opening up the choke jet

[leehuggy72]

Done the mods to my pwk 28/30 carb

drilling the 1mm hole behind the needle bush, drilling the two holes which allow more fuel into the float bowl, etc

can anyone tell me what size hole is needed for the above mentioned choke jet hole..

mine's around 2mm in size and i do have major starting problems with this carb..

30/40 kicks until she slowly comes to life from cold... soon as she's warm first kick everytime

[dapper]

Lee, never had to do anything to choke jet hole. Just the two holes you mention, the tiny one next to the main jet hole and the one through where the float valve sits. Make sure you blow through the pilot one properly with some compressed air (air duster can aerosol will do) and then shine a very bright torch through the hole while blocking the main jet with a finger. You should just be able to see light coming through it if you move the torch up and down. I think when the two halves of these carbs are put together they use some sort of glue/gasket sealant type material which can partially block the hole. I tried taking one apart, but stopped short cus the two screws were so tight I didn't want to damge the carb. Make sure your choke is working correctly. Float height set correctly (21-22mm). You may find that if you turn your petrol tap on till the float bowl is full, then turn it off. Kick her over till she starts and then turn petrol back on, she starts better. Same when stopping; rev her a little just before switching off engine, to drain the floatbowl a little.