A while ago a friend of mine bought a wheelset on ebay that came with some Specialized Clutch SX tires already installed. He didn't think much about them, figuring they were OEM throwaways, but out of curiosity he left them on for a ride and was pleasantly surprised. A few more rides and he was even more impressed. After his glowing recommendation I decided to try a pair of these tires for myself, inside you can read about my impressions.
This is Specialized's "freeride tire" and is 2.3" wide and uses their SX casing. The sidewalls would be considered a 1.5 ply, much tougher than a standard single ply. Weighing in at 970 grams, it is a bit heavier than your standard single ply tire, but at least 200-300 grams lighter than a full DH tire. If you're interested in saving weight, your wheels and tires are the most beneficial place to do it. The Clutch SX uses a dual rubber compound, 45a on the side knobs and 50a on the center knobs. That's pretty soft, I figured that would give them great traction, but lessen the tire's life. More on that later. Size wise, the 2.3" Specialized is very similar to 2.5" Maxxis tires. I run all my tires tubeless on Stans' strips. Bryan runs Mavic tubeless rims. Both setups worked well with the Clutch SX. We both use compressors for inflating tubeless setups so I can't speak for the ease of setting them up with a hand pump.
These tires hook up like glue in dry conditions. If you're wondering about grip, check out the sidewall flex in this photo. That's at 30psi, these tires are gripping hard and you never get the feeling that they are rolling over. I had these tires on my bike when we did the Race at the Ranch preview
and found them to work very well in the dry, dusty conditions.
Wet Roots, Rocks and Loam
The Clutch SX works really well in wet conditions, the rubber is very soft and clings to wet rocks and roots like gum to the underside of a desk. Riding in the mud doesn't pose any issues, although they do seem to pack up quickly (while simply rolling along), but they clear out quickly as well (once back up to speed). I found them to be very predictable when starting to drift and rarely found myself in an uncomfortable situation that I wasn't expecting.
Here's a few shots of Bryan rolling some wet roots, rocks and loam. Sometimes you just have to know your tires are going to be there for you, and the Clutches never let him down. Braking on the wet rocks and roots didn't phase the tires, there's tons of traction. I'm assuming this is mostly due to the soft rubber compound and siped center knobs. The same goes for off camber roots and slopes. The softer side knobs grip like there's no tomorrow.
The tire is tough enough that you never have to shy away from any terrain, big or small. Here Bryan launches a burly line.
Climbing, Rolling Resistance and Tire Wear
If there can be a con to these tires it might be that they are slightly slow rolling. It's a bit noticeable on longer fire road like climbs, but I'll gladly take that trade off for the wicked traction they offer. Increasing the air pressure lessens the rolling resistance, but reduces traction as well. I run them around 30-32 psi and found it to be good on both characteristics. But if there's yet another pro, it would be tire wear. This took me completely by surprise since I thought for sure that the soft compound would result in quick wearing tires. I've got a couple of months on them so far and they look like new. Bryan has a full season on his set, he figures 40+ rides and they are still in fine shape. See below for a comparison photo of a brand new Clutch SX compared to season old tires on either side of it.
Brand SX in the middle with season old tires on each side
To summarize, Bryan and I both really like this tire. It is definitely an extremely good "do everything" tire as long as you are willing to sacrifice a bit of climbing efficiency for great traction during the descents. They exhibited great traction in all the conditions we had them in, and we really can't find anything worthy of a complaint. If you're building a light freeride bike and can't afford to cut corners on reliability or deal with pinch flats, these are definitely worth checking out. MSRP is $60 USD and considering the fantastic wear we're seeing so far, I'd say it's a bargain.
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