The UPS man arrived with a bunch of XR4 tires and we were rightfully excited. The tread pattern is much different from the previous generation as it is more modern with a simple, blocky and more open style. The 26er tires are called XR-4 and the 29er tires are 29-4. The ’4' refers to their trail/traction abilities on a 0-4 line with the XR0 being an ultra lightweight xc race tire and the XR4 being an aggressive all mountain tire. Continue reading →
Strengths: Relatively light for a large, high-volume tire (in Team Issue) Works well for loose over hard and rocky conditions.
Weaknesses: Weak sidewalls, poor bead strength. Hard to get to seat/seal with air compressor, impossible with floor or hand pump.
Bought a new pair of the 29-4 original design for the Niner WFO that I was building. Airing the first tire up after mounting, BOOM ! The tire blew off of the rim. What a mess ! Stan's everywhere, ringing ears and a sore hand from the explosion. OK, I must have over-inflated it. Well, I was extremely careful with the second tire and only 'pulsed' the air into the tire so as not to over inflate it. At around 35 psi, the tire blew off the rim with the same result. Mounting to brand-new Easton Haven wheels, so not an issue with the wheel/rim. The pressure range on the tire is 30-50 psi, so I was not exceeding the maximum pressure. I compared my digital air-pressure gauge with my Bourdon-tube style analog air-pressure gauge and they matched, so not an issue of an inaccurate pressure gauge. Eventually, I did manage to get both tires mounted - after covering them with a blanket while inflating for safety - and rode them for a few weeks (about 100+ miles) without any problems. That is, until the sidewall rolled when I pushed hard into a bermed corner and I went over the bars. It felt like suddenly hitting a large rock, but the berm was hard-pack with no rocks. The tire did not burp, the entire tread just rolled under the rim. Probably my fault, as I was running the front tire at 26 psi which is 4 psi under the recommended range. The kicker is that when I got home, I slowly added some air to the front tire, and BOOM ! it blew off of the rim. OK, I've had enough. Concerned that if I was flying down hill and hit a rock hard enough, the tire would blow off of the rim from the sudden pressure change, I removed the tires. I then mounted a new pair of Bontrager XDX tires (non Team Issue) which sealed quickly and never blew off of the rim while seating the bead, even when quickly inflated to the maximum pressure of 50 psi. The good people at Bontrager had no interest in admitting to a poorly engineered tire when I contacted them regarding the issues I had with the 29-4's. Nor did they have any interest in replacing the tire under warranty. They did not even know that they had two different revisions of this tire. I had the old style which was apparently the original release, and Bontrager has just recently released a re-design of this tire. Clearly there was an issue with the original or it would not have been re-designed after only one season. I won't be buying Bontragers again.
Strengths: Wider than a Purgatory 2.4, much better grip then the 29-3's. Rolls pretty decent. Can carry some speed on the corners, take the bumps and rocks with no issues. I run mine tubeless with Bonty Rhythm Pro's and they fit perfectly.
Weaknesses: The knobs need to be angled a little more for more side/leaning bite. At times at a high speed corner, i have to either slow down more of not lean as low so the tires don't lose grip. Compared to the Slant 6 or Nevagal, these tires can use a little more side bite. Straight on bite is pretty good.
These are a huge upgrade from the 29-3's. I can appreciate a good gripping tire with traction which these tires provide. It is a great all around tire and would recommend them to anyone who needs a 29er that will both roll and grip very well. Can it roll better? Yes. Can it grip better in the corners? Absolutely. But for the price, you get the BEST tire for the price point IMO.
I have the 2012 29-4 Team Issues. I've always had an issue with Bonnys and their ability to telegraph washouts. These are no different for me. You can go from a hairy turn to laying on the ground staring at the sky before you even know what hit you. I can't say they are bad because they perform fairly well, they just scare me at or near the breaking point.
Date Reviewed: May 31, 2012
Strengths: huge tire both tread and volume. This is a tall and wide tire. Enough sidewall flex to help grip without compromisng steering confidence. amazing durability, especially for a tire with such great grip. This is way bigger than the Conti x-king 2.4.
Weaknesses: 800g is not light, but this is a huge tire. I could not get it to fit on the rear of my ventana el capitan without rubbing, but fits great in front. Not super fast rolling, but I have older tread pattern.
buy this tire if you are looking for something more than a fast rolling tire. Blows away WTB and geax tires that I have used. A bit better grip than panaracer ranpage with way better wear. much more volume than a tioga psycho 2.25 which is a solid tire.
a Cross Country Rider
Date Reviewed: May 20, 2012
Strengths: Somewhat lightweight, minimal rolling resistance and lots of volume. Pretty good grip.
Weaknesses: Weak, thin sidewalls and overall not very durable.
I've been using Bontragers tires for about 18 months now. First used the 29-3's then the 29-4's. Lots of hope but after riding many miles I can say they don't hold up on the ST here in the northeast US. The sharp rocks we ride on tear these tires up fast. I liked the weight and the grip but it ends there. About 3 months ago purchased some Tioga Psycho Genius tires and have been running on my fav trails but decided to change my front tire to a Bontrager 29-4 which ripped a sidewall on the first ride but held air still and then on the 3rd ride punctured the tread.
Crap is all I have to say. My Psycho Genius' have no knicks or holes after 3months at about 1/2 the price.
I've only used they on 1 ride, but here in the desert they roll pretty fast, I have mine set up tubeless on arches, easy to set up. Side walls seem thick which explains the weight. I'll update my review once I get a few more rides in..
Strengths: Weights are close to what is advertised, awesome traction in a variety of conditions, can be run tubeless, can be had with 120 tpi casing
Weaknesses: Weight is a little heavy but they are big tires
These are the new, redesigned 29-4's. They are way better than the old style, and are the best tire I used to date. The roll well, have great side bite, and are predictable on slick roots and rocks. I run them tubeless in a set of Velocity Blunts using Bontrager's plastic strips and valves. This system works extremely well. I have been running this system with Bonty tires for about 3 years without any issues. I only buy the expensive versions of these tires since I prefer the higher thread count (more supple) and the lighter weight. The extra ten bucks is worth it. When I aired these up, there were several pin hole leaks that quickly sealed up with Stan's. These are the first tires that I've had from Bonty with this issue. This is not a deal breaker for me, as they still sealed up very easily, and I haven't had a problem with air leakage in the couple months that I have been using them.
Similar Products Used: Bontrager FR-3's, Brontrager 29-4's (old style)
Bike Setup: rigid 29'r ss
a Cross Country Rider
from mechanicsburg pa
Date Reviewed: December 14, 2011
Strengths: sidewall and wet weather traction
Weaknesses: weight for expert model
Got tire when i ripped 2 CG panaracers on one ride. It was all the lbs had in stock and saw weight was close to 900grams. Figure it winter what the heck.
Rode excellant as rear tire through rock gardens that I haven't cleaned in a long time. Put it on my flow front wheel since it was only tubeless tire i had and it great in front as well.
Got an team issue for next season to try out. I love the 2011 models have such great sidewalls and don't rip knobs like the wtb bronson tire. I feel this tire can be a bomber tire on any terrian. The tire cleans mud excellant and grips is excellant in rocks and mud.
Similar Products Used: panaracer rampage, weirwolf wtb, geax gato for 2.3 size tires
Bike Setup: hard tail salsa el marchi 2011
a Cross Country Rider
from Dripping Springs, TX
Date Reviewed: September 5, 2011
Strengths: Big, burly knobs, traction
Weaknesses: none yet
i've had the ACX jones on the rear, the MK 2.4's front, litlle traction at best on the central TX dust, leaves, rocks and boulders, these 29-4's could have been named Bulldozers. Traction to spare and a huge footprint, they also feel heavy and slow, a trade off I'll take for traction, neither weight weenie or racer. Even pushing the bike the difference is remakable, feels attached to the ground. I've got the Expert, heavier than the team, don't know aout the sidewalls yet, only a few rides so far.