The re-commissioning of the long stood NC35 continues, now have a running bike, fork seals done, new tyres, new chain sprockets, brakes & lines sorted and new err.........battery...... knew it was going too well.

When running (sweet as it happens) battery not getting charged from the system and reg/reg working ok (tested it on my CBR900 as its the same unit and charged at 14.5V) popped the alternator connector off and one of the 3 terminals is badly scortched/melted, as is one on the reg/rec connection.

I guess as reg/rec works this indicates that at least one of the alternator windings has burnt out and the cause of no charge to battery when running and new alternator needed ?

Electrics not my strong point and knowledge to date from other threads on this topic, but think it must be alternator.

Any advise/confirmation appreciated


https://i.imgur.com/P51hdJI.jpg


https://i.imgur.com/FPLtCoQ.jpg

Replace connectors and then measure alternator winding resistance.

As above really... youll need to replace the connections if the altenator is ok.

You can just cut them off for now and make sure you have decent wire to solder new connectors to (dont just crimp them)

If you label the 3 yellow wires as A B C get a multimeter and set it to resistance, if it has a manual scale test on the lowest setting (i.e 200)

Measure between A-B A-C and B-C

See what readings you get.. there should also be no reading between earth and any of the 3 wires.

Snipped the connector block off and all combinations read 0.8 with meter set at 200, meter takes a few seconds to settle but finally lands on 0.8 for all of them. Don't get any reading testing each wire to ground.

Think this means alternator windings are actually intact, could the melting/Charing at the connection block stop charge getting through, it was only at one of the three. Thanks

Measurement to chassis from any lead should be made on maximum resistance range. Assuming all ok, reconnect and measure battery voltage with engine running at 5000rpm. Should be greater than 14.0 volts and less than 15.5 volts.

Update - turned out alternator needed a rewind and various other electrical gremlins and previous owners botched connector repairs needed sorted. Now running perfect with alternator rewind and new lead/connector block, new reg/rec and connector block and battery now taking full charge at 14.5V running. I think the issues had gradually spread to the whole charging system over time as all relevant connectors were burnt and may even be why the bike was laid up when I bought it. At this rate it may even be on the road come spring!