Dry dirt over a hard base: This application would be hard
terrain, which basically means if you step in the dirt and you don’t
leave much of a shoe impression, it’s considered hardpack. Hard-terrain tires ride more on top of the dirt (like your shoe impression),
relying on tread footprint for traction. Hard-terrain tires have
shallower tread depths, which reduce rolling resistance, reduce
weight and provide a uniform footprint at all lean angles. They
typically feel fast and light on the pedals. The downside is the tread
spacing is typically close together, so if the dirt is too loose, the
tread may not clean out very quickly and can clog easily if the dirt
Mixed—loose, loam, rocks and roots: This application
would be intermediate terrain—soft-enough dirt to leave a shoe
impression, but not so deep that you sink into it. Intermediate
terrain is the most popular category for MTB tires. It’s basically
the do-it-all tread. It may not be perfect on any one type of terrain,
but taking into consideration the variation in intermediate terrain,
the tread is designed to perform very well. Intermediate treads
are designed to provide a balance between low-rolling resistance,
traction and tread cleaning, and typically have somewhat tall
tread depths. They are designed to dig into dirt, find traction,
provide predictable traction on rocks and roots, and self-clean.
The downside is that intermediate tires tend to have softer rubber
compounds (higher traction), which typically wear out sooner.
Soft dirt, deep loam and mud: This application would be
wet, muddy terrain. It’s the type of dirt that if you stand there long
enough, your shoes begin to sink in. And when you pull your shoe
out, dirt is clinging to the shoe. Mud tires have tall knobs with wide
gaps between the knobs. They’re designed to dig into any type of
loose, loamy, wet or muddy terrain. They also self-clean efficiently
with each tire rotation. It’s always good to have a set of mud tires
in your garage or race vehicle for wet weather. If it’s muddy, these
tires are like cheating.
MBA: How do you feel about the plus-sized and fat-tire
movements? Which riders would benefit most from using those
FS: In my opinion, the fat-tire movement has slowed. Yes, there’s
still a place in the market for fat-tire bikes, but I believe they will
head back to what they do best—and that’s snow and deep sand.
It’s no secret they appeal to a special type of enthusiast and, in the
proper application, are fun to ride. But, they have their limitations.
In my opinion, the plus-sized tire market has a bright future for
the weekend enthusiast, weekend warrior and maybe even the
weekend pro. These bikes are fun to ride and provide a really good
balance of performance, weight and handling with mega traction.
MBA: Will plus-sized or fat tires ever be race-worthy outside of
the Fat Bike Nationals?
FS: I don’t see the fat-tire market going crazy on the racing side,
but plus-sized tires I do. Look at the bikes the plus tires are coming
on. They are totally performance-driven and are way more fun to
ride than fat-tire bikes.
MBA: What tips and tricks do you have other than lining the label
up with the valve?
FS: Not sure if this is a tip or a trick, but one thing that always
seems to come up when I’m speaking with riders, customers,
dealers, etc., is a tire’s life cycle. It’s obvious a rear tire wears down
quicker than a front tire, and it’s easy to see this wear evidenced by
a disappearing tread depth. Most people install a new rear tire and
they’re happy; however, what people don’t realize is that the front
tire is wearing too. The tread depth still looks good, but the casing
structure is worn out. Over time the casing gets soft, which reduces
puncture resistance and flattens the tread profile (arc), which
affects handling and cornering traction. Also, the shoulder knobs
Break out the hot iron:
Frank isn’t afraid to modify
a tire to get what he wants.
He’s been known to clip
knobs to find the right tread
for the given terrain. His tool
of choice is a hot iron that
quickly and cleanly cuts
through the rubber.