First steps to get it running...cleaned the carb, changed the air filters and fuel filters and got it running for a short period. Drove it around for half an hour and it smelled like burning plastic. Took it back to my garage and shut it down and it wouldn't start again.
So then i tried replacing the ht coil which i assume was the burning plastic smell. This led it to start again and run on kickstand for half an hour. Next, i tried to dial in the carb correctly, attached a cheap tachometer and set it to what the idle the service manual said to. Then messed with the idle adjustment screw following next steps of the manual. Then moved on to the air fuel mix screw step in manual. At this point the idle went haywire revving uncontrollably fast. So i turned it off and reset it. After that it wouldn't start again for weeks.
I figure it is a little bit of a carb setting issue and possibly something else like valve clearances. This week went back to messing with it and got it to start again by opening up the air fuel mix screw slowly until it started, but idling strange still. Once it warms up it either dies or revs really high to the point of sliding the scooter on its kickstand along the ground.
Next i went to check compression but given the awkward placement of the engine shrowd, i lost the compression test spark plug hole attachment into the ether of the magneto fan. This required removing the engine from frame to take the engine cover off. So this is where I am currently at, with the engine out of frame, shrowd off and recovered that stupid brass part!
Now that engine is out and accessible, i decided to check valve clearances and replace that engine temperature sensor. Service manual says to align the marks on the cam sprocket parallel to the open case where the head cover goes on, then make sure the marks on the magneto line up with the Mark on the engine case. I've got it lined up on the cam sprocket correctly and have checked the clearances, which the inlet valve is a bit loose, and the exhaust valve is a bit tight. Unfortunately the marks on the magneto are strangely not exactly where they should be. There are 4 marks on the magneto in two groups of two. When the cam sprocket is lined up correctly, there are two marks on the magneto at 12 o clock, and two near the engine case mark around 10 o clock, but they are about half an inch above the case mark which is at about 9 o clock. Those two marks closest to the case mark have labels, one is "r" (which is the further away closest to midnight) and one that is marked "t" which is closest to the case mark. I am wondering if these can be/need to be set correctly in line with the case Mark and if so, which one goes at that mark.
Either way, for now i will adjust the valve clearances to spec.

Frame with no engine!

engine extracted!

fan cover off. Brass part rescued from the ether.

New engine temp sensor installed. Just gotta find a solution for the snap connector to the sensor cable. This replacement came bare no connector.

Who would have thought this scoot is only 4 years old, from the look of that pipe. Lived all its life outside on the streets of nyc.

cylinder head cover removed.

another view of the internals.

Cam sprockets lined up correctly for valve clearance check.

marks on the magneto.. one set of 2 at the top, one set of two around 10pm just above the case mark. the top mark on the magneto left says "r", the bottom one says "t". neither line up correctly with the case mark.
Last edited by swiss1939 on Fri, 08 Feb 2019 04:17:21 +0000; edited 2 times