ignore this if i'm off the planet [old age] but at work back in the day we had a G or an H [RH side mag] & had only one of the two coils rewound. think one is cdi charge & other is high speed incorporating trigger. Anyhoo--ran like crap but more importantly i think it was retarding off severely. The rewinder guy said reverse the wires on 'that' coil which fixed it. Talking a lifetime ago but some of this might be relevant. One other thing & might've been my F--they had a looped black wire coming just out of the box then back in which we were told to snip & isolate to let it advance more, [might be relevant to the G as well]. Best way for you to prove any of the above is to put a couple of twink marks close to TDC on rotor & stator--not necessarily accurate but just witness marks to get a baring [spelling] & then strobe to see what it's doing in relation to advance/retard. Just thinking about it--if you put the marks right at TDC as you feel it rocking over the top, or nail down plug hole trick, then strobe to see if it's a reasonable distance advanced & how close to tdc it retards off at high revs. Woffling sorry. Have a good day. Had mine on Alky [methanol] was 'purple shell racing special' back in 1980 & was a rocket, then i got a 465G & my arms are still stretched lol.