As is: For 2014, this machine
received the most changes throughout the chassis, engine and nearly
every other part of the machine, and
these changes moved the needle in a
positive direction. This also makes it
tough to evaluate available mods
since there hasn’t been sufficient time
to develop them.
Power-wise, there have been
sweeping changes, all for the best,
though it’s still a bit lurchy and seems
to be light in flywheel feel during roll-on. Suspension is excellent both fore
and aft, so we would leave any
changes here for last. It’s going to
need a larger fuel cell, and we know
IMS is working on one, but the good
news is that the stocker is 2 gallons!
Priorities: Injectioneering has done
wonders with the stock mapping, and
their throttle-body mods have helped
increase roll-on smoothness and pull
throughout the powerband. We have
also tested FMF’s new 4.1 exhaust
system, and it, too, has helped to
soothe and smooth the flow of boost.
Both mods are huge pluses. Right
now, we have a Stealthy 12-ounce
flywheel coming, and since we have
tested Paul Whibley’s GNCC machine
and know how smooth and stall-free
his powerband is, we believe this will
be a boon.
Like most of the Asian machines,
the Yamaha is not gifted with great
running gear for off-road. The rear
sprocket wears quickly, as does the
chain. We went with SuperSprox for
total durability, an RK X-ring chain
and TM Designworks rear chainguide.
Because the YZ comes with a Pro
Taper bar and a changeable top triple
clamp, no changes were needed. We
did toss the grips in favor of Renthal
half waffles, though.
Potential: Last year, the YZ did not
rate that highly. This year, it has
moved up. It starts easier, has wonderfully versatile suspension and only
lacks a smooth, off-road power delivery. Here, Injectioneering, FMF and
Stealthy all help.