More to come with further riding and testing but I just received a pair of the newest 29+ tire and they look like the best option out there, in my honest opinion. I reviewed a few other Bontrager tires earlier this year. The Chupacabra’s are in the same vein as their other TLR (tubeless ready) tires, meaning they are awesome. They mounted up without sealant, even though I added some later. They held air overnight (and for the last few days) with no seepage…at all. That is so rare.
On my first ride with the tires I hit my local 1.5hr loop that consists of some paved road, dirt road, steep and switchbacky and sometimes loose singletrack, and some more fast dirt road. The tires immediately felt glued to the ground. On pavement they are like the Knards in that they have no counter-steer or self-steer or whatever you want to call it. The Trax Fatty’s do. The round tire profile on the Chupa rolls effortlessly side to side making cornering predictable and smooth. The braking and steep climbing traction is much increased over the Knard, probably due to the siped wider-spaced knobs. I was able to grip to the loose switchbacks better than ever before and corner stuff at higher speeds with more confidence. If it sounds like I’m excited, i am! These made the 29+ experience funner, more rail-able, more confidence inspiring.
To add to it all, they’re pretty light at 879g each, in between the weight of the Trax and Knards, in that order. On the Ibis 941 they measured right at 3″ tread to tread. On a 50mm rim they’re wider than the Knards. This may be good or bad depending on your frame and chainline. On my XX1 crankset with a Wolftooth 26t ring my chain was rubbing the tire while cranking in the 42t cog on the steep climb out of Volcano Creek on the Western States trail. I’ll need to increase the chainline with the Wolf Tooth BB30 ring or use the Trax Fatty on back for now. (To be fair, if the rear end on my prototype-yoke-rear-end was stiffer laterally…i wouldn’t have this problem.) Other than that, they fit fine in the Fox Talas 32 fork with about 5mm of clearance. The wide knobs don’t pick up any pebbles (like the Trax did) and fling them under the fork’s arch. Again, the fork pressure has to be 125psi or more so the tire doesn’t bottom out and hit the underside of the crown on big hits, but that’s how 29+ with suspension is these days. I’d love to try the Rock Shox RS-1 though…anyone got 2K i can borrow?
More time on the tire will tell but for me the Chupa’s are by far the best of the 3 options right now. Maxxis’ Chronicle will probably be the next best competition, but with the Bontrager’s TLR sidewall I’m putting my money on the Chupacabras.