- The Saguaro tires came mounted to a set of aluminum rims, which also fly the Geax colors. Though they aren't particularly exotic, the rims have wide, flat beds, which help the tubulars adhere securely. Currently, the rim is not listed on the company's website, so this may have been a limited run for Geax's tubular tires. Photo: Spencer Powlison | VeloNews.com
- The Geax Saguaro has moderate side knobs, which do well under standard cornering loads. The tread pattern is somewhat open on the side, giving the fast-rolling race tires a bit more versatility. Photo: Spencer Powlison | VeloNews.com
- A bit reminiscent of the old Hutchinson Python, the Saguaro has a row of alternating blocks in the center. All of the knobs are low and fairly stiff, which plays well on fast hardpack terrain. The tire's profile is also round, which helps you ease into a cornering lean. Photo: Spencer Powlison | VeloNews.com
There’s a certain risky extravagance that comes with riding a pair of tubular mountain bike tires. Like blasting across the U.S.-Mexico border in a Ferrari F50, driving 120 mph with a trunk full of sequentially numbered $100 bills. If you make it, it will be glorious.
To review a pair of tubulars like the Geax Saguaros, we have to recognize the fact that any mid-ride puncture is irreparable. No spare tube in the world will help you.
Cyclocrossers have always been tubular devotees, but they don’t venture into the backcountry aboard tires that are essentially impossible to repair. Most of the time, they pass a well-equipped pit every couple of miles. Worst case scenario: they end up drinking a beer with their mechanic, pondering a flat tire.
If you thought it was annoying to seat tubeless tires, get ready for the excitement that is tubular gluing! When it comes to mountain biking, a bulletproof glue job is essential. Our friends at The Service Course here in Boulder, Colorado helped ensure the tires were safe and secure.
The Geax casing — made by Vittoria — is particularly “handmade,” as the labeling says. It’s nearly impossible to get the 29×2.0” tire to run perfectly true. After a lot of work during gluing, there were still wobbles in the tread. It’s not noticeable on the bike, but neurotic mechanics will be perturbed.
The 630-gram Saguaros are wisely equipped with removable valve cores. We immediately took a weight penalty and loaded the tires with sealant to have a fighting chance if we punctured. Though we often use Stan’s, we picked Orange Seal this time, which the company claims doesn’t clump or dry up in the tire. It also contains “Nanites,” small particles that may help seal larger punctures.
Having ridden our fair share of tubular ’cross tires, we knew the Saguaro would be capable of low pressure. So we tinkered a bit, and ended up riding at around 17-18 psi in the front and 18-19 psi in the rear (rider weight: 150 pounds).
Ride a mountain bike at these pressures, and it feels like an entirely different beast. On loose dirt, the tires shimmy and drift beneath you, especially under pedal force. At first, it feels sketchy. But it didn’t take long to figure out how to push the tires, and the loose, drifting qualities became fun, even playful.
The Saguaro’s tight, reliable tread pattern certainly helped these tires drive predictably on everything from hardpack to loose, loam to slimy roots. The treads are low-profile, but with such low pressure, the tire seemed to wrap itself around any trail obstacle.
Low pressure isn’t without drawbacks. We hit the rim on practically every ride — often quite hard. For those of us conditioned to dread the pinch flat, this is disconcerting. However, we never had an issue. Also, with tires so soft, the bike tended to smear and squirm on hardpacked berms and jumps. We quickly learned to stay away from the pump tracks.
But why tubulars?
Our overall experience with the Saguaros was positive. Throughout 250 miles of trail riding, they were trouble-free. We even got confident enough to tackle a 25-mile point-to-point race, something that could have easily deteriorated into a hellish trail marathon had the tires failed.
That being said, the Saguaros, and tubulars in general, are impractical. Whether you’re aboard a road, ’cross or mountain bike, tubulars have been and will always be the provenance of racers. These are people who — possibly under the influence of excessive Mastik fumes — are happy to sacrifice easy repairs and inexpensive replacements in the name of performance.
If you don’t know, you’ll never know. Racers who have tasted the ride qualities of off-road tubulars will want more. If you’re still scratching your head, don’t sweat it. At least you’ll never have to worry about explaining why there’s a bike rack on your F50 when the Border Patrol catches you.
Pros: Great ride quality, fast, solid tread pattern.
Cons: Setup, impending flat tire doom, not possible to easily swap tires for changing conditions.
The Bottom Line: Tubular mountain bike tires are about as niche as it gets, but we can see why world championships have been won aboard this old but proven technology.