1. Alignment marks
2. Rear rear axle nut and safety pin. The torque value for the rear axle nut for your 2008 Kawasaki Ninja 250R is 72lbs. The size in standard is 1". It's not a perfect fit but the 1" socket did the job.
3. Adjustment bolt and lock (adjustment bolt is on the inside, the outside nut is just to lock it once you're done.

You can get by without using a rear stand, but it's highly recommended.
* Remove the safety pin and losen the rear axle nut. You don't need to remove it
* Losen the lock nut
* Align the chain using the adjustment bolt and the alignment marks. I typically give the chain about 1-1.5" slack. A lose chain is better than tight chain (I was told).
* Make sure NOT to move the adjustment bolt when screwing the lock nut back, and use some sort of thread locker like Loctite.
* Repeat the same steps on the other side, and tighten the rear axle nut back to 72lbs of torque once you're done with both sides.
* You're done!

Thanks for that write up, but I'd be worried about screwing something up if I tried to align and/or adjust my ninja 250 chain. I think I'll let my dealer handle that one.

good advise. one quick question. when i align them on the sides nuts. am i suppose to align them to the + sign. or a lil bfore that? my chain was loose before and got it fixed on the spot. its feelling a lil loose again. so i wanna fix it and get that over with