Ariel Owners Motorcycle Club

Hello, The problem I have is on start up the dynamo (c35sd) on my 51 sq4 doesn't seem do do anything until after about a minute of running it comes to life, I have to rev the engine and sometimes switch the lights on and off to get a + reading on the ammeter. I overhauled the dynamo during the rebuild. I have a new battery fitted and use a DVR2 regulator. After the dynamo kicks in it charges ok, but I have to go through the same sequence on initial start up. I'm thinking the field coils are weak.

hi have you made sure the dynamo has got a good earth and all the earths on the bike and the regulator can some times be a bit lazy to start up

Thanks for reply, I will check earths but I think they are good.

hi Brian have you check the volts at the battery with the engine running, my 6v is showing 7.2 volts with the engine running but no Amps till i rev it or ride it then it shows it charging i put it down to the new type of regulators

Will check tomorrow, the bike runs a bit rough until it starts charging, then its fine.

My magdyno dynamos do this.
The electronic regulators, fitted inside the original reg boxes, seem to want a bit of current (generated by revving ) to wake up.

The reason I posted was because I don't like revving the engine from cold. Its made feel a bit better knowing that its a ''problem'' with the regulator and not the dynamo probably.

You can run a wire from the Dynamo wire to the Field wire with a momentary switch in the circuit. Touching the switch should be enough to wake up the regulator. A bit of a bodge but what the H***

The problem is a function of the internal resistance of the electronic
regulator. Chris's fix works by by-passing the regulator momentarily.

Heres what the makers hd to say