Triggering the relay with the switch wire clicked the relay and provided 12v to the fan connector. Once I hooked up the fan and measured across the power and ground wires at the fan, that voltage dropped to .45v.
The problem was corroded contacts in the relay. Showed good without a load, but once the load (fan) was applied, the corroded contacts couldn't pass enough current.
Opened up the relay and cleaned up the contacts and all is well.
Out of curiosity, were the contacts in the relay bare copper or silver plated?
Also hoping you're not piercing the wiring insulation with your meter probes and setting yourself up for trouble down the road. I've repaired enough taillight harnesses over the years due to harnesses being probed and leaving tiny holes in the insulation and allowing moisture to enter the wires and corrode the copper wiring. Up here in Canada, especially in Ontario, they put salt on the road to melt the ice (and white wash our vehicles). Talk about corrosion !!
K.I.S.S. principal- keep it simple stupid. Preached it every day at the Nuclear Power Plant. Overthinking problems caused me more grief as a supervisor...
propav8r wrote: The relay had silver/gray contacts. Almost like tin or something.
It's a silver plating. Highly conductive reasonably high melting point. We used to rebuild relay contacts at the Nuke plant. I had my welder build up the copper contacts with Sil-Fos which is a silver brazing rod and then dress with a file then 2000 wet/dry paper.
Sorry for the slowdown in updates, I've been travelling for work. Before I head back to Florida tomorrow, I figured I'd slap the carbs back on and see if I could get it fired up. After a bit of chugging to fill the various circuits of the carbs, it jumped to life.
Revs perfectly and cleanly now thanks to Scotch's adjustment method. Starts easier on the choke too after synchronizing the choke lifters too.
I've got an airbox and boots on the way from the UK now. Can't wait to get those on and get the bike to where it can really be ridden.