Magneto remagnetizing.

General electrical problems
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Mharrisbarton
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Magneto remagnetizing.

Post by Mharrisbarton »

For some reason this subject seems to stir up a bit of controversy .ref Britbike forum. Magneto man & the man who marketed the bolt on condenser (sorry l forget his name).I have had about 6 magnetoes rebuilt in the past 20 years all of them in my non expert opinion lacking good magnetic field strength, I even once had the timerity to take one back to have it checked, he ran it for 30 minutes at 1000 rpm and he said it's fine a good consistent spark,I don't think I can kick it over that fast! this is on a bike 1938VH that I want to use regularly and I was having trouble starting it, so I raided my pigs bank and invested in a BTH transistorised unit, fitted it and it transformed the bike,I did nothing else. so my question is there anyone who can remagnetize a magneto to give the magnetic "pull "that I remember from the magnetoes of my youth. Matthew Barton.
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Roger Gwynn
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Re: Magneto remagnetizing.

Post by Roger Gwynn »

As far as I understand the subject pre-war magnets are more prone to losing their magnetism than post-war due to improvements in metallurgy, in fact it is not likely to happen to the later ones. In early magnetos a keeper should always be used when the armature is not fitted. Bright Spark are the people who do the condenser and are also the only people I know who can re-magnetise a magneto see https://brightsparkmagnetos.com/worksho ... /index.htm for an explanation
Roger Gwynn, Membership Secretary, curator of the Machine Register and the works drawings. Director of Draganfly Motorcycles, Craven Equipment and Supreme Motorcycles mostly retired.
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Re: Magneto remagnetizing.

Post by nevhunter »

I have a "professional" remagnetiser, KRYYPTON. that 2 people would have trouble lifting and find the cast in lucas magnet one of the hardest to get a good strong magnetic field into because you can't get close enough to the actual magnet itself.. IF you pull the armature out you instantly lose about 25% and if someones skimmed the armature to make it look pretty you are worse off again due to the clearance increasing. IA leaking condenser will make a starting spark weak and cause the point to burn. I have ALL the LUCAS servicing notes and go by them BUT you need an extremely Powerful magnetiser to get anywhere.. It IS possible to get an easy starting Lucas but everything has to be right.. I got the magnetiser about 40 yeas ago because I was sick of travelling miles across Melbourne twice to get a crook job done. Nev
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Re: Magneto remagnetizing.

Post by admin »

I 'stickied' the 'magnet strength' topic to be an easy-to-find reference for this topic - Matt is looking for the same info here so I'm locking this topic - please put any more contributions into the 'magnet strength' one:
viewtopic.php?t=13681

(And I've moved this from 'Suppliers' 'cos as yet no-one seems to have actually had the work done so there can't be any personal recommendations!)
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