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Tech geek and racerboy
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Discussion Starter · #1 ·
So after running tubulars for a few weeks now I have learned a few things about them:

First, the bad: Tufos tape alone is NOT sufficient, even when installed properly with a tire made specifically to be used with it. I rolled a tire on a high speed, off-cambre corner near the end of a race. Luckily the tire was undamaged and the rim sustained only a tiny scrape before I slid safely into the grass, and I managed to remain upright. Tape remained intact on the rim but cleanly detatched from the tire, which was wet underneath. My hypothesis is that water from torrential rain and creek crossings may have been wicked under the tire by way of the cotton base tape and/or casing and reduced the bonding strength of the tape to the tire. Combined with the increased leverage of a large-volume tire at low pressure, the bond was obviously inadequate. Tufos tape may still be adequate in completely dry conditions, but after my experience I am now unwilling to risk it.

The problem was clearly between the tape and the tire, not between the tape and the rim. I have since learned that the tape is used often by cyclocross racers as a first layer on the rim before using glue as normal to facilitate easier cleaning/removal when changing tires, which I will likely try in the future. For the time being, having had the tires properly glued I can now corner hard at low pressures with no fear of rolling a tire.

Which brings me to the good: performance of the tire- almost independent of size and tread- is outstanding on nearly any surface (barring clingning mud, which I've been fortunate to avoid so far). I attribute the performance more to the tubular technology than to the tire tread. I went from relatively knobby GEAX Saguaros with generous volume to much smaller and less knobby Tufos XC2 tires, yet still experience huge benifits in cornering and overall comfort when compared to clinchers. The larger heavier tires were better overall, but the smaller, lighter tires are still damned great. I would not trust the same tire as a clincher and strongly doubt that it would perform nearly as well, especially when pushing hard into a corner on rough terrain. Even with the small tires, I can lean the bike into off-cambre corners with confidence I would never have on a clincher XC race tire.

Other than the tape failure, reliability has been fantastic and the wheels themselves are amazing. Running sealant in the tires, I have not had any issues with flats. The overall weight reduction of the system is substantial compared to even the lightest clincher rims. For XC racing, I think tubuler MTB are certainly becoming a viable option.

Finally, I got some reliable intel that interest is increasing in the industry and that several major companies are working on MTB tubular tires and rims for next season, which is great news. I can't wait until there are a few more higher-volume tires available from some of the brands we all know and love.
 

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I'm not surprised to hear about your roll-off with only the tape. On a cx bike, glue is almost always used because of the low pressure used for increased performance. On a road bike, the pressure is so high that I think they can get away with just using the tape.

For mtb or cx though, glue is a must. I've glued tubulars on my cx bike wheels before and although it wasn't fun, it isn't hard to do. Just do a search on RBR for how to glue cyclocross tubulars on and go from there.
 

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If you run sealant in a tubular tire, what do you do
if it hardens? I can't think of a way to get it out. This
doesn't seem like a good idea to me.

Best, John
 

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cyclocrosser do NOT use the Tufo tape as a first layer.
Some...including me, use Velox tape and glue. It makes for a very strong bond and impervious to water. But it is very hard to get the tire off.
The Tufo tape works on road tires where the pressure is high and the leverage low. I got it to fail quickly at low cross pressure.
Learn to glue with either conti or mastik...and check them after wet races...it's the only way mtb Tubbies will work.
 

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Discussion Starter · #8 ·
'Crossers and roadies have been running sealant to prevent and repair flats in tubulars for years, and it's the use of sealant in particular that makes tubulars a viable option for mtb racing. See Leonard Zinn's explanation on Velonews for draining sealant from tubular tires. I also use Caffe Latex in the tubulars and have experienced no issues with drying up so far. I anticipate these tires will wear and be retired from race use before the sealant is dried up.

bad mechanic, tubulars are superior in performance to a tubeless clincher simply because the whole tire casing can flex and conform to the terrain in a way that is impossible with the clincher interface. For an illustration of this concept, check out GEAX's website and look at their "MTB Tubular" benifits page. There's a neat little graphic that I think shows it quite well. Remember the first time you rode a normal clincher converted to tubeless with sealant? Going from tubeless to tubular is at least as dramatic in terms of increased traction and cornering, but without the possibility of rolling the tire or burping at lower pressures (tape issues aside).

In addition (and the primary reason this thread is being posted in the weight weenies forum), the rims can be built both stronger and significantly lighter than any clincher rim simply due to the complete lack of a bead seat on the rim.

Mayor, I spoke with several cyclocross racers, in addition to several tire reps, and all of them suggested using the Tufo tape as a first layer. It's my understanding that the concern is not the strength of the tape itself but rather that of the adhesive interface with the tire, which in this application would be completely replaced and covered by layers of glue. I can see how using a pourous material, such as Velox rim tape, soaked in glue would make for an incredibly strong bonding surface, though. Thanks for the tip.
 

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Hardtail,
You are getting it wrong with the tape.
It is NOT Velox rim tape, but Velox ( and a few other mfgrs) tubular tape... a double sided adhesive tape. Go to cyclocrossworld and read the tech section.If you use this method, the tire in ON there.

I don't know where those guys are getting their info....but my guess is they are just pulling it out of their butt. The Tufo tape works on road tires....but I have been able to roll cross tubies with it alone and with the Tufo tape and glue, which means a bigger mtb tire would be easier to roll.

If I were going to run mtb tubies...I would use this method.
2nd choice would be glue only....and check the tub's every ride( especially after water)
 

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Listen to the mayor on this one. Tufo tape is complete garbage for MTB or CX applications. My wife does UCI CX races and I'm a 2-3 race hack. We have 8 sets of tubular wheels for CX racing and a couple more for road. Tufo tape doesn't get near any of them.

The Jantex/Velox double sided tubular tape does work quite nice. But, as mentioned... it is a PITA to get off. However, if that method is done correctly, you should rip the base tape off the tire before the glue bond between the base tape and rim breaks.

I just use regular old Vittoria Mastik on everything now, as I don't like having to pick the damn velox tape off the rim when replacing a tire. I also glue all of the tires for many people on our team and we've never (knock on wood) had a rolled tubular.

I know three people personally who have used Tufo tape for CX... all three rolled their tires at some point in the season. A couple were on hot days... when the tufo tape doesn't hold well. The others were after about half a season of use. Inspection of the rim and tire clearly showed that water/mud had contaminated the tape joint. That is the major weakness of the Tufo tape.... it's just too easy for junk to get into the glue joint.
 

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Briscoelab,
You are going to lose street/forum cred agreeing with me.....;)

I hear you on getting the tires off....it is a trade off for tires that really stay on.

And with the glue/tape method, I can do up a set of wheels in an afternoon...as opposed to several days of layering glue.

But I do have a set of wheels that I use glue only on...semi slicks that never get wet( and still get checked regularlly) and I use the wheels for the road during the summer.

One thing you have to keep an eye on, no matter what method you use, is dirt contamination. Once it gets in there, the grit cuts away at the glue. The glue/tape method helps with this...but you still have to check your tires.

As much as I want to try mtb tubies....not being able to repair them easily in the woods and the broader chance of rolling one in a long race are turn offs right now. But, if I did races that were shorter or had a pit....I'd definately give them a shot.
 

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Discussion Starter · #12 ·
Thanks, guys, I'll take that info under advisement. I'm still relatively new to the tubular game and all I know is what I've either read, been told, or observed personally. The only technique I'd ever personally used before owning my own is old school gluing. I figured I'd experiment a bit, but here I am back with the tried and true. I'll keep an eye on them as the XC season progresses.
 

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Hardtailforever said:
'Crossers and roadies have been running sealant to prevent and repair flats in tubulars for years, and it's the use of sealant in particular that makes tubulars a viable option for mtb racing. See Leonard Zinn's explanation on Velonews for draining sealant from tubular tires. I also use Caffe Latex in the tubulars and have experienced no issues with drying up so far. I anticipate these tires will wear and be retired from race use before the sealant is dried up.

bad mechanic, tubulars are superior in performance to a tubeless clincher simply because the whole tire casing can flex and conform to the terrain in a way that is impossible with the clincher interface. For an illustration of this concept, check out GEAX's website and look at their "MTB Tubular" benifits page. There's a neat little graphic that I think shows it quite well. Remember the first time you rode a normal clincher converted to tubeless with sealant? Going from tubeless to tubular is at least as dramatic in terms of increased traction and cornering, but without the possibility of rolling the tire or burping at lower pressures (tape issues aside).

In addition (and the primary reason this thread is being posted in the weight weenies forum), the rims can be built both stronger and significantly lighter than any clincher rim simply due to the complete lack of a bead seat on the rim.

Mayor, I spoke with several cyclocross racers, in addition to several tire reps, and all of them suggested using the Tufo tape as a first layer. It's my understanding that the concern is not the strength of the tape itself but rather that of the adhesive interface with the tire, which in this application would be completely replaced and covered by layers of glue. I can see how using a pourous material, such as Velox rim tape, soaked in glue would make for an incredibly strong bonding surface, though. Thanks for the tip.
my devil's advocate analogy Q is this, "Why aren't there then tubulars on motorcycles and automobiles?"
 

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cale399 said:
my devil's advocate analogy Q is this, "Why aren't there then tubulars on motorcycles and automobiles?"
There might be a ton of advantages to run tubulars...

But for offroad riding if there's NO PIT NO TUBULAR ! Racers with short tracks and passing the pits every once in a while this might be okay but beeing stranded out in the bushes with a puncture is definitely not what i would want. With tubulars there's no DIY help possible and it pretty much means you have to walk home if that happens.

I'm using tubulars on my roadbike, i really love them. BUT there too i chose a tire that gives me a secure ride, not the fastest. I am using Conti GP4000 tubulars as they offer superb puncture resistance while offering still good rolling resistance. I also tried Vittoria tubulars and while they definitely rolled faster they also got me 2 punctures within just a couple of days. And since the Vittorias don't come with a removable valve core you couldn't even fill in some sealant like you can do with the Contis which usually still gets you home...instead i was forced to call someone to pick me up by car...nice;) So off came the Vittorias even though they were still like new.

Same story when a friend of mine used a set of Dugast tubulars in Tuscany...1 hour into the ride he got a flat that couldn't be fixed. He had to call his wife which came to pick him up somewhere in the bushes of the italian tuscany....while the rest of our 8 man group had a little smile.

And i am still curious to see any real rollingresistance numbers of tubulars vs clinchers as on roadbikes the newest clinchers definitely roll faster than the tubulars! That was always the BIG argument for tubulars that they roll faster but today this isn't the case anymore. I personally have found that on a MTB the rollingresistance is a huge factor.
 

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ok there may be some but to put it in perspective on regular, expensive top notch performance car i.e. Porsche 911 GT3, Ferrari Enzo etc. etc. dont they have regular tires?
secondly, I like your mentioning the pit-stop perspective that is where these tires may be fine but when I am racing a 50/100 miles race in the North GA mouintains or just doing an epic training ride in the middle of no-where this does not seem to be the best application
 

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I don't think that anyone would claim that a tubular is the best option for a 50 or 100 mile MTB race or trail riding in general. They are for XC racing and in that capacity they are simply the best.

And to Nino, Vittoria tubulars most certainly do have removable valve cores. (At least everyone that I have used (Evo CX and GC). A couple year ago they did switch some of the tires to a style where the actual valve unscrews from a little "nub" right at the tube. For those I just put a regular valve extender on it (I'm using all of mine on deep section wheels, so they all get extenders anyhow).

I always liked Conti tubulars too, they hold up over the long term well. But I don't like their lack of a latex tube and the ride isn't as good as a Vittoria or Veloflex.
 

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Hi quality tubular tires for MTB have very high thread count cotton or even silk casings. They are much more supple than even the best clincher tire out there. As such, they perform better at lower pressures, conform to the trail better, and corner like nothing you've ever ridden. They have tubes inside (almost always latex), but they are sewn into the casing, so you can't pinch flat them (easily).

You obviously can't run a tubular "tubeless", something has to hold the air. OK OK, some of the POS Tufo tires don't have a tube in them. They are made differently, being completely sealed rubber. They have stiff sidewalls and ride like trash (all tufo tires, IMO). They don't have the supple cloth casings of the nice stuff.
 
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