A 'charging' question.

[Pharisee]

I noticed whilst riding my newly acquired M18S that the ammeter wasn't showing a charge when the engine was running but it showed a discharge with the lights on (and the engine running). I guessed that there was a problem somewhere... I'm quite bright like that (unlike my 6v lights)
The wiring was a bit of a mess around the battery with rubbish crimp terminals and lots of insulation tape so I sorted all that out with new wires and 'proper' crimped bullet connectors. Fired it up and there was still no charge... however, when I stopped the engine, the ammeter needle, which had been sitting in the centre doing nothing, swung over to discharge. I'd got no lights on so I disconnected the battery.... ammeter back to centre. Connected the battery again and the ammeter stayed in the middle.
Started the engine again and this time the ammeter showed a half scale charge... but again swung over to full scale discharge when I killed the engine. I disconnected the battery gain and the ammeter went back to centre and stayed there when I reconnected the battery.

This bike has the old mechanical regulator box and it's been at least 45 years since I last owned a bike with one of those. I suspect the regulator may not be working correctly so at the risk of being hung, drawn and quartered by the rivet counters, I'm considering replacing the old regulator with a modern solid state item like the DVR2 shown here : http://www.dynamoregulators.com/dvr2.php

Has anyone had any experience of them?

[Rob Harknett]

Sounds like a CVC problem, ( sticking open? ) perhaps also a polarity check needed..... check all connections are good, bit of cleaner sprayed on the CVC etc. What you could call a bit of TLC after a bike has been standing is all that's needed.
Its these problems that could kill a solid state unit before you even get to use it.

[ajscomboman]

DVR2 is the way to go without a shadow of a doubt.

[G15 Roy]

I always carry one in my pocket just incase.

[Groily]

It is the way to go imho too.
Sounds like the cut-out is sticking shut when it should open to disconnect the battery from the dynamo (the reason for the massive discharge with engine stopped - which is a fire risk if not dealt with by disconnecting the battery pdq.) Also sounds as if your mechanical box has other faults. Might just be dirt and stuff, but might also be a loser's game to persevere with it and have constant worries.
The cut-out/regulator problem you have wouldn't kill a good solid state unit - a solid state one wouldn't let it happen in the first place! It's one of the reasons why some of them, DVR2s particularly, are so worthwhile.

[Rob Harknett]

OF cause the CVC wont kill the new solid state unit, as that will be replaced by the new solid state unit. The mess of wires? wrong polarity ? solid state CVC will not cure that, but it may kill your new solid state unit.

[Pharisee]

OF cause the CVC wont kill the new solid state unit, as that will be replaced by the new solid state unit. The mess of wires? wrong polarity ? solid state CVC will not cure that, but it may kill your new solid state unit.

Thanks for your comments, Rob... I will take note of them. There was no 'wrong polarity' if by that you mean the battery connected the wrong way round. It's definitely wired positive ground. As far as I can tell, the wiring is correct in as much as all the wires go to the correct places, it just that some of the connections and some of the components aren't very good. I'll almost certainly create a new loom and rewire the bike completely... it really is so simple on these old machines. Dynamo, battery and lights... that's about it. I've rewired vehicles an awful lot more complicated than that I will, of course, include a fuse and run a positive return wire and not rely on frame connections back to the battery.
As the general consensus seems to be in favour of the DVR2 regulator, one is now on my shopping list. The old girl is basically sound, she just needs a little TLC.

John

[Rob Harknett]

I switch to solid state CVC many years ago on a bike I used regularly, also switch to Cyclon battery's. Everything was fine for many years, that includes the same battery's. Then that particular bike never got used for a while. It stood un used. Earth points failed, connectors oxidised. Solid state unit seemed to be dead. I put back the old CVC unit. Went through all the wiring, sorted out the dynamo, that was going the wrong way, but easy to flash with the old CVC. Only when the wiring etc was all OK again did I refit a new solid state CVC. So the point I was trying to make was, get the bike sorted before fitting a solid state CVC. Years later I have the same problem again. Dynamo won't work, bad earths etc. I thought I had done enough to fit a new battery and give it a try>>>>> I was called away after I fitted the battery. When I got back to the bike the battery was flat??? Should had been dry charged when I got it. Charged it up, still no good, then I noticed a live wire on the dynamo. Yep solid state unit failed. But not before the dynamo burn out.

Rob what exactly is the DVR2 you find good. I have been using the very first early type of solid state CVC. The type the late Neil Lynne sold, 20 odd years ago. I guess they are much improved now. I need to rewire some bikes. Most were rewired in the mid/late 1980's. The only bike that still seems to be OK is a 1936 AJS. That has 3 brush dynamo. ( no CVC )

[aobp11]

Why would you give up so quickly John? I would be curious enough to remove the dual seat and to see how the MCR2 is acting mechanically when the engine is running.
You didn't tell if you also checked for charge/discharge with lights on during the second attempt.
Maybe you installed a new and fully charged battery? That could make the difference between yes/no cut-out when the engine is stalled and could explain why perhaps the previous owner had no problem. You might screw in the corresponding adjustment screw a little bit and try again.
It's also normal then that the ammeter initially (several minutes during normal driving) shows some discharge when the lights are switched on.
The charge current for a modern, already fully charged AGM battery should be very small, hardly visible on your ammeter (so even with lights off). Maybe the previous owner set the regulator adjustment with this in mind. It's not strange that the ammeter showed (considerable) charge during the second attempt, since the battery had to deliver that very large current during some time. But the charge current should reduce to near zero within in a few minutes.

Albert

[ajscomboman]

Rob, there are several advantages with a DVR2, they regulate the current more steadily and have the ability to be swapped between 6V and 12V with out cutting any internal links like the V Reg also it's ability to still kick in with a flat battery if the need arises. The early V-reg that you refer to does not have that capability neither does the V-reg2 I'm led to believe. The DVR2 also fits into an original CVC case more easily as well coupled with the fact that it also doesn't require to be mounted in the air stream just make them more appealing. I have a V Reg2 which I'm happy with but over the last few yrs have swapped over after purchasing the first DVR2 because of their superior ability.