KDXRIDER.NET

I have acquired a 2005 220. The concern that I have, is the lack of bottom-end torque. It bogs down low and has a very hard hit mid and top end.
This is the present set-up when purchased.
FMF Turbine Core
FMF Desert Pipe
Boyesen Rad Reeds
Open Air Box
13/47 gearing
Cleaned and verified working KIPS
150 MJ 45 PJ ( dropped the pilot to a 42 and the bog worsens)
The needle is in the 2nd position.
Altitude rode in 5500 to 10500 (Colorado)
Tight single-track trails.

Any help would be greatly appreciated.

Hmm, your PJ is already too big in my experience. I ride at 2000 and run a 38pj. I think the main might be step to big as well but only testing will tell. Follow the jetting guide here on the forum to sort out your jetting after figuring out what is wrong. Your current jetting isn't the issue but a symptom of it.

First thing I would be looking for is an air leak since you said going smaller of the PJ made it worse. I would check the condition of the reeds, the jet block gasket in the carb, a compression check, and possibly a leak down test. It wouldn't hurt to confirm the timing is set to the stock spec but I doubt anyone has played with that.

I had a similar situation and found I was jetted too lean on the pilot jet. Bike would lean bog off idle with a 40 pj if the air screw was more than 1/3 turn out. Went to a 42 pj and it runs perfectly with air screw at 1.25 turns out.
Point being, jetting is critical! Follow the steps and take the time to get it right.