Scooter update- its broke

But only for a little while. It has been sitting for 10 days or so now while I finished up last term and some of the critical yard work and shop cleanup. When I parked it, it was running terribly, not idling but running at nearly clutch engagement speed with the throttle closed. And something was vibrating pretty badly and the sound was leading me to guess perhaps the exhaust pipe was loosening.

So last night, after dinner, kitchen cleanup, yard mowing and fixing the water system, I finally got around to looking at the scooter. Sure enough, one of the exhaust retaining nuts has disappeared, causing a leak. It didn't appear to be the source of the noise from the vibration that I had been hearing. That vibration turned out to be a very loose intake manifold, which explains the high engine speed due to the vacuum leak and the lean condition it created. Strangely, I had only recently installed that intake manifold and because I knew the flange threads in the head were getting worn, I must have not torqued things down securely.

Today I took the cylinder head to the machine shop for heli-coils for new threads. I'll need to buy some new nuts and lock washers for the exhaust side and I hope I can return to studs to hold the intake manifold instead of bolts when I put things back together. I'm making a 3/16" spacer to raise my intake manifold so that the carburetor clears the motor mount just a bit better. Once that's all built, I should be able to remove the carb without removing the manifold and everything should last longer.

On the way home, I'll go to the Wood Hobby Shop to use their table sander on my adapter and pick up my cylinder head. With luck, I'll have everything back together tonight. After spending $71 to fill up my truck today at lunchtime, I'm really ready for some scooter commuting and letting the truck sit!