1wg carb advice please....

[RussellJupp]

Hi all,
Have a minor, but irritating fuelling issue.
Bike was stood for 9 months before I got it, and carbs were full of jelly, jets mostly blocked or crumbling....
Anyway, just had all 4 carbs stripped and ultrasonic cleaned, new jets where needed. Balanced with vacuum gauges.
Engine will now idle perfectly, and will rev cleanly. However there's a horrible flat spot just after idle, resulting in the engine trying to die. Airscrews are set to 3 turns open.
Any advice welcome!!
Cheers,
Russ

[Evilchicken0]

3 Turns sounds different to standard ... you could have a look in the setup manual in the Document Library (the links at the top of the page) remember that's for a 3TJ SP though

[laminator]

Is your EXUP valve working correctly. Try disconnecting the cable, at the servo end, and pull the cables so the valve is in the open position. Just to see if it makes a difference.

[RussellJupp]

Sorry, should have said it is a non exup...
Also has a micron can, and 85 size main jets.
Ta
Russ

[willandrip]

3.5 turns out.
Taken from the American 3BF model manual which is about the nearest cross reference for a Genesis.

What end can ?
The original pipe is a bit restrictive and the carbs are tuned to suit.
If an open can has been fitted; try to rig up some sort of restriction to the outlet and see if the back pressure helps the
motor breath at low rpm.
This is exactly what the Exup does on the later models..

[RussellJupp]

Ok, airscrews now at 3.5 turns open. Idle is better than before, but flat spot still there. Its an open micron can, not loud, but it does spit flames occasionally on the overrun!! Will use something to partially restrict the outlet, and see if there's any difference. Ta, Russ