yamaha srx250 carby problem?

[daddio]

I recently acquired a srx250 that had been sitting idle for 6 years, I cleaned and flushed the fuel tank, stripped and cleaned the carby..
From cold the only way to get the engine running is to take the side cover off and use your hand to block the carb inlet, after a couple cranks the engine starts and runs fine and restarts no problem while the engine is still warm but once its been sittiing for 20 mins or so you have to block the inlet again to get it started.
anyone got any suggestions?

[Motu]

You are choking the carb - so I'd say the choke isn't working.

[Ixion]

I presume you ARE pulling out the choke knob? And it is staying pulled out (after a while they dont stay out, you have to hold them).

[daddio]

Yes, I pulled out the choke knob and it stays out, I start the engine by manually choking the carb inlet, once the engine is running I have to push the choke back in or it runs rich, if I pull the choke while the engine is running the revs pick up so the choke seems to be working ok but not enough to start it from cold, any other ideas?

[Motu]

Low float level or not enough suck from the engine.For a quick check on the float level turn the fuel off and run dry - if it's too high the engine speed will increase before it dies,if too low it won't run for as long and dies quickly.If there is not enough suck you have valve or piston ring problems.