Hanging revs

[AndyD]

Hi,
Got the CJ250T back together a while ago but didn't put petrol in a couple of weeks ago when I finally got a chance to play with the engine outside.
Fired up easily but had an obvious leak on the carb manifold rubbers, ran rough and had an oil leak on the clutch side cover.
Back on the ramp.
Ordered new rubbers from Cruzinimage which arrived really quickly and fitted these.
Fixed oil leak (what a pain getting the cover on and off - involves kickstart, brake pedal and exhaust being removed / pulled aside).
Checked points and timing.
Started up much better and idles nicely but revs hang and only drop slowly so need to sort that next.
Cables are free and couldn't find any air leaks on the carb to head or filter rubbers.
I guess this means something inside the carbs needs another clean out but just wondered what else could affect this in peoples experience.
Cheers,
Andy

[Laverda Dave]

These are the symptoms I had with the Z400J Andy, hanging revs, a suspect air leak etc. Once I changed the pilot jets and gave the idle circuit another blast with carb cleaner all the problems disappeared. Got to say my old Gunsons carb tune kit worked wonders for the first time ever. Even after replacing the pilots it was still a bit hesitant but once I fine tuned the mixture and a quick sync of the carbs the world became a better place and I celebrated with a bottle of Tim Taylor's Landlord 🍺.