Gave my rocket 3 carbs a good clen --ultrasonic and probes all sprayed out clean and sure enough starts 1,2 kick runs for maybe 1/2 mins and then stalls as I am sorting the tickover . which is the best way to sort float height accurately ,I did see an elaborate way back a while with lots of tubes etc could it be the bowls are not filling enough , am I correct in assuming the float height should be 2mm below gasket --I have the new adjustable floats --thanks for any help.
Quote from: thunderboltandlightfoot on 07 Aug, 2025, 22:33 Gave my rocket 3 carbs a good clen --ultrasonic and probes all sprayed out clean and sure enough starts 1,2 kick runs for maybe 1/2 mins and then stalls as I am sorting the tickover . which is the best way to sort float height accurately ,I did see an elaborate way back a while with lots of tubes etc could it be the bowls are not filling enough , am I correct in assuming the float height should be 2mm below gasket --I have the new adjustable floats --thanks for any help.
Have you run a drill through the pilot jets as this is a typical cause for the symptom you describe (assuming your tank filters are clean, taps not sludged up etc).
Correct size for a number 25 pilot jet is #78 or 0.017" diameter.
For some reason ultrasonic cleaners don't get in there to remove the scale from the jet.
Technique involves the tiny drill and Aralditing it into the end of (eg)a red WD40 spray tube. Then removing the pilot screw and running the drill through on axis and lined up. Then blow out with carb cleaner. Early carbs have the removable pilot jet so easier to clean.
Please post back once you've tried this.
Are your Concentrics the ones with the removable pilot jet or the one pressed in behind the idle screw?
On my Road Rocket fitted with a concentric i had the same problem and no amount of cleaning would shift the very hard deposit in the idle passageway. I had to drill the pressed in jet out and use wire to move the crud, then tap the body and fit a removable jet. Everything looked clean but there was no flow through the idle circuit.