Editor’s Note: Our European correspondent, “c_g”, has filed his first report in his review on the Geax Saguaro tubular mountain bike tires.
GEAX SAGUARO 29er tubulars – out of the box and mounting: by “c_g”
What is all the hype about the tubular tires in the mountain biking world about? “SUPERIOR GRIP, UNRIVALED COMFORT, PROVEN RELIABILITY” – These are the claims by GEAX on their MTB specific tubular tires, which soon will be released in the 29er format. I have been lucky to receive a pair of those tires plus the fitting rims before their official release – (Yeah, sometimes it is plain cool to be a tester. J
Here is a short recap for those that haven´t followed the last Euro posts. The GEAX SAGURAO 29er tubular tire is to be seen as the bigger twin brother to its 26” sibling. It shares
1, The ultra high count cotton casing with 290 tpi (most MTB tires are between 60 and 120 tpi !!!)
2, The (almost) exact width of 2.0” (50,8 mm measured at 2.5 bar) and
3, The well established SAGUARO tread pattern. The casing is sewn up with a latex tube inside, creating a airtight system by itself. (strange to be able to pump up a tire before you ever mount it J).
The two tires I have received weighed exactly 740 g and 746 g. Like I stated before, GEAX was not wanting to make the tire the lightest around but aimed to get riding characteristics and reliability right. Did they? Let´s see when I get to ride them – but first let´s mount.
Fig. 1 all the ingredients for a great wheelset – partly built
Note that GEAX´s mother company VITTORIA has been in the leading edge of tubulars for roadies for decades. But despite this vast experience the translation of this technology into the MTB segment (and especially the 29er format) has not been an easy one, shown by the long time from first spy shots in 2008 up until the final release just now.
Oh yeah, before I get into the gluing/taping controversy – just one more word on the tires Design and Technology: The GEAX SAGUARO tubs are 99 % hand made (basically just the tread pattern isn’t, as it’s done in a standalone mold and then hand glued to the casing) – with about 8 hrs working time on a single tire. The GEAX tubulars are hand sewn at the inner side and the tread is hand glued (as opposed to vulcanizing):
“The real advantage of this technology is flexibility: not having the casing heated up along with the tread (which the vulcanized ones are), thus keeping it away from heat stresses and thread rigidities which occur due to it, resulting in the most flexing and supple combination (casing itself + tread) possible. Vulcanized tubs are mid to low end in the road range… (cheaper and faster way of manufacturing).”
(by S. Bressan, designer & product manager of GEAX)
But there is a tiny downside to this technology, too. Apart from the more elaborate production it means there is a small seam protruding ever so slightly all around the contact area. Since this interface of two surfaces is what ensures the positive bond between tubular tires and rims, some rim manufacturers go as far as to design a minor groove along the center of the rim. My sample rims didn´t … but more on that later.
Fig. 2 The inner cavity of the rim is supposed to resemble the tire´s curvature in the best possible way.
GEAX also pointed out that the casing material is cotton (rather than nylon) which makes them much more compliant. While nylons can be a bit lighter they are more elastic and less flexible, translating into a much clincher tire like roll-over character and less comfort. Also Nylon can only be vulcanized and has an overlap of plies with strong glue in place of the hand made sewing of the cotton ones.
My sample tires had one minor imperfection: That is a minor unevenness in tire width near the valve. After speaking with Geax’s technicians it turned out to be a minor defect due to pre-production model and will not affect the production models. In my sample it is only detectable in width, not the rolling outer circumference and so I suspect it won´t actually affect the tires´ride.
A Word On Rims & Build: The rim provided to me by GEAX is made by AMBROSIO and weighed ~ 410 g at a 25 mm width (beware, there rims seem to be currently unavailable). Rumors are there will be an EDGE composite rim (said to be even grooved) introduced alongside the tires´ official introduction at Sea Otter Classic and there are the FRM tubular rims mentioned before (see here), which should be available by end of April.
I will spare you with details of the wheel build. The only difference in lacing the wheels was that the rims do have a very large inner cavity, making it extremely easy to drop a nipple inside the rim (some form of nipple guide is strongly advised).
My particular wheel set consists of Shimano 965 hubs (oldies but goodies) and SAPIM CX-Ray spokes (those frequent readers know: I dig them) and ended up at 3144 g for the set (1485 g front; 1660 g for the rear) – without cassette, and rotors. Not the most weight conscious but for my intended riding just right.
Mounting: Once the wheel is built you need to fix the tire to the rim which can be done in two ways. To create a safe connection between tubular tire and rim you can either use the good old way of gluing by some special cement (e.g. GEAX MASTIK´One), which is really messy and time consuming (unless you are an expert at it ) or by using a double sided adhesive tape (like offered by TUFO).
The taping version is a very fast, clean and simple way but out of my own experience creates a weak bond. You simply peel off the protective tape on one side and fix it to the rim (leaving the tires side still covered). Then you put on the tire, inflate and adjust for a balanced and wobble free rotation (very vital and best checked on a stand) and then simply peel the tire facing seal off between the tire and rim (that is if you have considered to have a small end sticking out at the end ). After you’ve fiddled around with it the first time, it becomes a thing of 5 minutes and you are set. When riding at higher pressures (2 bar and higher) I have been successful with tape only, but generally I apply some glue – to be on the safe side.
Fig. 3 +4 The double sided adhesive tape is a easy and mess-free way of mounting the tire to the rims – it is near invisible and is rideable immediately after mounting; but the bond isn´t the strongest.
The gluing process is fairly elaborate: First you apply a thin layer of glue on the rim, then let it dry overnight, then another layer on the rim and a layer on the tubular tire (after having cleaned the base tape with just soapy water), let them dry for 10-20 minutes, mount the tub slightly inflated, center it and then pump it up to max. . Then you need to let the glue cure for min. 8 hours and you are ready to go.
But beware – the special glue (by some manufacturers aptly called “Cement” is the some of the stickiest and ugliest form of glue you have ever worked with. Chances are when you have gotten the tire mounted and sitting wobble free in place the entire rim, tire will look like my 4 year old´s attempts at handcraft work and much of your clothes will be ruined forever. (I am speaking out of my own hurtful experience).
After having mounted several tubular MTB tires over the last years (all in 26” ), I personally found the best way for me was a combination of both. First I taped the tire to the rim like described (makes for a easy wobble-free installation) and then I would deflate, and apply a small bead of glue along the outer edges of the contact area for the ultimate of bonding. If any of you CX racers and seasoned tubular riders have a better system, please do let me know! I think in this technology we will need to look hard at what the roadies have gained in experience over the past decades.
Fig. 5 This tire was glued only (not the combination method mentioned in the text – upon close inspection you can see lots of glue all over the edges, the rim and the tires. I have been told the experienced roadies can mount tubulars with glue mess free and very fast (apart from curing which always takes hours).
This is what GEAX´s designer & product manager S. Bressan had to say on the taping vs. gluing topic:
“As handmade tubular manufacturer, we always highly recommend to use glue/mastic over adhesive tape to glue tubulars on: Due to the small sewing protrusion on our tubulars (mentioned above), the tape cannot fully adapt to it and fulfill all the empty space that remains between a sewed casing and a flat tubular rim. The glue instead adapts to it and fulfills the groove all the way over the circumference. Other than that, glue strength is also more than tape by chemicals. If you add these two things, you find out that glue is almost twice reliable than tape.”
In the event of having to change your tire, you will have a very easy time separating tire and rim when taped but struggle some time when properly glued. But the same principle applies concerning the strength of the bond that keeps the tire from rolling off. Simply because I have had incidents of tires popping off the rim (mostly when experimenting with tubeless setups) – I had no desire to have that happen to me in my tubulars – so I eventually glued all of them.
Ok, that is done – my first ever 29er MTB specific wheel is ready to prove its worth – stay tuned.
Great article! Glad to see tires enter the 21 Century. Tubeless was just the beginning, this is the future. I guess you can tell that I am really excited…
Whoa, those wheels are heavy!
Feels like I’m back to 1984, gluing the tubulars to Ambrosio rims (hard to get back then too).
RE: Tubular attachment methods – Lennard Zinn has lots of good info about it on the VeloNews website. He posted a bunch of articles during CX season.
This is interesting for sure. Looking forward to your full report. I’m in no hurry to buy tubulars though…I hate paying $50 for tires already!
Those wheel weights HAVE to be wrong. Oh wait… That must include the the tire mounted? Okay, then that makes sense. But you gave the weights before you talked about mounting the tires…
We are confused, please clarify?
Hmmm … you are right the weight of 3145 g is including the tires … and skewers for that matter.
(Sorry for the confusion by stating it before the paragraph on mounting.)
Looks great, I’m really digging this and look forward to those Edge rims, they shoudl be around 270 grams…?
Glueing is definitely the strongest connection. Your glueing looks like rubbish on the other hand. I’m here in the cyclocross heaven (belgium/netherlands), and glue around 40 tubes every winter, and some mtb in the summer also, but after done it a few times it should be a problem to put them on without seeing any glue on the rim or tire after finished. Maybe some on the edge but definitely not on the sidewall.
By the way, weight of the tires looks a lot, but it includes a innertube and valve. so 740 grams minus a 120 grams inner tube (which is light already) is just slightly over 600 grams. That”s not all that bad for a real 2.0 tire.
Let us hear about those tire reviews, we’re curious.
Hi Ninko,
sorry if my glueing is offensive to you . I appreciate your open critizism and yes I fully acknowledge not to be the tubular glueing expert – not at all
.
In this respect we pure breed mountainbiker really have to admit that what is new to us, might well be common knowledge to CX-riders and roadies.
.. but like Imentioned above: Feel free to share your expereince and help us avoid such mistakes. How are you doing it? Care to share?
c_g
That’s a very nice rim weight. Apart from it lacking sidewalls for breaking, I’d have like those in my CX days. 25mm rims as opposed to 20-21mm, should make low-psi riding much easier, with fewer rim strikes and subsequent punctures.
Does it really make sense? I have Geax Barro 29 2.0 tires with 380g and Maxxis Flyweight tubes for 26er with 95g. That makes 475g for tire and tube. I can mount the tire and tube in 2 minutes without gluing and waiting and it looks nice and clean. What about puncturing a tubular tire? Can you change it in the race? I think you would need a spare wheel then but I am an amateur biker and don’t have a support with spare wheels while am racing. Tubular tires are only for pros unless you want to act like one…
You put sealant in it like you would a tubeless tire.
But – once the sealant starts solidifying into boogers, how do you get those out?
@those who question the sense of tubulars for MTB: A tubular is not suited for every use. In CX racing, the advantages are very clear. You can use really light rims, really low pressures, resulting in lots of grip, low rolling resistance over soft or bumpy terrain, with minimal pinch flat risks. Also, racecourses are not that long and there are pit lanes to change bikes or wheels if neccesary.
Apart from the -really- light (carbon) rims, tubeless tires have much of the same capabilities, although a tubular is even better when it comes to low pressures. With regular rims, eventually you dent your bead hooks or burp the tire. For this reason, you cannot use small tires effectively. On a rocky or rooty course, I would have to run too much pressure in my XR1′s, which kind of sucks the ride quality from them. With tubular construction, you can use light low width tires and still be safe, comfortable and grippy.
Yes, with tubulars there is a risk of rolling the tire off the rim, much like the burp risk of tubeless tires. The big difference is that burp risk depends on design, whereas rolling risk depends on assembly method. In other words: That is something you can influence, by following tried and tested glueing protocols.
I could see the general benefit of tubulars for MTB use, but only for XC racing use, where you can ride out a flatted tubular to the pit. As for this Ambrosio/Vittoria combination: It simply is too heavy to make up for the benefits. For me, the combination would have to be lighter than a light tubeless setup, or else I could just use somewhat bigger (but lighter) tires and still be safe and fast. It will have to take a 350gr rim and a 2.0″ 550gr tubular with a semi knob tread to make me consider it.
I wonder if there will be a tubular Geax Barro tire coming along eventually? Since these 29′er tubulars are mainly focused on racing it seems they would want to have that tire, as welll as the Saguaro, out there.
I think the concept is kind of cool but unless im racing it seems like a giant pain for everyday use. Yeah that glueing process sounds painful.
I think those are going to have to have some pretty incredible ride characteristics to get me on them.
OK, so my inner old man just has to call BS.
/rant on
There’s so many levels of wrong to this I don’t know where to begin. I know, it’s an elite level racing item. Still. This is not 21st century technology, it’s 19th century. And yes I have ridden, and pre-stretched, then glued, road tubulars. They do ride nice, but is there an actual advantage? For pros even?
I for one would be very happy if elite levels of mountain bike racing didn’t have pits where you can get a new wheel, and required self support. Remember those days? You could be pretty sure that racing was improving the parts you rode.
/rant off
@t0m: Well, while your sentiments are much like my own, here is the reality of this. Yes- Pro mtb’ers are all over this tubular thing. Once the kinks get worked out, you will see a lot of tubular tires being used by 29″er using pros. The elite racers I have spoken to that have actually ridden a tubular off road claim it is nothing short of amazing. Take that for what it is worth.
Pits, support, and unlimited technology/money from the bigger companies are reality in elite XC racing. That said, there is an undercurrent of racing that isn’t sanctioned and doesn’t play by those rules. Self support is king, and “real” mountain biking happens on a regular basis. The manufacturers can’t/won’t/don’t understand the marketing of it, so that’s why it doesn’t get the mag covers and news coverage.
Maybe we’ll see something good come from that in terms of components and choices.
@t0m I find it strange that you think mtb tubulars are “wrong”. I assume it’s not old man-itis, more just a typical knee jerk, reactionary posture taken to something you don’t want for yourself.
Here’s the deal I’m a CASUAL, 47 yearold sport rider, road and mtb, and I’ve been using nothing but tubulars since I bought my first 10 speed. 19th, 20th, and 21st century technology is what these tires are. They work great for road bikes and now we can get them on our mountani bikes too. I never thought I would go to tubulars for 26″ mtb, I was an early UST adopter and found that technology to work well. Now that I’m finally getting a 29″ mountain bike, for near-Cross type riding I should add, I think tubulars are going to match my needs well. I’m not selling my 26″ full suspension Scalpel anytime soon.
I should add that the pro racers that Guitar Ted mentions above probably aren’t schilling for the industry when they say how much they like the tuular 29′er mtb tires because the fact is it is going to be a a small segment of the market that buys these tires, just like in the roadie world.
They are amazing to ride, but they are not without their pitfalls…
[img]http://farm5.static.flickr.com/4064/4535056275_edcb6cce0e.jpg[/img]
My bike at SSEC last weekend. To be fair I can’t really say whether it was the tyre rolling which caused the wheel to go or whether that would have happened anyhow. There was quite a side on impact. the wheel initially taco-ed and a section of tyre peeled off the rim. I took the whole tyre off, straightened the wheel enough to turn, and the complete implosion happened when riding back to camp. In retrospect I should have straightened the wheel and popped the tub back on.
One thing I did learn was that road rims (they are Reflexes) are not really up to an 85kg rider going flat out and getting things a bit wrong…
Hi Sam,
sorry to hear this – hope you are well.
Sounds like the tire is not to blame. Glueing properly is key to safely riding a tubulars – all roadies agree on that …. and us MTBs just have to learn.
So you rode back on the bare rim? Not sure if a MTB specific rim would have survived that either.
I’m OK, a bit scraped and bruised. Like I said, I can’t say whether the tyre was to blame. It was glued according to the Dugast approved process of multiple layers of glue (mastik) and was properly cured. I think there are two problems. The rims is too light and narrow for mtb use, and the concave of the rim is the wrong profile to have full adhesion across the base tape. The tyres are amazing, but until we have rims which are designed for the intended purpose and to glue well to the tyre then I fear there will be more problems like mine… I’m looking forward to trying the Saguaros, but unless the rim matches the tyre well it could be the end of the road for my my tubular experiments.
Having said that, my Dugasts on Reynolds carbon rims are holding up very well and have now done a number of big rides and races without significant problems. For anyone who doubts the benefit of tubulars and carbon rims, I only need to give them a brief ride on those wheels.
should also have added, yes I did ride back on the bare rim and that’s what caused the complete wheel collapse. It was quite crazy, the wheel went, I bailed over the bars, somehow landed on my feet and walked out of it. The rim was already cracked through in two places after the initial crash and being straightened, so I’m not surprised it failed completely. You’re right that a similarly damaged MTB rim probably would have failed in the same way. However whether a stronger rim would have failed in the first place I don’t know.
… yes, if the curvature in the rim does not match the tire´s diamter (50 mm), than you can hardly ever create a perfect bond between them.
Thus I´d highly recommend to get the correct rims for the tires: The BOR/FRM tubular rims are going to be available pretty soon (for the link see the post on Euro news), AMBROSIO will hopefully become available in the near future and EDGE has just introduced their Carbon rims at Sea Otter.
If I can help out from Europe – please contact GT and he will forward to me.
c_g
I have ridden the Sagauaro in the Tubeless 29er version for over a year and I have been super pleased with the tread. This tire works in various conditions and is very durable (and cheap even!).
My biggest concern is rolling a tubular tire. I have been to countless cross races where I have seen pretty solid crashes from rolled tires. I can only imagine the carnage when you roll a mt tire. Ouch!
Personally I have both tubeless and tubular road wheels and I prefer the tubeless on the road. I think that the traction and pinch flat protection of tubular tires is valuable on the cross bike more so than on the road. I do admit that I hate glue and that I don’t like the tape concept a bit.
I am certain that these 29er tubies will ride awesome. I am even coveting them a little. I just hope that they don’t become standard issue since the average person can’t seem to mount tubeless themselves. (judging by how many people bring them into the shop). The labor cost to properly install a tubular tire should be well over $100 is you account for the time invested. No one is going to be happy to pay that.
Besides glue and tape have ANY manufacturers looked at using industrial strength velcro to attach the tire to the rim ???
I wish you had taken a picture of the tread that was not from the side…
A few more pics of the Saguaro tubular and my experiences here http://singularcycles.posterous.com/finale-24-hour-saguaro-tubs-and-carbon-rims
I don’t know that mounting tubulars is all that hard. I’m a roadie just getting into 29ers. I have had tubular, tubeless and clincher road wheelsets. For me, tubulars are the way to go. Less rolling resistance, higher pressures available, no pinch flats, lighter wheels, best wheelsets are made for tubulars. Also, at least for road bikes, tubulars are safer because you can ride them flat for a while if you have to. That’s something I think of every time I’m on a 45+ mph descent. Flat on a clincher at that speed and you’ve got major problems, likely road rash and broken bones. Flat on a tubular and you can ride it to the bottom.
Once you get the knack of gluing up tubulars it’s fairly quick and easy. One key element some people miss is the right glue brush. I have seen people try to spread the glue on with their finger in a baggie, or with a small artists paint brush. Just asking for trouble! The only brush to use is an acid flux brush. They cost pennies, are disposable, and allow a thin, fairly even and somewhat controlled layer of glue on rim and tubular base tape.
I’d never use the double-sided tape. Just couldn’t imagine it. You’re not going to roll a tubular off a rim if you glue it on right.
So, as I build my first 29er, I’ll be looking at tubular options. Glad to see technology moving in that direction.
after watching a roadie friend turn his thumbnails purple prying tubulars onto the rim, i have to say NO THANKS.
Bubba – As with anything, tubulars do require preparation – pre-stretching. Some brands are worse than others. But, the same could be said about some clinchers. Conti clinchers, for example, can be a beast to get on the rim at times. The same is true for Conti tubulars. Good tubulars, just very tight.
Vittoria tubulars are generally easier to work with, and Vittoria makes the Geax brand. On road wheels I use mostly Veloflex. Some Vittoria, mostly Veloflex. Veloflex tubulars are made in the factory in Italy that used to be Vittoria before they moved production to Asia. Veloflex tubulars go on the rim like butter. No purple thumbnails. I think the same is true for the most part of Vittoria and FMB. Stretch them on the rim for a while before gluing and they mount quite easily.
Also, it gets easier the more you do it. The same is true of clinchers. The first time I did a tubeless 29er rim with Stans it wasn’t easy to get it aired up and sealed. I’ve got it down now so it’s much easier. It takes some time to get these techniques down, no matter what you use.
The benefits of tubulars are many. Top road tubulars use latex rather than butyl tubes, and latex is much more resistant to puncture and is more flexible, resulting in lower rolling resistance. The tread can be either vulcanized or hand glued without the high temperatures associated with clinchers, resulting in a much more supple tire. The tubular profile is round so cornering is better than with clinchers. Shock absorption is better as well. With the stresses spread more evenly across the rim, tubulars absorb rough roads so much better than clinchers do.
Also, roadies who use tubulars have learned something from mountain bikers. That is, a trend of late is to put one ounce of Stans sealant into tubulars, through the removable presta valve. The result, when combined with a great latex tube, is months of flat-free riding. I’ve got two months and about 2,000 hard miles on my current set of Veloflex Carbon tubulars, and they look as great as the day I put them on. Every week I ride past several cyclists pulled to the side of the road changing tubes. Since I switched to tubulars, all of that is a distant memory.