Well, they have finally arrived! The rumored TNT and UST Saguaro tires are here at Twenty Nine Inches and ready for testing. Let’s take a quick look at what we have here.


These are in addition to the much loved Saguaro folder tires which will remain in Geax’s line. The tread is identical on these new versions. All that is different are the casings. To review, a UST casing that requires no sealant has not been offered before in a 29″er size until this version of the Saguaro. This tire should air up and stay inflated without sealant due to its extra butyl rubber coating on the carcass. This will affect weight, as we will see in a bit.
The TNT (Tube, No Tube) version is a tire with a specially designed bead and casing that can be run tubeless with the use of sealant. It doesn’t require the extra layer of butyl rubber that a full on UST casing does, so it is significantly lighter.

The graphics on all Geax tires are new for 2009 and are a lot bolder looking than before. There is one other visual cue that is specific to the TNT version. It has grey sidewalls. Geax is known for their sidewall colorings throughout their history in mountain bike tires and now it comes to the 29″er side. The UST tire has a typical black sidewall and is indistinguishable from the folder tire with the exception of the little “UST” seal on the hot patch.


I have said all along that we would not likely see a “true” UST tire in 29″er form due to the extra weight that would be added to a tire casing to do that. Well, I like my crow medium rare, please! However, it is true that the UST Saguaro is significantly heavier than the other versions. Example: Folding bead Saguaro- 660 grams, TNT Saguaro- 770 grams, UST Saguaro- 930 grams. That makes the folder version 270 grams lighter than the UST version. Is that worth it?
I think where we will see the UST version gain some footing is in areas where rocks and thorns are giving 29″er riders fits. The UST casing is obviously thicker, and will be much less prone to damage, it is hoped. That will be a huge benefit to 29″er riders who have been having rocks and thorns ruin rides on a regular basis. Although riders might be wishing for this sort of casing in a wider tire, I think it is painfully obvious where the weight would end up being at for such a beast. Time will tell if that will be accepted or not.
Stay tuned for a First Impressions post coming soon!








Long travel AM 29er usage
Dude – SWEET! And there I go – my MC build Gordo’s arrive next Tuesday, replacing my Flows so I could ride really low pressures on my rigid. Oh well – still have Flows on my Sultan. I ran full UST on Mavic 819s when I had my 5×5 26″ bike….liked the heavy duty sidewalls as they promoted better bottom out resistance at low pressure on the fast paced root strikes in Alabama.
new bold graphics = yuck
Also, I’m not sure I “get” the TNT version. UST, sure, if that’s your thing. The TNT seems redundant though, considering the regular folding version of this tire is one of the better candidates for tubeless conversion of all the tires on the market. Why the extra 110g when the regular version seals up fine and wears longer than most tires?
I just got the TNT version this week. I think the real advantage here is the much thicker sidewalls as compared to a typical tubed type tire. They are certainly heavier than standard tires. I am building some Flow rims up this week and I will try these tires with some No Tube sealant. This should be a very tough setup. Not light though.
So if I’m hearing Jdog right, it might be somewhat of a “light, medium, heavy” sort of deal between the tubed, TnT and UST versions… You can run ‘em all tubeless, but depending on how burly you want/need your casings to be, you can choose your weapon.
As mentioned before though, it’s too bad the “heavy” version doesn’t also come with a bit of extra size/volume to give it a bit of extra burliness. That’d be much appreciated… Say, perhaps something in the range of a 2.4. If you’re going with a 900 gram tire anyway, what’s it going to hurt to add 50 grams and make it a little bigger… a little better??? That’s the question I’m pondering as I look at this seemingly somewhat redundant offering.
jmoote: The thing is, Geax does not recommend that anyone convert the folding Geax Saguaro to tubeless. The bead is not designed to withstand the forces exerted upon it and may cause a cash, injury, or death if used in this manner. To address this, Geax has introduced this TNT version to allow those wanting a tubeless tire, but not a ull on weighty UST casing, a way to achieve this safely. The TNT’s bead is made to UST spec., so it will fit better and not blow off, or fail catastrophically under normal use on a tubeless rim.
The UST casing is certainly a tougher tire, so that will definitely appeal to those having issues with torn sidewalls all the time.
mg: There is a tire coming that I know about from Geax that will address your width concerns and will be offered in folding, TNT, and UST casings. Stay Tuned!
I do understand that tire manufacturers cannot legally endorse tubeless conversion of regular folding tires, but it’s no secret that the great majority of tubeless users are doing just that. With rims like the Stan’s ZTR, there’s little motivation to do anything else.
So my point is that while I don’t expect Geax to tell us to go ahead and convert the regular version, I wonder how they expect the TNT to sell when the folding Saguaro is a known good tire for tubeless use within the end user community.
jmoote
a word of support for GT
being a long standing advocate of tubeless on regular folding tyres with Stans – I had my first and quite monster blow off with folding Racing Ralphs and sealant. My rear tyre blew completely off the rim !
All my fault though
– Shimano UST rims rather than Stans rims – they dont have the same ‘hook’ as Stans rims – a little more pressure than usual (over 30psi due to smooth conditions) and an old tyre.
But this shows that you need to know what you are doing with tubeless conversions on regular folding and those not as switched on as most readers of this forum – and in this case this writer!! – are subject to the risk of not taking enough care. End results are obvious.
Good on Geax for lifting the bar for us 29ers.
I really loved this tire on my first ride with them the other night. This is my 1st 29er tubeless setup.
I ran the Stan’s Flow rims and latex sealant with great result. i ran about 25 psi on both and at 210 lbs I hit the rear rim just once in 3 hours of riding. I know I would have pinched a tube on such a hit.
They seem to roll as fast as the Hutchinson Python but at the same time they offer much more traction.
These will be staying on the bike for some time.
Love em!
j
I would really like to get a set of these in the TNT version. Does anybody know of a shop that has these in stock? I can’t seem to find them anywhere.
I have read that the Stans rims are not meant to be used with the TNT tire, is this true?
Should I be worried using them?
@DanH: Geax, Bontrager, Specialized, and the upcoming WTB TCS tires are all based off UST specs for the bead shape and diameter. So far, Geax and some Bontrager tires seem to be quite difficult to mount on a Stan’s rim. Now Stan’s has introduced a newer BST design with the Crest, and all indications are that these tires I listed are so tight that they are impractical to be considered together. Furthermore; Stan’s plans on introducing the newer BST with its slightly increased bead seat diameter throughout its line up, making Stan’s entire line nearly, or completely incompatible with UST bead spec tires.
It would be best to avoid these combinations, in my opinion, and stick to the systems emerging, (WTB’s), or that are already in place for UST bead spec tires like Specialized’s 2Bliss/Roval wheels, Bontrager’s excellent TLR system, or the like.
Finally, Geax tires tend to be a really tight fit, and I have had troubles getting them on other rims as well. Although Hutchinson and Bontrager TLR rims tend to play very well together.
Stans works better with Conti, Panaracer, and other non-UST, non-tubeless ready folding bead tires. Although, care must be taken, since folding bead tires are not tubeless rated, so doing a non-tubeless tire on a Stan’s rim assumes you take the risk.
Geax TNT’s mount tight, but not so tight to ignore how well they ride.
This is a silly expensive trick, but it works.
When I sell Geax TNT tires, I set them up on some crossmax 29er wheels overnight. This stretches the bead dia slightly and allows for a much easier time mounting the tire.
We sell tons of the Geax TNT 29er tires in our shop, specifically on (current) Stan’s arch and Flow rims.
These tires offer a reinforced sidewall that is very durable. I personally just finished the San Juan Hut to Hut trip from Durango to Moab on this exact setup. I had zero issues. (even on the porcupine rim trail which is notoriously tough on tires). I have now worn out 4 of these tires w/o a single burp or casing tear. Much of this riding was done with loaded panniers offroad.
If the inner bead seat dia was to get any tighter, these tire would be impractical for most people to mount. With the current tires and rims, it is tight but not impossible. You will dent a rim way before you burp a tire. Personally, I would go for a tight fitting tire any day over a loose fitting one.
We sold every sagauro tnt tire I could get this season from our suppliers. When they ran out, I switched to the WTB Wolverine. These mount much easier, are way lighter and roll nearly as fast. They also offer better cornering. The thinner sidewalls are worth noting though When WTB brings TCS to market they will simply dominate in the 29er tubless world .. IMO.
Tires are really a test of good old trial and error. At this point there are huge variance in bead diameter form one mfger to another. (and even in the same brand, Sometimes in the same tire)
These are my personal findings on tire seating using the Current Arch 29 or Flow 29 Mounted with Stan’s Yellow tape. All in 29 of course.
This is just what I have found. Your results may vary wildly. All in folding versions btw:
Geax TNT- Super tight wtih Burly sidewalls (toughest and heaviest going)
Geax- Tight
WTB- Tight enough and ok sidewall toughness
Hutchinson- Tight
Kenda -Loose to Scary loose
Michelin- Loose with tear-prone sidewalls
Maxxis- Loose to acceptable
Maxxis EXO – Tight enough and nice sidewall toughness
Conti- Loose to acceptable
Schwalbe Tubless ready- Tight enough
Schwalbe – Loose to scary loose and mega thin sidewalls
J-