop as the bead seats into the bead hook. That sound gives me confidence to run low pressure. Currently I'm running non carbon bulldogs(on my last pair looking for a replacement) and I can run them as low as 25psi (verified by digital gauge) without issue, I do bottom out the rim, but no burping. I weigh 160lbs.
@stormH2Odesign This confirms our experience as well. Originally they were so easy to install, we didn't think it'd work. Then we tried to inflate them on a set of wheels and when we couldn't easily, we gave up. It wasn't until Donn at Clement told us that he saw a set mounted on Ksyriums with no problem we tried again on the Stans NoTubes 355 rim. We've had good success on that rim, but that might be the most forgiving tubeless rim made. It did take some setting up and some flat-on-a-bucket sealing.
@robkerr After contacting stan's, I've learned that an alpha specific rim strip is needed to prevent burping.
@robkerr thanks for bearing with my pessimism. It's hard, dropping a few days pay on a setup billed as the end of my flatting days, buffering it with a tubeless specific rim, picking a tire off the "worked well for us" list, adding an extra layer of tape, running more psi than I would have liked, Doing well in a race, then my tire belches air. The growing confidence I had in this system went just as flat.
No doubt, till the burp, tubeless is faster, more comfortable, and probably more reliable than tubes, but is the ride/reliablity any better than tubular? If not, why go through all the trouble? As far as I can tell (from what I've read) the only downside to tubulars is the glue.
@MikeClark1 You're missing the details mike. The cement is far from permanent, its just sticky. Recall the tubeless benefits; the lower pressure increases traction and ride comfort (both primary goals to me). There is no inner tube for snake bite punctures. The rotating weight is less. Tubeless is a stage between clincher and tubular that is more flexible and with sealant, awfully reliable. Again, I can't begin to think about the number of flats or burps I might have had in the intensity of racing, yet never knew because the system worked for me. Shake your frustrations and spend some time away, or really into it.
tubeless for cross seems sketchy and unreliable to me now. I'm sure gluing the tires on works beautifully, but isn't going to that extent for a reliable setup negating all the benefits of clinchers? If we are breaking out the tire cement, and somewhat permanently attaching tires to rims why not get the ride quality and weight advantage of tubular tires in return?
@MikeClark1 Mike, I'd agree with Rob that maybe the tires aren't a great fit. We've had good luck with Vittorias tubeless but maybe something changed. I do know that the Alpha 340 rim isn't quite as burp-free as their 29er rims. If you can get a Hutchinson Bulldog with a carbon bead on (it's tight) you'll prob have better luck. I can tell you that except perhaps for thorns, sealant in a tube will not help for pinch flats. We've tested that extensively.
Good luck. It can be done...we promise. Another alternative (see our pinch flat testing in issue 7) is trying other tubes. Big heavy tubes or latex can help.
Adding to the PDX Clement tire subject... I typically use an air compressor, removable valve stem core, stans sealant, and soapy bead when I pop up my tubeless clincher tires into place. This makes it a no-brainer.
The new Clements did not inflate for me right away. I initially cast them aside thinking they were too loose and not a good tubeless option. I instead mounted them onto another rim w/ a tube inflated. After a day of stretching (the tires were packaged previously in a folded state), I tried it again w/ the air compressor... voilla! No issues inflating whatsoever.
The Clements are looser at the bead than a Michelin Mud2, but tighter than several other tires I've tried. Tighter fit is better for sure. With the pry test, I could get some burp-spits of sealant w/ the Clements, but nothing w/ the Mud2's. Folding and prying the tire flat against the rim back and forth all the way around the circumfrence of the tire, there were numerous little spits. It all added up to only 1-2 psi of pressure loss.
After a few rounds of the standard "shake-and-lay-flat", I'm not able to get any further spitting during the pry test. I do that at 15-20 psi, which emulates the lateral forces I'd be putting on a tire if I folded it all the way to the rim w/ too low of pressure. Doing this procedure can help you to gain confidence in the reliability and structural soundness of the tubeless setup - good for the mind. A few follow up test rides will confirm it and you can proceed, worry-free!
28-35psi is a pretty reliable pressure to work with using a tubeless clincher.
Chin up Mike. It sounds like a basic problem in that the tires you have don't fit snug. First, fix that problem (either find a set, trade, start over) or add the tape and work slowly to get the tire to fit in the bead and hold some air before the sealant, and before any thoughts about glue.
On the glue; it is tacky like pitch from wood, not like super glue ruining tires and rims. With air, it helps resist the tire deforming on off-angle impacts (burp). The glue is another step of insurance after the first two steps go smoothly. It works. True, it isn't fun to rub-off later, but it does come off and does not ruin anything. If all goes well, the tires will wear out and another set goes on.
I have been sloppy and hit rocks from all angles running 40psi. and it has all held together. I, too, weigh 170 lbs. We are racing in the super-wet grass/mud/gravel with curbs and potholes for the next several weeks, and I have confidence in my Schwalbe EVO Racing Ralphs on Fulcrum rims from 32-40psi. My teammate got through several days of frustration getting his set of Clement PDX Cross clinchers to hold air, then had a fantastic race last weekend on a course where many flatted. His appear to be "set" really nicely now.
If selling the clinchers is the end of the frustration, consider too the value of pit wheels.