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Advertising and Classifieds => Douglas Motorcycles and Parts For Sale - Private => Topic started by: ANTOINE on 25 Mar 2015 at 19:40

Title: DYNAMO BTH"PANCAKE" FOR DOUGLAS AERO
Post by: ANTOINE on 25 Mar 2015 at 19:40
Hello ,
I have a 600 AERO DOUGLAS and some problems with the dynamo.There is 6 volts and more but 1 ampère only , not enough to charge the battery.
Do you know this problem ( remagnetising the magnet  ) ???. Did you know this problem ? do you know an adress to make correctly the work ?
I am in France , and I don't find a suppkier who know very well this model ?
Thank you for your help . best regards.
Title: Re: DYNAMO BTH"PANCAKE" FOR DOUGLAS AERO
Post by: summers1 on 14 Sep 2015 at 19:09
hi im ian,ive got the same problem whemn you find out what it is can you let me know,thanks
Title: Re: DYNAMO BTH"PANCAKE" FOR DOUGLAS AERO
Post by: eddie on 14 Sep 2015 at 21:37
Some of these "pancake" dynamos have a single 4 pole magnet, while others have 2 normal 2 pole magnets. The single magnet gives better output but seems more prone to problems. The usual fault is a hairline crack in the magnet resulting in 2 magnets (usually of unequal length) and an odd magnetic field that reduces the output as different coils in the armature give off opposing outputs. The easiest way to check for cracks is to pass a compass around the magnet and watch for wild swings of the needle in odd positions. A second method of checking is to place a sheet of paper on the magnet and then sprinkle iron filings over it to illustrate the magnetic fields (remember the physics lessons at school???).

  Regards,
                Eddie.