2010 YZ300

CHASSIS / SUSPENSION
Suspension (Standard) Front: Independent double wishbone with Showa shocks, five position spring preload adjustability 00.0 inches of travel
Rear: Pro-link fully adjustable single Showa Shock 9.1 inches of travel.
Suspension Front: need to add oem specifications
Rear: need to add oem specifications

I think its missing something.

I would like to see a test on this yz285 vs. the ktm250sx with the 300cc top end on it. Stock then modified comparisons.

Why not call it what it is? A YZ285.

And only $7599!

I know huh! 7500 for a 450 killer. Save $500 and who knows how much more in a years time of maintenence. This would be a holeshot machine with the handicapped bikes in the 'open' class.

i sold Boyesen 2 YZ250's that they put big bores in and worked their motor magic on, they love them. TONS of power.

I rode a 98 or 99 RPM YZ300 that was built for Craig Davis and it felt like a smoothed out 500. Absolute unbelievable power from crack of the throttle until you felt like shifting with the lightness of a 250. Amazing bike.

"hey kid, nice kx80.", "It's an 85!"

The Service Honda machine is actually a 295cc motor built by E. Gorr. The head uses a traditional gasket vs. stock o-rings like you can use with a 265, 275 or 285cc jug, but the rest is the same.
Bore it, port it, grind it, coat it and then abuse the shit outa it!



Not sure about the Showa boingers though... I think SH needs to cane their web guy!!



Powerseal built me a YZ285 top end back in Nov. 2008 (bored, ported, PV grinding and head work) and it's still going strong. I've re-ringed it once and have ridden the hell out of it. It's a pretty brutal machine if you advance the timing 1 degree and run race fuel. I'd gladly put it against anything in a 200' drag race before I run out of gears.



Next time I split the cases it's getting 1-5 gears from a WR426 and will then be perfecto! I still prefer my Husky 300 for technical single track riding, but if I'm going to the dunes or dez the 285 always gets the nod. It's a bad machine!

If it is anything like this, it will be a blast to ride.

When they do the big bore kit does the Power valve get taken out and how does that affect it ?

Powervavle gets ground down to clear the larger piston.

I had a 52 hp yz265 that TZ built and it was a beast. My 4-junk is still easier to ride as no vibes and less wheel spin. That said I will buy another YZ before they stop making them,

Bro that cylinder has some nasty scrathes in it, and don't tell me their cross hatchings.

Because the piston goes sideways instead of up and down? The camera is super close to the top of the cylinder, thus shows the honing. It's just the angle of the light and camera hitting.