Engine will only run with choke on?

[500vdue]

I started the engine from cold with choke on. Engine warmed up and as I start to close off the choke the revs start to drop and engine stops. I've wound the idle up but made no difference. Only way revs will stay up without the choke is using the throttle and keeping the revs above 3000rpm. Almost seems as if the engine isn't getting enough fuel. Plugs and air filter are fine. Anyone had this problem before?

[lygilco]

Your idle jets are blocked. Usually caused by sitting for a long time with fuel n the carbs.
Carbs have to come off - the idle jets removed and cleaned out - I use a file piece of copper (not steel) electrical wire.

[motion]

And more importantly, do you have a V-Due, and are you willing to sell it?

[chrism15]

if the idle jet is blocked you have a false air leak where the engine is drawing in to much air from places like the inlet manifold ect

if the idle jet isnt blocked then do the spray test:

remove side panels

start engine and leave it to run with as littl choke as you can

get a spray can of flammable contents - be sensible about it so use something like WD40 or Carb Cleaner DONT use things like deicer

spray over areas you think there is a air leak - inlet manifold and reedcage joints, airbox rubber, carb onto inlet manifold joint ect ect

if the revs go up or down even a little bit then its drawing in air on that joint - for example you spray on reed cage/inlet manifold and revs go up or down, the inlet manfold might not be bolted down level or lose bolts ect so it is better to remove it, clean the joint lightly wity sand paper and apply some high temp instant gasket along the joint which is resistant to fuel and oil then bolt it down tight and leave it to set

the test works as when it sucks in air where it shouldnt it sucks in some of the flammable particles and burns it where as when its just running its sucking in air and running a little lean so when you put the choke on you block of some of the air coming in making air to fuel ratio right

[cfitzpat]

And more importantly, do you have a V-Due, and are you willing to sell it?

I do, but I'm not selling it! :-) There is an ex-trofeo on Ebay currently however on auction to. No good for the road though...
Of note I had exactly the same problem on my RS and was ethanol gumming up the jets. Clean out and all much better.