Boyko Racing head/cylinder work & experience

[brademan76]

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.

20250224_154612.jpg (3.48 MiB) Viewed 6620 times

IMG_1427.jpg (3.37 MiB) Viewed 6615 times

IMG_20250602_111529 (1).jpg (2.21 MiB) Viewed 6620 times

[brademan76]

IMG_20250602_111529.jpg (2.28 MiB) Viewed 6619 times

IMG_20250602_111528.jpg (1.59 MiB) Viewed 6619 times

IMG_20250602_111528 (2).jpg (1.67 MiB) Viewed 6619 times

IMG_20250602_111528 (1).jpg (2.16 MiB) Viewed 6619 times

IMG_20250602_111508 (1).jpg (1.32 MiB) Viewed 6619 times

[SpruceItUp]

Looks great!
I'll probably have to get some work done machining-wise on my next rebuild, but that's still quite a ways from now.
I have a couple questions if you don't mind: I've been thinking about a lectron for a couple of my bikes, but I was unsure if they fit on an E series KDX. It seems you have one fitted, is there anything special you have to do to fit one?

I was also wondering which one you bought. The website says that the pro 38-40mm one fits the KDX, but that confuses me as the KDX has a 35mm PWK on it stock.
I tried emailing a week ago but I haven't gotten any response.

Thanks!

[brademan76]

Usually they're pretty good at answering questions.

Mine on my E and H are both original 34mm style models with the metering rod. It's a tight fit for sure but I didn't have to do any grinding to frame or anything.

Again, Chuck78nhas done a deep dive on the newer billetron version of the lectron carb here viewtopic.php?t=25967

Of course this is on the H series bike so a little different, but probably not enough that you couldn't make it work on an E.

[billie_morini]

brademan-- this is a very cool story! The photos are great, too! Thank you for sharing. billie

[billie_morini]

Oh, brademan, who / how wad the cylinder replated?

[SpruceItUp]

Usually they're pretty good at answering questions.

Mine on my E and H are both original 34mm style models with the metering rod. It's a tight fit for sure but I didn't have to do any grinding to frame or anything.

Again, Chuck78nhas done a deep dive on the newer billetron version of the lectron carb here viewtopic.php?t=25967

Of course this is on the H series bike so a little different, but probably not enough that you couldn't make it work on an E.

Thanks for the reply and the thread! I got a response this morning and placed an order. I'm very curious to see how it performs!

[brademan76]

Oh, brademan, who / how wad the cylinder replated?

It was not replated. Ted didnt say anything about replating, but did mention getting a crosshatch back into it.

[brademan76]

]
Thanks for the reply and the thread! I got a response this morning and placed an order. I'm very curious to see how it performs!

You got the new billetron pro? Please keep us updated on your install and use.

[KDXGarage]

Is it the stock Electrofusion coating that was honed? Did he mention which kind of hone was used?

Looks like a lot of work done to all the port areas!

[SpruceItUp]

You got the new billetron pro? Please keep us updated on your install and use.

Yep! I've been wanting to test it on my other bikes, but the KDX is my priority right now, so I figured I'd grab it for my KDX. I'm wishing for good things! I'm unsure of how long it takes to deliver, but I ordered yesterday morning. Maybe within the next week?
I'll be sure to create a post on it when I go to install it!

[SpruceItUp]

You got the new billetron pro? Please keep us updated on your install and use.

Yep! I've been wanting to test it on my other bikes, but the KDX is my priority right now, so I figured I'd grab it for my KDX. I'm wishing for good things! I'm unsure of how long it takes to deliver, but I ordered this morning. Maybe within the next week?
I'll be sure to create a post on it when I go to install it!

[SpruceItUp]

You got the new billetron pro? Please keep us updated on your install and use.

Yep! I've been wanting to test it on my other bikes, but the KDX is my priority right now, so I figured I'd grab it for my KDX. I'm wishing for good things! I'm unsure of how long it takes to deliver, but I ordered this morning. Maybe within the next week?
I'll be sure to create a post on it when I go to install it!

[Chuck78]

Is it the stock Electrofusion coating that was honed? Did he mention which kind of hone was used?

Looks like a lot of work done to all the port areas!

Ted has a special diamond hone for Nikasil etc type platings, FYI

That is some fine porting work. He did my friend Sebastien's 200H cylinder and head, + Billetron Pro Series, reeds, PC Platinum 2 pipe etc, and still at 198cc with fresh plating, the bike has more power than his RMX250 with all the typical mods short of some extensive "more power everywhere" porting job that Ted Boyko gave his 200H cylinder... Ted also cut down the base surface of Sebastien's to get more low end torque, but was after a more power everywhere type porting.
The 200E cylinder and the 200H cylinder are fairly different in terms of port configuraton (I'd prefer the 200E stock vs a 200H stock, but a well ported 69mm or 70mm big bore 200H is best, and is better than even a lightly ported 220R cylinder and modded head in my opinion). The 220R has it's ports rather low already, so those don't ever really get the base milled, only the head. The transfer ports on all the above are a bit higher than desired by more current standards, but the low ports of the 220 make it so that you can't cut the base down in a lathe in order to drop the transfer ports, as the other ports will be too low then. That being said, my 220 cylinder with just some very basic porting cleanup and an RB head + 2 different Lectrons makes awesome power that gets around in the technical and mid speed woods just as well or even better than the modern 300 2-strokes I ride with. At well over 400 hours on the top end from the past 5 seasons, it's getting a bit lower on power (still does everything quite well though!), it just doesn't scare me anymore like it used to with the throttle response and massive surge of power, so it's time to retire the WIseco, or at least the Wiseco rings! KIPS packing seal replacement and KIPS cleaning, maybe send the cylinder to Ted Boyko for a honing and a bit more porting...