Technology is everywhere and even in as simple sport as cycling as its core is full of technology from wireless shifting systems to smart suspension systems and electronic motors. I've been riding enduro mountain biking and with going downhill in rocky trails it's good to have some protection for your tires and rims. Puncture prevention systems like Schwalbe Procore and Deaneasy Tube+ helps you to avoid Snake Bites and protect your rim from dents with two air chambers but you can also do it simpler with foamlike solution such as Huck Norris.
The challenger: Huck Norris
"With Huck Norris the rocks gets the punctures when you ride!" - Huck Norris
Huck Norris is a relatively simple technique inside your tubeless tire to protect from Snake Bites and dents to the rim. It looks like it's made from normal foam sleeping pad but the material (chemically crosslinked polyethylene) is specially developed for MTB use with actual scientists. It has "three times the impact energy damping than anything commercially available". The installation is as easy as it looks, you just put it inside your tubeless tire and there's no need for modifications or glue. Huck Norris also makes it easier to mount the tubeless tire without compressor as it gives the tire a shape which helps the bead to set.
There's not much more to said about Huck Norris. Just set it up, inflate the tire and you're done. It weights 70g on 27.5" size and 77g on 29" size, is suitable for 21-30 mm internal rim width and you can use it with alloy or carbon rims. Also Plus size and Fatbike versions are coming soon. Huck Norris is made in Finland and you can get it from Vuoripyörä's webshop for 50 euros for a pair packaged with a mud guard. For more information check out their webpage or Facebook.
Riding with Huck Norris
Huck Norris was just recently released for general availability and I've used it for about month. As you could figure, it makes the tire a bit more stiff than without but the extra protection and especially the possibility to race on mountain bike enduro style tracks with the air pressures you want makes it great. No need to over inflate.
But as usual, even Huck Norris can't protect your rims when the going gets tough although it still might save your race like it did mine on Santa Cruz Enduro Series race at Levi. The special stages were fast with hidden rocks and hits were unavoidable. As you can see from the picture I dented my rim but Huck Norris absorbed the impact so that the rear tire was saved from flat and I got to finish the race. I think I broke it on stage 5 and still drove the 7 stages left. For the curious I had Maxxis Minion DHR II 29x2,3 (3C MAXX TERRA) with about 1,5 bar air pressure on Roval Fattie 29 rim with 29 mm inner width.
The dual-champer system: Schwalbe Procore
After the Enduro MTB race at Levi where I had broken my 29" rear wheel I had to switch to my 650b+ wheels for the next race. Not what I would've wanted as I don't like racing with 2,8" tires. As the Huck Norris is not yet available for Plus sized tires I had to get something to protect the rear rim from the rocks at Santa Cruz Enduro Series race on Tahko. Luckily my local bike shop had Schwalbe Procore system and sold me one separately. A bit more weight to the rear but also less punctures.
Schwalbe Procore is a dual-chamber system, tire-within-a-tire anti-pinch-flat system. It consists of a small-diameter tube and tire that is inserted inside of a conventional tubeless tire and pressurized to over 80 psi. The insert acts as a secondary impact cushion that allows you to ride with lower, or at least the optimal, tire pressures without being concerned with pinch flatting and protects the rim. It also helps to prevent the tire from 'burping,' which is when the tire bead is pushed inboard of the edge of the rim and allows air to escape from a tubeless tire.
Procore is available for 26", 27.5" or 29" rims with minimum of 23mm internal rim width and for minimum of 2,2" tire. Compared to Huck Norris the weight is considerably more, 220 grams per wheel and it also adds it to the place you don't want it: to the wheel, increasing rolling mass. Procore system (one pair) costs about 200 euros.
Schwalbe's Procore kit consists of a pair of tubes and inner tires, a roll of high-pressure rim tape, tubeless sealant, air sleeves, tire installation lubricant, dedicated tire levers, and decals to outfit two wheelsets. I used my existing rim tape as kit's rim tape (for 25 mm) was useless for my 29 mm rims.
Although the Procore looks complicated and I had heard rumors of installing it, in practice it was fairly easy as the installation instruction show. Pinkbike's review of Schwalbe's Procore has also good explanation of the installation but the review otherwise is somewhat a mess. The only hassles I had was with keeping the tire sealant inside while getting the bead to set as I was too lazy to empty it. And one thing I forgot to put in place was the small clear patch over the valve hole as an additional seal but it worked anyways. I was in a bit hurry to install the Procore so I don't have any pictures of it. Why test your new equipment beforehand when you can test it at the race.
Riding with Procore
I have only rode with Procore couple of days, practice and race at Tahko enduro MTB event and some local trails and it does what it promises. Although Tahko race had serious rock gardens my plus sized tire and rim survived without flats or dents whereas other riders had problems. Or maybe I just drove too slow (finished 32th) as I wasn't exactly comfortable with 2,8" Nobby Nic tires with 1,2 bar pressure on slippery rocks and grass. Without Procore I would've inflated it to at least 1,5 bar. Anyways the extra protection was welcome and money saver.
Procore seems to be good system as it doesn't affect the tire behavior and adds protection but they say in the Internet that the high-pressure inner tube adds strain to the rim, loosens spokes' tension and there has been a notable number of documented issues with carbon rims. With aluminum rims the issue not so clear and very few aluminium or carbon rim manufacturers have officially approved it but they haven't recommended against it either. As I didn't have a spoke tension meter when I installed Procore I can't say whether or not the Internet is right. Time will tell.
Huck Norris or Procore: use both
Schwalbe's Procore, in my opinion, is a good solution for protecting your tires and rims while allowing you to ride with lower tire pressures. Compared to much simpler Huck Norris, the more technical dual-chamber systems adds extra protection when needed but also additional weight which isn't an issue when going downhill but makes a big difference when it comes to accelerating, and for long days on the pedals. But I would think twice before using Procore with carbon rims whereas Huck Norris is suitable for any rim.
When I get my 29" wheels running again I will put Procore to the rear and Huck Norris in the front. Best of both worlds.