The FMF SST pipe made a big difference, more power with more of a hit. I was amazed at how much different the bike was (but... I was comparing it to a stock pipe that had a good-sized dent - maybe that's was why it felt so different). I had no luck with the Power Now (it helped the bottom and throttle response, but took away all the top end power and forced me to dorp the main way down to a 350 at one point), and I had the Moto Tassinari V-Force reeds, but recently went back to stock and prefer that - It just seems to run / jet cleaner with the stock reeds - and when I say stock I mean Boyesen super stock. The Honda reeds chip. I didn't try the Boyesen dual stage reeds because I wanted to go back to stock, which I like.
I had someone tell me to advance the timing a little - I tried that, and went back to stock - that was making the bike knock.
I tried different gearing for MX, but always went back to stock. Gearing it down helps with bottom end, but makes the power in each gear too short.
The suspension on the bike is great, I never had mine re-valved, but I did put on the RG3 top clamp. Did it take away vibration? Maybe a bit, but my bike doesn't seem to vibrate.
I never got bottom power out of the bike without ruining the power. The bike is good and powerful and fun to ride - I just use the clutch in every corner.
That's my experience - get it jetted to your area, keep good tires on it, and have a blast. I am currently selling my bike to get an RM250 - that's the mod to make if you want bottom end. But I love and will miss my Honda.
Thanks crash 142.I just bought a new 2003 cr 250.haven't had a chance to ride it since it is winter here in Canada.I was happy with my buddys 2002 cr 250 so I got a good deal on a 2003.Was going to buy the cr 450 but went with the 2 stroke for know.Good to know what works and what doesn't with out spending the money and time.
I have to disagree with his statement. The bike is fun to ride stock but once you mod it you will see a big difference. Save your money on a pipe and get it ported by Eric Gorr (mo better). There are plenty of posts on this bike in this forum. Do a search. Bottom line is, it is all in what you want out of your bike. I also had my forks done and I love them, much better than stock. It's your choice. Enjoy the bike.
One thing I would suggest is get a good chain. The stock sprockets are good, but the chain is not and will stretch and prematurely wear the sprockets.
I've never had a bike ported, so I can't comment on that.
Also fix the seal between your airbox and airboot, and the seal between your airfilter and airbox - PC makes a kit (kind of expensive). I used their 2 neoprene pieces, but not their red aluminum airboot ring - I found the stock one worked perfect, where the thicker PC aluminum one would vibrate the top screw out.
Once you start riding it, you will notice a lean spot just off idle which causes it to surge a little. Put in the optional 38-70 needle to fix that. I also put in a 35 pilot jet to make it run crisp on the bottom. If you ride on any tight MX tracks, you will want a 50T rear sprocket so you can keep it in 3rd most of the time, just tap the clutch coming out of turn and it will light'em up. Hope this helps.