6v to 12v conversion

[Triton Thrasher]

Good stuff Trev. Maybe some conversions aren't as good as yours.  Years ago, a guy on the phone at SRM was very reluctant to sell me a 12V dynamo, even though they had them advertised, because they weren't lasting long. I know that's hardly first hand experience.

I did many miles with a 6V dynamo at 12V. Probably lightly loaded most of the time, but did have 60W headlight and coil ignition for a while.

[BSA500]

Hi,
I had my dynamo sorted by Andy at Priory Magneto's. Because I ride all year round in town and country he recommended the 12 volt wound. Before that the battery would flatten and the dynamo would overheat,so much so last time the armature expanded and split the bearing .
So now I run DVR2,12 wound dynamo and a 9ah lead acid(used the gel cells but they didn't like the flat/charged cycles so much ).Andy also recommended I go back to chain drive as he feels the tightness the belts run at can be a little harsh on the dyno bearings. Not aproblem as the dynamo now cuts in at BSA designed speeds.

[metalflake11]

Well you live and learn something new every day!....Thanks Warmshed.

[bikemadinspain]

Thanks to everybody who gave the great info on this post and especially to the chap who asked. I have been wondering about how the hell I was going to sort this problem for a while and now I have a better idea, cheers.

PS; Me and electrics, we get on like me and my first wife!!!!

[BSA500]

Update... A year on and no issues bright lights all the time incl all last winter(except when it snowed) 

[terryk]

One thing I always do when wiring up a bike is run an earth wire from the headlight to the battery earth or frame earth. This is instead of trying to get a good earth thru the grease in the fork triple tree bearings. It does make a difference to the headlight brightness.

I've always just used 6V it's ok for me. If I had to get a dynamo completely overhauled I would probably go to 12V if I didnt have spare good 6V dynamos which I do have plenty of. I've just always kept the old 6V ones working.

A good battery is the key I think if its going flat easily ditch it and get a new one. If I ever get a flat battery for whatever reason I pull it out and charge it with a charger instead of trying to let the dyno on the bike charge it. Its just what I do but if its night time and you need to get home do whatever.

Rant over

[Greybeard]

One thing I always do when wiring up a bike is run an earth wire from the headlight to the battery earth or frame earth. This is instead of trying to get a good earth thru the grease in the fork triple tree bearings. It does make a difference to the headlight brightness.

I bought a new loom for my A10, (from Draganfly I think). I was pleased to see it included earth return wires so the frame is not part of the electrical circuits on my bike. The 6v lights seem pretty good to me, however  I know that headlight strength requirement is related to speed; I tend to ride at a suitable speed for the machines brakes and lights.

[1959superocket]

Hello,
My bike has E3L 60 watt dynamo, SRM dynamo belt drive, DVL2 voltage regulator and 2 cyclon dry cell batteries in series.

The dynamo was restored to 6v standard for the thicker wire rather than the thinner wire for reasons stated by others and the regulator steps it up to 12volts.

The bike has SRM electronic ignition in the K2F magneto and I think this takes just 9 of the 60watts and the only other pull in daytime is for brake light so I have some charge going back into battery.

You need to add up all the wattages and even with the faster spinning dynamo if you up the ratio I think you might find the E3L will struggle.

You could use Paul Goffs low wattage LED lamps instead of the normal headlight tail and stoplight bulbs but if it was me I would look to use one of those replacement alternators rather than the E3L.
Regards
Stuart


 

[fido]

You might need some of this:

[muskrat]

Looks like you have used it all fido.
Cheers

[bsa-bill]

Some nice shots on your page Fido - got a good eye methinks