Fat, Cushy, Grippy EMTB Plus Tires

The duke

Active Member
#1
I recently purchased a BH Atom X that came with 2.8" x 27.5 plus tires (Nobby nics). I used to mountain bike in the 1990's with 'standard' MTB tires on a hardtail. The fat plus tires are amazing! I've got the pressure low (20psi). The grip blows me away....so much better than standard 2.25" tires. I cling to slanted trails & roots. I climb up things I couldnt walk up and braking is so strong! It also soaks up the bumps on my hardtail....it almost feels like I've got suspension.

Since I've got a motor, making rolling resistance less of an issue, I'm wondering how fat EMTB plus bike riders go with their tires? What's available and if I keep going fatter, will my grip keep getting better and will my ride keep getting cushier? I'm thinking 3.25" if I can find it. Anyone with any experience? Are there any drawbacks?

Also, when on the road, how tight do you guys turn on plus tires? How far can I lean it over? Grip on road feels insanely sticky but I'm scared I'll push it too far and have the bike slip out from under me!
 

JRA

Well-Known Member
#2
In the early days of plus tires becoming available Vee made a 3.25 called the Trax Fatty. Probably still available but you might want to check your clearance for a wider tire especially in the rear triangle. I personally don't like too wide a tire on the front as it seems to affect steering as I am used to but in the back it makes good sense to use a higher volume tire.

Having a wide enough rim with a plus tire is as important as the tire width on the label. I feel an inner width of 35mm to be about perfect and can really make a 2.8, which it seems has become the go to size for the industry over wider 3.0+, can make a big difference on how the tire will perform and what psi you can run it at, especially in regards to absorption and traction.

It's good to be cautious of mtb type tires on the road as they can be unpredictable. There are models that will do well on both but usually they have less aggressive outer knobs.
 
#3
Anyone with any experience? Are there any drawbacks?
I run no less than 3.8" on the front (on a non-fatbike), and the feeling is superlative. I honestly don't care that the wheel on the back is a meager 2.6", this is just too good, regardless of bicycle. It's not for everyone though, since it's not a particularly cheap set-up.

Here's how you do it:
  • Buy a narrow fatbike rim. Like a 65mm Sunringle Mulefut or Surly Rabbit Hole or hell, maybe even ZTR Hugo. Don't buy an 80mm rim unless you have very narrow brake calipers. How narrow? Hard to say in advance. XT seems to fit, but I wouldn't risk it.
  • Lace this rim to a 110mm hub. This is highly unorthodox, but works just fine.
  • Get the Fox 34 "PLUS" fork. There's only one. Be careful not to mess up and get an ordinary fork, this "PLUS" model is fairly unique. This one is expensive.
  • Get a 3.8" fatbike tire.
  • Bonus points: get a reliable 203mm rotor, like Shimano Ice Tech. Why? Well you now have a heavy front wheel, you need more stopping power. Plus, a larger rotor keeps the caliper away from the widest point of the spokes.
This set-up is the awesomest set-up. Interestingly enough, it works with both 26+ and 27.5+ wheels since the fork fits 27.5/3.8 provided of course you don't go overboard with too wide a rim.