Maxxis Minion FBR 4.8" Thoughts

My Salsa Mukluk came stock with Maxxis Minion FBR 4.8" tires on 80mm rims. I don't recommend this combination.

What's a fat tire for, anyway?

Why run a fat tire? 

Well, over the past several years, folks have been experimenting with bigger tires for all kinds of riding. Roadies have upgraded from 23mm to 28-32mm tires. Gravel bikes boast bigger and bigger tire clearances every year - 35mm, then 40mm, and now 45mm is a common upper limit. Road Plus is putting 650b wheels for 47mm and 2" tires on these bikes.

Mountain bikes have been doing the same thing. 2" tires used to be beefy, but ordinary mountain bikes are sporting 2.4-2.6" tires, and plus bikes push that all the way up to 3". Cyclists will tell you that the bigger tires offer more grip, traction, comfort, and suspension - and they're right. The costs are weight and (at a certain point) rolling resistance.

The more tire you have, the looser terrain you can ride. With a sufficiently large tire, you can go on loose sand or deep snow. And that is what got people riding fat bikes - the desire to roll over some ridiculous snow bank, or cruise along remote beaches.

Once fat bikes became popular, people tried them on dirt, and they liked them. Fat tires provide some level of suspension and are lighter than forks and shocks. The extra grip and traction make climbing relatively easy, and it's real easy to pick a line when you can just plow through everything.

So, you want a fat tire because you're going to ride on snow or as extra traction and suspension on dirt.

Measurements

On the 80mm rims, the tire measured out to about 4.3". That's a far cry from the advertised 4.8". Folks running them on 100mm rims report sizes around 4.5". Unfortunately, their advertised weight - 1,620g - is pretty close. With a bit of sealant still stuck on the interior of the tire, my tires weighed in at 1,690 and 1,740 grams.

Snow

The Minion is a weird snow tire. Indeed, it isn't labeled or advertised as a snow tire at all. Here's the tagline from Maxxis's website:

The Minion FBR is a rear-specific fat bike tire designed for trail riding. It shares the look of the Minion DHR II, but is optimized for fat biking. The Minion FBR features well-known, proven side knobs for cornering traction and ramped, paddle-like knobs down the middle, minimizing rolling resistance and maximizing traction in all conditions. (source)

The Minion handles groomed snow OK. I would typically run 3-5psi in these conditions. The traction is good, but not great. There were a few occasions where the tire would wash out in deeper or looser snow. This resulted in a crash.

On ungroomed snow, the Minion is not so great. At 3-5psi, the tire doesn't offer much float. When you drop the pressure to 1-3psi, it starts getting extremely draggy. It exhibits some strong self-steer. And, worse yet, the snow sticks to the tire, and then traction goes to shit.

Maybe 100mm rims would do the job here, but folks report much better luck on 80mm rims with Surly Bud/Lou tires or the Maxxis Colossus.

I wouldn't buy the Minions again for snow riding, but of course not, because they're not snow tires, not by Maxxis's marketing nor my own experiences.

Dirt

So, it's a 4.8" trail tire. How does it perform?

At 1,620g, it's a chonker. The significant weight and size give it quite a bit of rolling resistance. This is a slow tire. Is it technically capable? Yes. It is. The tire has immense traction on dirt and works quite well for technical trail riding without any suspension.

Here's the rub. At 6+psi, the tire is too bouncy. It'll ricochet off the dirt and jolt you around. Bring it down to 3-6psi, and you've got a good bit of suspension and grip. But you also get squirm, self-steer, and less predictability in cornering. This is a tricky balance to play, and I usually found myself frustrated with the tire on the trail. When the tire was dialed in for a certain run, it'd do fantastic, but the next section of trail would benefit better from more or less pressure. It was difficult to get a compromise that had me enjoying the entire ride.

Again, I have to wonder if the rims are to blame. 100mm rims should allow the lower tire pressures without the squirm in cornering and help with self-steer.