KDXRIDER.NET

I know RB designs no longer sells or mods parts. How is the fredette head mod? Im going to install a ported cylinder on my 99Kx125 e series hybrid. Thinking of sending the head out unless someone has an e series rb head laying around or a carb. I could use a carb boot as I've got a boyeson rad valve but picked up a vforce 3 but didnt come with one. I have a spare cylinder but would need to be sleeved or seriously repaired I could trade. Plus the rest of the engine that came with the cylinder. Idk I thought I'd put it out there

from what has been discussed here the E series head is already pretty good compared to and H series head, squish band is much wider, produces more low end power, etc. Chuck78 can fill you in with a more long-winded reply.
I sent my E series head and cylinder to Ted Boyko in Southern CA and he removed a little material from cylinder base slightly milled the hea, in addition to some port work. Very noticeable low and mid power improvement.

some previous discussion: viewtopic.php?t=26022&start=20
viewtopic.php?p=230368#p230368

Thanks for the reply. Im really looking for more top end power then bottom end. I've got an H series pro circuit platinum pipe and shorty silencer fromm a kx 250 and Jaguars cdi box paired with a 08 crf450r coil. Same spacing as the kdx. Im kinda wanting it to have more top end then bottom end. The cdi box definitely helped. It gave it a noticeable bottom end gain as well as over rev and midrange. It's funny after I installed it I held the kill switch down for the normal amount of time and when I let of instead of the engine shutting down it lit back up. Maybe I'll just leave it be. I've searched ebay for heads that looked like they had work done to them and carbs with divider plates but no avail. Thought I would see if anyone here wanted to part with any.

I had RB do a head mod for me less than a year ago. I'd contact them. I found a clean, stock head on Ebay.

I asked him recently he said no. I just put my top end together. Bought an IMD piston. Cast piston. I have a sleeve and went with .25mm over. Just buttoning up the engine today. I doubt I'll find an Rb head. Maybe ill send one to Fredette. Check out the IMD piston. Cast. Made in Japan. Slightly higher dome then the wiseco and has 4 holes drilled on the exhaust side to help cooling. Hopefully this new cylinder and piston give me the power I was looking for

interesting on the imd piston. thanks for sharing!