oko 26mm jetting

[double d 1]

just cant get it to run right. the plug is black,sooty looking. ive got main jets from 85 to 135 nothing helps. it came with a 50 pilot and i have a 38,40,42,44, i put the 44 in but still cuts out when throttle is whacked open. air screw is out 1.75 turns. i'll keep messing with it but its getting discouraging. thanks for the help.

[guy310]

Black and sooty is too rich, but I think since you've been through so many sizes, I would take the plug out and burn that stuff off of the plug with a small propane torch and start over. After the plug is clean (wire brush helps also) run it then and start from there with the color. Black is too rich. Another easy way to figure out which way to jet is to turn on the choke and see if it improves or gets worse. If it improves you jet up, if it gets worse, you jet down.

[double d 1]

as soon as i hit the choke it dies!! sounds like i need to go down some more. is the 26mm to big for a stock motor. some people here have put the vm26 mikuni on the stock engine im assuming, did anybody have any problems?

[91gtig60]

if it cuts out when you pin it real fast then lean the air screw till it responds right. i run my sons 125cc 26mm at about 1 turn. if i fatten it then when he pins it off the line it dies everytime. even on a ds90x the other day it had the same problem and it also worked.

[Ride1Rob]

I didn't have issues like that with my sons VM26. I was considering an OKO28 but read on a couple of other sites how difficult it is to dial them in.

Using the choke after a bike has been running should kill it. The choke's purpose is for cold starts. Let the bike idle for a couple and check the plug. If black it needs to come down on your pilot. If white go up. Your mid throttle is your needle position and WOT is your main. Dial your idle in 1st and move on from there.