Boyko Racing head/cylinder work & experience

brademan76 · Post by **brademan76** » 01:07 pm Jun 02 2025

After seeing Chuck78's thread about squish and etc (viewtopic.php?t=26022) I decided to send my wife's 1994 KDX cylinder and head off to Ted Boyko at Boyko Racing in Southern California to have whatever work done he thought would help improve (most importantly) bottom end power/"tractorability" and wherever elsewhere in the powerband that he could. My wife tends to run low and slow, especially on technical uphills where any extra power that will keep her from stalling the bike will be nice to have.

Ted told me that would mean cutting down the cylinder base on a lathe 0.01", milling the head, and doing some port and polishing work. He would also hone the cylinder (no discussion of re-plating) and size for correct size Wossner piston. While it did end up taking a little while longer than anticipated- I had to be a "squeeky wheel" after not hearing anything for a month after it arrived at his shop (not a big deal as it wasn't prime riding season)- he quickly completed the work and got it shipped back to me. I was very happy with the quality of work, and Ted was really nice, communicative, and enthusiastic about helping provide as best a riding experience for my wife as he could. He also has a thing for older bikes and thinks KDX's are great.

After putting the bike back together, I did have to richen the Lectron's metering rod 1/2-3/4 turn to get it dialed in- I also upgraded to a RAD valve from stock cage at the same time. I thought it ran great while I tooled around on it in the yard and got the new piston worn in. On the trail, I've been really suprised at how low of RPM my wife can run it up some steep spots without it bogging and stalling. I've thought it runs great the few times I've had to take it up some really technical sections for her. Not quite the pep of my RB'd 220, but definitely money well spent.