1st Look – Panaracer Fat B Nimble 29+

By : Ken Blakey-Shell


Recently the Panaracer Fat B Nimble 29×3” tire became available. Even though I was hearing rumors of the tire being a bit undersized for the 3” label, I have to say that I was so enticed by the specs I was seeing that I ordered up a pair ASAP. The big characteristics that grabbed me were the low claimed weight (765g), lower price than a lot of other 29+ options ($79.99) and a tread design that looked similar to the 45NRTH Husker Du (a personal favorite 4” tire of mine for dirt).

When I got the tires I was pleasantly surprised to find the claimed weight being accurate. My tires weighed in at 755g and 778g. Both numbers are well within the normal weight variation from tire-to-tire making the 765g claim very credible.

Chupacabra left, Fat B Nimble right

Chupacabra left, Fat B Nimble right

The rumors I had heard about the tire not being a true 3” tire were accurate. Unlike the Knard, Chupacabra, Trax Fatty and Chronicle which are all within 1-2mm of the same casing size, the Fat B Nimble clocks in at about 4mm (0.14”) smaller than those tires. On my 35mm rims (30mm inner width) I measured the casing of the Fat B Nimbles at 69mm (2.72”) and a bead-to-bead measurement of 178mm (comparison, Knard is at 188mm). This smaller casing makes for a slightly smaller outer diameter than the other options and I measured approximately 0.2” smaller diameter for the Fat B Nimble than the Chupacabra.


The tread is made up of smaller, well spaced blocks that contain a variety of sipes, ramps and steps. Knob height is consistent from center to edge at approximately 4mm tall. This makes for a very rounded profile and also contrasts with a lot of other existing 29+ tire options. Pretty much everything else in 29+ world that I have measured have fairly short center knobs and taller side knobs. I haven’t hit any mud yet but it looks like it should a fairly versatile tire that can handle a range of conditions.


Chupacabra on top, Fat B Nimble bottom

One of the first observations I made when handling the Fat B Nimble is how supple the casing feels. It is far more flexible than the Chupacabra or Chronicle and similar to my 120tpi Knards. Having supple tires is great for allowing the tire to better conform to trail irregularities improving ride quality, traction and decreasing rolling resistance but the flip side is generally a lack of durability. It is way too early have any real experience with casing durability and these tires but it is something to think about if you are considering being an early adopter of these tires.

The tires seemed to go tubeless ok but by no means perfectly. I couldn’t find any indication from Panaracer that this tire was designed for tubeless applications so going tubeless may be beyond what is was intended for. This is why I am a “professional,” putting my body on the line to test products for the fat-bike.com audience. The bead was a bit looser than some of the other specifically tubeless compatible tires like the Chupacabra and Chronicle but I still got several reassuring “snaps” as the bead locked into place at around 15-20 psi. I also had to fiddle with them a bit to get the sidewalls and beads to fully seal but nothing too onerous. One thing I am not liking is that it seems like there is a bit of wobble in the casing of both tires but I am going to try a few more rims, some Uncle Dick’s Bead Slip and a few other tricks to make sure that it is the tire and not something I am doing, a weird rim/tire interface… Full report to follow after more time fiddling with the tires.

Initial ride impressions are positive. I swapped out the Chupacabras I have been running most of the spring and now have about 100 miles of time on the Fat B Nimbles. Drive traction is a little less than the Chupacabra but still way better than regular 29er sized tires. Maximum cornering traction is similar in that it isn’t as good as the Chupacabra but way better than regular 29ers. The tire breaks free and regains traction in a very smooth and predictable fashion. This characteristic has made it really fun to ride because it is easy to “feather” at the edge of traction, drifting corner after corner in a really relaxed fashion. Even though I am sliding around a lot more than when I ran the Chupacabras, I have been seeing some of my fastest downhill times of the spring while riding these tires. I am guessing the faster times are just because I am having so much fun flirting with the edge, I am spending more time going fast at that edge of traction envelope. The decreased volume (compared to other 3” tires) has only been noticeable in the softest sandy spots but otherwise has been no big deal. I have enjoyed the supple feel of the casing which seems to contour to every little irregularity in the trail.

My guess is that this is going to be a very polarizing tire with 29+ riders. Early indications are that it has some very compelling aspects (low weight, low price, versatile tread design) while also having some possible negatives (questionable casing durability, less than advertised size). Personally, I am excited to see a new 29+ tire available that differentiates itself from some of the other offerings currently available. Another aspect of them that interests me is that I think they are just narrow enough to fit on my 29er which has been sitting in a corner of my garage gaining dust since I went 29+. I plan to test out how these tires do on slightly skinnier rims and will report back if this tire may open up some doors to the plus-curious riders that currently don’t have plus-specific bike.

1 Comment on "1st Look – Panaracer Fat B Nimble 29+"

  1. Just wondering if you had a quick tubeless reliability update on these? I’m looking at purchasing these because they look pretty sweet. Thanks.

Leave a comment

Your email address will not be published.