The valves are small and somewhat challenging to get right if you are inexperienced. I recommend the tool set from Kawi. At 500 miles I had to set 6 valves at 1000 miles I had to touch up the other two. They were all on the tight side. Carbs need to be balanced, the chain cleaned and adjusted. These are not difficult procedures, the ninja250 siteposted earlier is outstanding. Check all nuts and bolts this little bike likes to vibrate. Good luck and happy riding, the 250 is a little bomb.