Alternator overcharging problems, oil-cooled engines

Alternator overcharging problems.

Right then ive got to the bottom of this problem and i bet most oil coolers have got this problem thanks to stuart who is a very clever electrical engineer/design.

Suzuki have tried to be clever using a closed loop design which may work when everthing is new perhaps.

Out of alternator are two leads the main power to battery and the other is the ignition feed to alternator which is trigger to turn reg on.
Problem here is voltage drop on the trigger wire, ive measured half volt purely at ignition switch, suppose age takes its toll. ive got further .3 volt loss through wiring and joints i can tell you the connectors are clean and look good.
So alternator battery lead reads say 12.6 volts (engine off) ignition lead reads 12.5 volts but lights on this drops to 11.5 volts where the battery lead reads 12.3 a drop of .8 through switch and harness, so when running when lights are turned on alternator compensator by ramping up output to 15.4 volts which cooks the battery.

Remove ignition feed wire to the alernator and use it to power a relay (switch side) the ignition wire out of alternator straight to positive on battery via the new relay.
Result constant 14.3 volts depending on battery state no matter whats on or off, result.

You have to connect via a relay as the reg would drain the battery in no time as this is trigger to turn reg side of circuit on as its a basic deign not like car 1 wire systems where the actual rotation of alternator triggers it on.

In the past ive destoyed batteries for no reason luckily the powerful little gel battery has lasted 3 years but at least now know the reason why, this has got to affect a lot of bikes this sort of age pointing bto reg when actually its working correctly.
Hope this is of i must also do a right up on cvs and good design change, to stop emulsion tubes wearing out.

Ignition wire from alternator ( to work out which of two wire this is it will be the wire that only has 12 volts on it when ignition is turned on, ie black wire on multi meter to earth red on meter prod each of cables in back of plug)

Cut this wire, the one coming from alternator now connect to positive on battery via a relay.
The other side of cut ignition wire coming out of loom connects to the switch side of this new relay obviously the other side of switch side goes to earth.
So when ignition is off relay is open so connection of battery to ignition wire on alternator and visa versa.

Just one thing: first i tried with a cheap relay, it had a difference of 0,2V on the switched wires, so it charged 14,7V. Then I got a better relay (no difference measurable) and it charges perfectly.

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