1986 pro v 150 j Electrical tachometer issue

[Dltbr531]

I have a 1986 Yamaha prov v 150 been sneezing at low rpm with a drop off in power recently. The tachometer was jumpy and would run up to 5k under load with a top speed of 40 mph per gps ran (62 at 6k last year)which also is showing 12.2 volt wot which drops to 10v when using the tilt trim switch.

My actions so far was compression test with 103- 105 on all cyls new boysen power reeds , fuel lines from tank to carbs , new fuel pumps , carb rebuilds a CDI stator and new Yamaha 703 throttle control and cable. (Needed new shift and throttle cables cables so put the entire assembly on with new 10 pin cable ignition switch and tilt trim switch. and new spark plugs with each coil wire clipped and grounds all cleaned with each plug checked for spark which is yellowish not dark blue on all 6 plugs

After all that the tach at idle says 4K and goes to 7 k wot with max speed of 49 mph runs and idles fine but voltage is still a max of 12.6 at wot and drops to 10-11 when using tilt trim switch I disconnected tach and same performance.

Any suggestions from anyone would be appreciated on what appears to be low voltage creating a weak spark and the tach being wrong.

Thanks

[rodbolt17]

time to test the charging system.
but that system did not have much output to start with.
that system does use the stator lighting coil for a tach signal.
the voltage drop when using the trim is rather normal.

[Dltbr531]

Thanks

Will be testing the stator again , when I installed the new stator it tested good as well as the voltage regulator also tested good. Will pull it apart again and get the magnifing glass out on every wire and retest everything again .

Thanks again