When coop first posted the link to the KDX site,I went over and registered so I could have a look at the "hybrids"
Keeping in mind the fact that I have reasonably extensive experience with a 220 my bro in law bought new and I modified for him-I have a good idea how they run and can be made to run.
Anyhoo,my first thought with the hybrids was: that's a pretty cool,easily done project that gives the best of both worlds.
After a little more thought it occurred to me-why would you bother?
There is nothing magical in a KDX engine other than fact that it is an ordinary,everyday,older 2t engine done as a woods/trail set up-which is what makes it such a good woods bike.
I've always liked 125's and what I really liked about my 02 SX was the fact it had a full sized chassis.The japanese downsized them previously and KTM followed suit in 03.Though I'm only 5'10",I find most of the more "modern" ones squishy.Previously,the only real difference in a 125 and 250 was the lower cradle but I guess the theory was to cater to a smaller rider coming up from an 80.
It's sometimes hard to get more power but it reasonably easy to get less and adjust the delivery to your liking-regardless of what you ride.
If I was a Kawi fan(insert shudder here
),I'd take a KX250 and detune it to replicate the KDX engine.This would give a better balanced bike with a manageable engine and modern day ergo's and suspension.
In the case of my YZ,I loved it on the track but found it was too abrupt in the low speed greasy,rooty,rocky goo.A twitch of the throttle in this stuff had the rear wheel lighting up and spinning sideways.
For me,the solution was to use a dial gauge in the plug hole to ck the stock timing(it was too far advanced due to production tolerances)and set it to what it should have been.After a little trial and error,I ended up setting it one degree retarded.
I also shaved down the ramp on the throttle(again,trial and error) so I have a longer pull but more importantly,it doesn't ramp up as quickly so is much more manageable off the bottom-but still has full power when you twist it open.
As it is,it suits me well.I could have added a flywheel weight as well but don't see the need and I wanted the quick snap when necessary for logs,rocks,etc.
You could also go with a thicker base gasket or double up(though this changes port timing-maybe good,maybe bad depending)play with squish,higher tension reeds,power valve adjustments,bigger carb,different exhaust,flwheel weights etc.
The bottom line is,it's all easily done and will make a much more rideable bike-and you won't have the "gooberiness" of a hybrid.
As I said,I still think a KDX engine in a 125 chassis is a cool project-just rather pointless.
