2020 YAMAHA YZ450F
R I D E R E V I E W
P88
As good as the '19 was, however, Yamaha, a
company never known to sit back and rest on its
laurels and give the other manufactures a chance
to catch up, continued with its development of the
YZ450F. So here we are.
For 2020, Yamaha made many not-so-obvious
changes to the engine, chassis and suspension.
When it comes to the YZ's 449cc liquid-cooled
DOHC engine, more specifically its power deliv-
ery, Yamaha felt there was room for improvement.
So they dove into the top-end and redesigned the
head, making it smaller, shorter and more com-
pact. It's lighter, as well. These mods, Yamaha
says, also change the way the YZ handles—for
the better, of course—because these changes
also lower the bike's overall center of gravity.
Keep in mind that, in this case, you're also lower-
ing all those moving parts inside the head that
can make a bike feel heavy and sluggish when
spinning ferociously, so we're talking more than
just merely lowering static weight.
The shapes of both the intake and exhaust
ports are revised, as well, and the compression
ratio bumped up from 12.8:1 to 13.0:1. You can
thank a new high-compression piston and a
smaller combustion chamber for that.
