mrkprsn - I think the voltage came up as a result of a combination of disconnecting the (OEM) ground in the stator, using the Electrex World reg/rec, and running with a battery (a.k.a. capacitor) which is required for that reg/rec. I’m not sure that I previously had all three in place at the same time during testing or riding. I’m still not convinced all is right, but I’ve never measured that much voltage before so moving in the right direction.
Nigel - thanks for the idea. I’ll test it out depending on how the voltage looks going forward.
Nick - my bike seems to be putting out the right amount of amps from the generator so I think the flywheel magnetism is okay!?! Would love to check it though. Unfortunately a lot of the tools and knowledge is disappearing
Max - I won’t rule out an overfilled battery
if it stops leaking before running low on liquid then I will know. Thanks all. I’ll update more as it comes. Once this is confirmed sorted I’ll try to make a summary post to save everyone from reading this whole thread!