The BSA A7-A10 Forum

Technical (topic titles must be descriptive) => Lucas, Ignition, Charging, Electrical => Topic started by: rockthedog on 10.02. 2012 21:29

Title: magneto
Post by: rockthedog on 10.02. 2012 21:29
hi all got manual advance retard on my 58 a10,  got a new old stock mag for a very cheep price of £50.00 can i just change the cog to auto advance unit in timimg case, cheers mal. *smile*
Title: Re: magneto
Post by: beezermacc on 10.02. 2012 22:03
Yes!  If I understand correctly you are planning on putting a magneto with a fixed cam ring and auto advance, in place of your manual A/R magneto. Of course you will lose the manual A/R facility. If you have to use the manual A/R when riding, maybe because the bike pinks under load, you will have lost the ability to overcome this. If you never use the manual A/R, other than for starting, you may not notice the difference.
Title: Re: magneto
Post by: Triton Thrasher on 11.02. 2012 09:31
You can keep the manual facility working, after fitting the auto advance.
Title: Re: magneto
Post by: trevinoz on 11.02. 2012 22:14
Yes, but why?

  Trev.
Title: Re: magneto
Post by: a10gf on 11.02. 2012 23:42
rockthedog wrote:
Quote
got a new old stock mag for a very cheep price of £50.00
*smile* that's a great deal (envy, envy... *sad2* )
Title: Re: magneto
Post by: Triton Thrasher on 12.02. 2012 01:06
Yes, but why?

  Trev.

Because it's already there.
Title: Re: magneto
Post by: beezermacc on 12.02. 2012 19:20
The benefit of fitting both auto and manual A/R is that the ATD automatically retards the timing on start-up without weakening the spark (the manual A/R weakens the spark when you retard the lever), but you can still use your manual setup to deal with pinking under load. I didn't mention this in my reply because rockthedog doesn't have the option of both unless he starts mixing and matching bits, which is not recommended!