How do you judge hours on a bike?

I completely ignore what anyone puts on their ad for hour readings. 10 hours, 50, hours, 500 hours, doesn't make a difference to me, if the bike looks clean in the photos i'll be inclined to check it out, if it looks like shit, i'll pass.

I couldn't care less about how many hours are on the meter when it isn't guaranteed that the hour meter was installed new. You could have a clapped out 98 cr 250 with 2 hours on the meter because you bought it right before trying to sell it.

I'd look at the oem  hour meter..  If there's doubt look at the footpeg slop, frame bottom for scapes and dings  and clutch cover wear.

Different for me on 2T's, especially like your 2009 that is likely pre-EFI (carbureted) and minimal electronics. Critical thing on a 2-stroke of that era for me would be the frame, cases, and gearbox. The beauty of your bike is that the entire top end and crank can both be completely trashed and it's not a bank-breaker to make nice and fresh again. Even better, you can do it all in your garage with a metric socket set, a descent torque wrench and couple of inexpensive pullers (assuming buying a pre-pressed and balanced crank/rod kit).

Meet at a dealer, most of them will hook up for free (if its a bike we sell and can hook up to we do at least) and give you the hours plus a quick list of what we see wrong!

I always buy blue so I hook the phone app up haha

It doesnt matter. Buying a used bike is a crap-shoot. Ive bought old bikes that were great.  Ive bought newer bikes that were terrible. Ive bought bikes from mechanics that I thought took care of the bike that fell apart. Ive bought from Doctors that mixed gas in the tank and had a rusty chain that ran fine. 

If I’m buying the bike: “hey that bike has 300 hours on it!”

if I’m selling a bike: “hey this bike only has 30 hours on it!”

that’s how I judge it!

I look for a bike owned by a serious racer. Most of the other clowns don’t even know how to change an air filter. Plus, I’m not trusting them if they tell me they do.

my 125 XC had less than 10 hours and the guy had never done anything. No oil changes, no filter changes. Nothing. Never again.