Static Timing - Boyer

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
Locked
User avatar
Martin.S
Posts: 443
Joined: Sun Mar 18, 2018 12:02 pm
Location: Bristol UK

Static Timing - Boyer

Post by Martin.S »

I have a few Boyer kits left over from my T140 days and so I am going to use one of these on my G5 by making up my own 3"back plate.
I've raised the compression of the engine to somewhere around 9:1 so was thinking of using the latest G2 CSR figures for the timing - 27 degrees BTDC fully advanced.
Timing up the Boyer has to be done initially static by lining up the hole in the stator plate with one of the magnets on the rotor.
So my quandary is where to put this static timing hole in the stator that I'm making? The Boyer site says the advance in the ignition box is 15 degrees at 2500 rpm-so do I just add this to the 27 degrees fully advanced of the CSR figure and set this hole at 42 degrees BTDC?
Cheers
User avatar
dave16mct
Member
Posts: 3234
Joined: Mon Jan 01, 1990 12:00 am
Location: LANCASHIRE UK

Re: Static Timing - Boyer

Post by dave16mct »

I think you should set it at full advance ie 27%. The black box will retard it to start and tick-over.
Dave.
User avatar
clanger9
Posts: 1165
Joined: Sat Jun 20, 2015 9:38 am
Location: Chester, UK

Re: Static Timing - Boyer

Post by clanger9 »

That's right. Set it at full advance and it'll retard automatically for starting. Somewhere between 3/16" and 1/4" BTDC in your case.

If you've changed the compression, it's probably worth playing with the timing. You can rotate the Boyer plate while it's running to find the sweet spot. Mine runs happiest with it fractionally retarded from max idle RPM.
1989 Moto Morini Dart 350
1993 Ducati 750SS
User avatar
Martin.S
Posts: 443
Joined: Sun Mar 18, 2018 12:02 pm
Location: Bristol UK

Re: Static Timing - Boyer

Post by Martin.S »

For those who might be interested - here are the parts I made using the Boyer coils from a used Triumph T140 I had lying around
New Ignition 1.jpg
New Ignition 2.jpg
To make the back plate I took advice from this YouTube video -

I have yet to run it though.
You do not have the required permissions to view the files attached to this post.
Locked