250es help

[Bebo]

Got my big red running with a new coil and carburetor rebuild kit it's runs good once it warms up but seems to want to cut out if I go full throttle at mid to low rpms. If I stay less than half throttle it runs fine and if I go full throttle after its gotten hallways up the rpms it's fine it's just full throttle at low rpms seems to maybe flood it? I've cleaned it and rebuilt it with a kit for the 85. Stock exhaust but it does have a cheap uni air filter.( I put I dust sleeve on it and it runs better) the bike smoke a little maybe a compression thing any advice or troubleshootings tips would be amazing!

[Flyingw]

Did you replace the brass barrel the needle passes through?

[Flyingw]

When you go from about half throttle to full throttle, the carb is going from the slide to the main jet. I too had this problem on one carb I rebuilt recently. I replaced the brass barrel and the problem went away. Remove the slide, main jet, and main jet diffuser tube. Tap the barrel out from the top with a punch or drift. Install the new one long end in first and reassemble.

[Bebo]

Sure didn't try that, but I definitely will tomorrow thanks a lot! Ill let ya know how it goes.

[Flyingw]

Also, look at the split linkage on the cable side of the carb. That split is there to be able to adjust the synchronization of the slide and butterfly valves. The idea is to have the slide and butterfly actuate at the same time from a closed throttle so you spread or narrow the slit in the slide linkage cam so it just barely touches the tab for the butterfly. I routinely have to bend the tab back down because over time, they do bend up. A good way to gage the tab orientation is to have the slit in the linkage to be even and not overly wide or pinched closed. When I adjust the slit, I use a magnifier to help me see when the linkage cam just barely touches the butterfly tab. If it is overly wide, bend the butterfly tab back down and readjust the slit.

See the Honda manual for the technical explaination on how to adjust that but thats it in a nutshell.

[Bebo]

Thanks ill have to go back over that when the carbs right in front of me. I'm still kinda new with these carbs I was gonna buy a new one but I hear the aftermarket ones are junk so I'm trying my hardest to use the factory one thanks again.

[tri again]

yupp, oem carbs can be a dream and trouble free for years when we finally get them set right.

Remember too, that the new gas has a shelf life of only a month or 2.
Nice fresh non ethanol gas may just be the ez answer.

[Bebo]

Yea after I got it running I put all new bearings all the way around ad while it was down waiting on parts I cleaned the tank petcock put new gas line and fuel filter and since then I've only ran 90 ethanol free from my local vp. People look at me silly running that in a 1985 but they just don't know what I have. Haha