We added one tooth to the rear sprocket (from a 49 to a 50). This helped
smooth out the jerky low-end throttle response by helping us get above it.
GEARING FOR THE MASSES
The 2017 CRF450 has a herky-jerky
power delivery at tip-in. This erratic power
delivery turns quarter-throttle solutions
in corners into a series of unsyncopated
lurches with each blip of the throttle. MXA
test riders found that the best way to avoid
the sporadic low-end power delivery of the
2017 engine was to run the engine harder
and higher in the rpm range. This worked
well for fast riders, but not for Novice and
Vet riders. Given that the Honda CRF450
works best in the midrange and well above
its cranky low end, we geared it down
one tooth (from 49 teeth to 50 teeth). This
helped slower riders ride the bike higher in
the powerband at low speeds in ruts and
off-throttle flat turns and enhanced the pick
up for fast riders. Every test rider preferred
the 50-tooth over the 49 for general racing.
CHAIN GUIDE ISSUES
The stock rear chain guide has a two-piece rubber glide block inside the aluminum carrier. The previous CRF450s had a
one-piece glide block. The problem with the
two-piece glide block is that it flaps around
and drags against the sides of the rear
sprocket. Mechanically, it’s not an issue,
but cosmetically, it scratches the sides of
the rear sprocket and leaves ugly drag
marks, especially on anodized sprockets.
The quick fixes are to super glue the 2017
chain block to the inside of the aluminum
chain guide or order last year’s chain block
from your friendly local Honda dealer. We
elected to replace the complete chain guide
with a TM Designworks Factory Edition
SX chain guide. It is almost indestructible,
comes in several colors (we chose red) and
is a replace-it-and-forget-it product.
The 2017 CRF450 chain guide has a two-piece rubbing block. It flaps
around and scars up the rear sprocket (see above).
The best chain guide fix is to switch to a TM Designworks Factory Edition
SX unit. It is light and bulletproof.