The BSA A7-A10 Forum

Technical => Lucas, Electrical, Ignition => Topic started by: RoyC on 23.03. 2018 07:44

Title: dynamo temp
Post by: RoyC on 23.03. 2018 07:44
Does the dynamo get hot ?
Thinking of smartening mine up a bit.
Title: Re: dynamo temp
Post by: morris on 23.03. 2018 09:22
If you mean painting, it can be done but the paint isolates the dynamo body from the engine. You’d have to run a separate earth wire from the dynamo to engine or frame
Title: Re: dynamo temp
Post by: bsa-bill on 23.03. 2018 09:46
does the dynamo body need to be earthed ?, it is a two wire system and can be polarised either way by simple flashing, I'm thinking it would prevent polarisation if it were necessary to be earthed
Title: Re: dynamo temp
Post by: RoyC on 23.03. 2018 09:57
If you mean painting
Not painting.
I was considering covering the top/visible part with either aluminium tape or a shaped piece of stainless steel.
The main body of the dynamo would still be in contact with the engine.
Title: Re: dynamo temp
Post by: duTch on 23.03. 2018 10:03
 
Quote
does the dynamo body need to be earthed ?, it is a two wire system and can be polarised either way by simple flashing, I'm thinking it would prevent polarisation if it were necessary to be earthed

 A bit off-topic but; My limited understanding is that YES- it needs to be earthed, which the body *normally* does. The green wire feeds the field coil, and the yellow wire uploads the hefty (up to)~10amps *whistle* to the regulator...I've run a earth wire to battery from the common field/brush wires terminate on the bearing boss in the body, I do this because my (dynamo) body is a bit crusty so don't fully trust it ...

 To answer the question
Quote
Does the dynamo get hot ?
......dunno, I guess so- depending on the ambient air temp, the demand on the unit, and the transferred heat from however hard you ride the motor. Maybe buy a small oven thermometer and stick it in there and let us know, everywhere will be different.

 You posted while I was writing;
Quote
I was considering covering the top/visible part with either aluminium tape or a shaped piece of stainless steel.

 I'd say the more free air they have the better

Title: Re: dynamo temp
Post by: Triton Thrasher on 23.03. 2018 10:06
The dynamo body must have electrical continuity to the battery earth terminal.

Dynamos can overheat.



Title: Re: dynamo temp
Post by: Greybeard on 23.03. 2018 10:14
Andrew at Priory magnetos, (https://sites.google.com/site/priorymagnetos/home)  may be able to provide you with a plated, (not chrome) dynamo body; he did for me.
Title: Re: dynamo temp
Post by: RoyC on 23.03. 2018 13:07
Andrew at Priory magnetos, (https://sites.google.com/site/priorymagnetos/home)  may be able to provide you with a plated, (not chrome) dynamo body; he did for me.
Is Andrew trading again then ?
Title: Re: dynamo temp
Post by: Greybeard on 23.03. 2018 13:26
Andrew at Priory magnetos, (https://sites.google.com/site/priorymagnetos/home)  may be able to provide you with a plated, (not chrome) dynamo body; he did for me.
Is Andrew trading again then ?

From his website:
Business Hours:   Mondays and Tuesdays only, 9.00 a.m. - 4.00 p.m. Business hours telephone no. 01625 265185.
Please don't telephone outside business hours but you can e-mail spares requests...