I am turning wrenches on a friend of mine's 2005 KDX220 and I have opined that we can "open up" the green monster and get him a wider power band and more power. It is a brand new unit I found for him for $3000.00 so it does not need a rebuild. I am focusing on the reeds, the pipe and the silencer. I have already installed a JD Jetting Kit and resolved hard starting - I am not however, married to staying with the JD kit as I progress through enhancements.

The riding type is technical single track and this is the first motorcycle he has owned - I talked him out of riding 4-wheelers for safety concerns since we do mainly serious hill climbing. This bike will not need to be set up for racing. He weighs 175 pounds.

With that backdrop, my question is can someone give me a good tried and true set of alteration suggestions for tweaks that are conservative and provide for good radeability with no poor side effects? I have read and been told pipes make a difference and they make no difference. Same thing with the silencer. I think it is generally agreed that upgrades on reeds make sense. I have been told to can the carburetor and get one off of a KDX200 (larger CFM) before I do anything, then go to a new silencer. The owner has little patience for tweaking trial and error unlike me, so when I spend his money, I really need to hit the mark more for the convenience factor than the spend factor.

Since he wasn't used to a clutch, I installed a RevLoc and he may be moving away from that now that he can ride the bike without drama. Obviously, for the expense of the RevLoc he is not afraid to have me spend his money, he just doesn't want to be inconvenienced with the tweaking "process" so if we can move to tried and known improvements, that is what I am looking for advice to do.

The result I'd like to obtain is more power down low, a wider power band, and more overall torque/hp over the powerband spectrum. Sounds like an unrealistic target, but some say the KDX220 has all of that corked up inside of it. What say you???

Here's the best place to start.

http://www.rb-designs.com/

The 220 has a smaller carb to give it more low-end power than the 200. Also, the stock piston in the 220 has been known to grenade if run excessively at high RPMs.

fmf gnarly woods pipe for low end- rb carb and head mods for power overall- remove snorkel-think about a wiseco piston- boyesen rad valve maybe- front fork springs at least

I myself have a 220. After extensive research I went with the Pro Circuit pipe and Boysen 607 reeds. The bike has significantly more power through the entire range, more so on the top end. From everything I have read, and people I've talked to, the FMF woods pipe doesn't work well with the 220, but does for the 200. The FMF desert pipe works on the 220 but you will lose low end power. Piston swap is good insurance.

http://www.dirtrider.net/justkdx/

Look under tech tips.

^^ What he said ^^^

silencers on these dont really make a difference. a pipe will move the power around, and reeds are a plus. if he really wants to spend money on the bike, head mod and p&p, or kx fork swaps are popular.

A pipe will ADD power, not just move around, as some MX bike pipes do.

Almost everyone I have read a post from who has a KDX220R and went with the Desert pipe reported NO low end loss.

Your quick and easy power gain is going to be a pipe. Everyone can change one in 15 minutes, so everyone seems to do it or want to do it.

At some point, getting the suspension tuned for him is going to let him better use the power it does make. If you guys are just wanting power, let him get a KX500. :)

KDXGarage said:

I rode my KDX with a desert pipe and my buddy's with the woods pipe back to back. I couldn't notice any low end difference, but my top end was WAY better.

The low end loss with the desert pipe IS noticeable at elevation. I live at 7000ft and ride up to 11,000 ft, and going with the Gnarly desert did cause me to lose a little at the bottom (but, gained everywhere else)...right now I am trying make up for some of this by going with FRP torque ring.

rodrigeo said:

I live at 4,000 and ride up to 9,000 and haven't noticed any loss. What's your jetting at? I'm at a 38, JD blue needle on 1st clip (lean) and 145 main. I live in Canada, so it's either really hot or really cold here. My jetting seems to work great for either, albeit a small adjustment of the air screw never hurts depending on the day.

I'm at 40 and 150 with a Sudco CEK needle at #3 (2 away from leanest). Based on what you are saying I could go even leaner on the pilot and main. Your settings are worth a try...probably when it warms up again. How's the spooge on your settings? I get some, but very little that shows up on my swingarm below where the silencer mates to the expansion chamber. Like a drop or two after about a 6-hour ride.

Slick_Nick said: