Dynamo questions

[warmshed]

I have a DVR2 regulator for sale on the Sale and Wanted board if you require one.  Dave

[Greybeard]

That seems correct. One way to test it out, with engine not running drain the battery for a while (put the lights on), then start up and see if the meter goes into positive then slowly goes back to 0.

Yup; left the bike for half an hour with the lights on. When started the engine the ammeter moved into the positive values until the battery was recharged. 

Neil Ives UK

[Triton Thrasher]

I raise the revs the ammeter changes from showing a discharge to 0 amps; ie. no positive charge value. Am I correct in thinking that as the battery is full I should not see a positive value at the ammeter?

Neil Ives UK

If you want a second opinion, that's exactly what should happen.

[Greybeard]

Thanks TT,
I am very happy to know that my dynamo is ok.
Graybeard

[mayes]

Neil your battery will only charge when required run the battery down and recheck I am sure this is correct
John

[Dunney]

recently had cause to ask SRM how to test my dyno and they told me the following which I though was very concise.

Test the dynamo output

Disconnect the dynamo from the bike wiring Connect F and D together and connect to Negative of voltmeter Connect positive of voltmeter to earth of bike Start engine and rev up and voltmeter should easily read 6 volts through to 15v and more.

If it doesn't read anything then disconnect the F terminal and put in a wire so that the negative side of the battery can be momentarily connected - do this a couple of times.
Repeat as above.

If still nothing then -
Remove the dynamo belt
Connect F and D together
Connect this lead to the battery on the bike - as you do this the dynamo armature will turn Check the direction of rotation is the same as the direction the dynamo is driven by the belt.(motor test) If it is the same - this is correct If it is opposite then find the wires from the field coil and swap over their connections.
Repeat motor test
If direction is now correct repeat output test.

Regards
Dunney

[duTch]

 I won't get carried away,as Neil seems to be sorted, but Dunney just for the record, this was all discussed a few months ago in fair detail, and the fact that the dyno 'motors' either way is not conclusive that it's ok (I know from experience- had a dodgy armature), but simply tells whether it's wired the correct way.
  If it motors faster it may be better indication of condition than slow, but someone else will be able to verify better than I.
cheers..