300 watt dynamo/alternator on my Square 4!!

[Fredbroadbent]

Well, I finally did it!!! I have a 300 watt dynamo on my MK11 Square 4. I have had the bike since 1969 and can now ride it without worrying about as to whether the charging system will get me home!

I have a modern Japanese 300 watt alternator fitted inside a stainless steel but similar looking, but not a double of the original 70 watt Lucas dynamo. With a turned on, larger 50 watt headlight squeezed inside the headlamp cowl, it charges at less than 30 mph in top gear. Very impressive. No regulator or rectifier needed, it's all internal. It doesn't come cheap but heck it was the best thing I have done to the bike alongside the Morgo oil pump. I will post this in the electrical section also.

Cheers .. Fred
Fredbroadbent Online

[john.nash]

how expensive is ... "It doesn't come cheap " .... ?

[Fredbroadbent]

In UK pounds it costs 540. If you provide some doner parts it can be down to 450.

Fred

[john.nash]

*choke*

dat's alot ...

[Fredbroadbent]

Yes, but then cost a new generator, rectifier/regulator/relay for a modern bike and it makes the 540 sound like a bargain and it is a tremendous improvement and reliable.

[david.anderson]

I would have to agree that it is the ideal upgrade and the best upgrade that I have done to my 4. To a casual observer the bike looks original. As many of the older Lucas generators need rewinding and the regulators are on their last legs, the extra cost of the alternator is not so much. I am running the same alternator a 60W headlight, TFI electronic ignition, handlebar heaters and a seat warmer and the ammeter still balances at 30mph in top. It makes riding the bike that much more enjoyable.
That said there have been a few problems with the gpz Kawasaki alternator (not in our Ariels) that are known in the industry. The problems have mostly been with age related bad electrical connections causing overcharging but there have also been some issues with the internal voltage regulator. If anyone experiences any charging problems the first place to look is the harness connectors. This link gives advice and new regulators can be purchased there.
http://www.electrosport.com/technical-r ... ?model=397
David

[nevhunter]

Bit of a hard decision. I guess if you ride a lot and end up in rain or fog or at night you have to get more reliable electrics. I jkave kept any bike I own on the originals so far but the lucas magdynamo is far from perfect. The maggy part I don't get a lot of problem with and that is the part that makes it run. I have been riding Brit bike since I first got a licence and there was always the possibility of the light going out when riding. The dip switch was suss. the don't call Jo Lucas the "Prince of Darkness for nothing. The regulator is a pieced of trick stuff but if some old codger can set one up coreectly they do work especially the later ones with the resistor in them. Airgaps and spring tensions must be right as well as the points. I CAN understand substituting something different especially if it works well. IF it doesn't where are you then? You would need some service back-up to rely on.. Nev

[john.bebb]

Hi Fred; - please - was the alternator from Bennet Longman of Iron Horse Spares? - I wish to fit one to my ' 49 Mk1 but I've tried to contact Bennet at Iron Horse Spares for nearly a month now and have had no reply... please where did you source the alternator? Thank you. John.

[Fredbroadbent]

Yes. Iron Horse Spares is correct. Keep trying. Have you emailed or called them?

Fred

[john.bebb]

Hi Fred - thanks for getting back... I've been emailing and 'phoning I.H.S. for the past month and as yet no response...
I'll persevere. John