I was wondering if a Dyno Jet Kit would be worth the money for a 250ex? Can you notice a power increase? Thanks for any replies.

 

Depends on what kind of modifications youre doing and how mechanical you are.
What have you got planned? remove the air lid? K$N filter? freer flowing Exhaust?
I just bought a bunch of jets from dennis kirk and they were 2.99 each. Theres no instructions, just jets. And thats why the kits are more expensive, they have instructions.
If you do the trouble of full exhaust and full filter treatment, and jets...you might squeek out a 10% increase in power, which is somewhere around 1 horse, if youre lucky. I suppose it could be felt, but it might be cheaper to sell the 250, and upgrade to a used 300ex.
Just changing jets isnt gonna do much, except maybe make a cold start easier. In order to get your moneys worth from the new jets, youll need to free up the intake and exhaust too.

 

Personal opinion from a person who was in EXACTLY the same situation. I was 16, and had a 250ex. I'm by no means a power monger, but the first thing I noticed was a go-kartish whine out of corners and the crappiest suspension on the face of the planet. So, I vowed to work my royal heiney off for a summer and go to a showroom floor 300ex. Get it at the right time and right place. I bought at the model year's end, and drove a ways to get a deal. For my effort I now have adjustable preload, way crisper response, and I can easily pull wheelies in 3rd. Now thats before I took advantage of the amazingly large aftermarket market for this bike. My intake/exhaust combo is well planned and properly jetted after rigorous testing. I know all you asked about is a jet kit, but if you really want more power, don't expect a jet kit to do it for you. And even after you have the setup you want, STILL don't rely on a jet kit to get you dead on. You'll be on the playing field, but lots more toying with needle shims, mains and pilot screws are required. What you're really paying for in a jet kit is the knowledge that gets you close. By the way, I'm not ripping on your bike. That got me into the sport and served me reliably through some idiotic maintanance mistakes. Still chuggin' along piloted of my brother. It doesn't really matter what you ride, as long as it's not imaginary.

 

Dynojet comes with a new needle which is key for maintaining consistency throughout the full RPM range. For most, a Dynojet takes away huge amounts of frustration and makes it easy for a novice to easily rejet and be near perfection without relying on dyno runs, etc.

/Jon