Need some advice, stalled and not restarting Buddy

[dillon]

Ok heres the runs down, Buddy 50 with the Scooter Works stage 2 kit. I was running down the road at 45 indicated when the scooter lost power and stalled out. It had done this a few times on me but restarted, so I was partly riding to try to figure out the issue. This time however it did not restart.
The fuel tank is not getting a vacuum, I have great spark (pulled the plug and grounded it to the case and turned over engine, bright white arc), the carb is getting fuel (I also just pulled the carb appart to clean and inspect), engine has compression. At this point Im lost, only things I havent checked out would be the auto choke and the reed valve, however in my mind either of those wouldnt render the scoot dead, it spins over but doesnt even try to start.

[sc00ter]

What were your cylinder head temps before the bbk (did you create a data point first) and what has it been running at with the bbk. Sounds like a few to many soft seizes to me, since you said it has happened before. Did you cold and warm test the compression right after the build? If so, how does it compare now with cold readings, since it wont start for a warm reading? Pull the muffler and peek up in the cylinder and see if the piston is scrapped up from a overheat. It sounds soft seize to me so far..... Side note, did you go with carbon fiber reeds? They do break. Metal reeds cause damage, carbon fiber don't. Carbon fiber reeds are cheap insurance in a tuned 2 stroke.

[avescoots1134]

Sounds like it's time for a compression test

[PeteH]

The fuel tank is not getting a vacuum, ... the carb is getting fuel

These two statements might be contradictory. Are you certain that the manifold vacuum is hooked up correctly to provide vacuum to open the fuel valve? If for some reason that hose is compromised, you're not going to get fuel.

Still thinking fuel delivery: if you crank for a while with the electric starter then pull the spark plug, does it come out wet?

[sc00ter]

One too many soft seizes is my bet. Since you did a stage 2 kit you know how the scoot comes apart. I would pull the spark plug out to help the motor turn over faster. Put the plug cap AWAY from the plug hole. Pull the fuel line going to the carb. Stick a rag under the hose end and crank the scoot. Fuel should come out because its pulling a vacuum on the petcock. If gas comes out then put a compression gauge in the spark plug hole and crank it again to see what you get. I cant remember off the top of my head what a 2 stroke cylinder makes for compression at cold, but I bet it finally finished dying a slow death. Keep us posted on your findings. If it did lean seize, dont give up. Learn from your mistakes and try again! If its something else that caused the failure then let everyone know so the same problem will not mess up someone else.