RESOLVED: 3 weeks troubleshooting, still stuck

TURBO200R4 said:

did you spray starter fluid or propane around the base of the throttle bodies to test the base mounting yes or no?
did you unplug the connector on the map sensor to see if that would help yes or no?
did you take a vacuum pump and hook it to the map sensor and pump it to 18 inches of vacuum to see if that works yes or no?
maybe you just like working on the bike

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Valaas said:

Good vacuum readings on all 3 TB's. No leak between the head and the 4-way connector. But yes, I have sprayed starter gas both in and around the TB's.
The MAP sensor is not fed any vacuum, I have measured. Near zero vacuum in the hose feeding the MAP sensor.
And there is the problem.
That, and perhaps a problem with ignition on cylinders 2 & 3

If I didn't like working on the bike I would have replaced it with a 2020+ R3

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TURBO200R4 said:

i have been working with vacuum since 1966 and in the early 60's to 90's they used vacuum modulators on a lot of transmissions so i was constantly checking vacuum on these vehicles. i would check the vacuum canisters and a lot of vacuum hoses especially the vacuum modulators witch controls firmness and timing of the shifts. on chevys the vacuum advance can go above the throttle plate or below the throttle depending on the eternal spring and you have to know witch carb tube to put the hose on and you do that with a vacuum pump. very few mechanics knows this and that is why i consider myself and expert on this.
so what you are saying about the vacuum is impossible unless
you have cracked hoses or hoses clasping
you have a cracked tee
you have a map sensor that leak's like a bear
or you have a tee that is blocked or sealed up with epoxy from trying to fix a leak
or we just have a failure to communicate
the key word is hand held vacuum pump.

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