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BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: Captain Mike on 06 Mar, 2021, 14:27

Title: Contact breaker adjustment nut sizes
Post by: Captain Mike on 06 Mar, 2021, 14:27
Hi All
Can somebody tell me the size of the nut on the contact breaker for adjustment, cant get anything in there except the correct wrench/ spanner but I don't seem to have anything that will fit and can't find any info or spanner on the usual web sites

1957 G/F plunger


Thanks
Mike
Title: Re: Contact breaker adjustment nut sizes
Post by: Ian C on 06 Mar, 2021, 15:24
Not sure of size, but you may need a set of magneto spanners (for BA nuts I believe).
Title: Re: Contact breaker adjustment nut sizes
Post by: JulianS on 06 Mar, 2021, 15:46
The  nuts are 4BA (and threads are 3BA). Not much space in there.
Title: Re: Contact breaker adjustment nut sizes
Post by: idie on 06 Mar, 2021, 17:45
I find that a 7mm spanner will fit.
Title: Re: Contact breaker adjustment nut sizes
Post by: Captain Mike on 07 Mar, 2021, 09:18
 Hi All thanks for your help

I will look for some magneto spanners, I tried  7 mm spanner but it was too big and the 6 mm too small
Any Ideas where to get the Magneto spanner set ?

Thanks

Mike
Title: Re: Contact breaker adjustment nut sizes
Post by: bikerbob on 07 Mar, 2021, 10:16
You can pick them up from ebay put this number into ebay and it will show you a set for £6 133653421964
Title: Re: Contact breaker adjustment nut sizes
Post by: idie on 07 Mar, 2021, 10:25
That's the problem. With metrication the hexagons are most likely metric on replacement points.
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