BSA b50 Boyer

I can barely walk today let alone risk kicking that bike over again with the Boyer fitted!!
Does anyone know where I could get genuine or stronger springs for my AAU unit in the UK?
I'm assuming they are the same springs for all side points British bikes?
Cheers
 
Seems I've been lucky as the previous owner had fitted a Boyer Mk IV to my B40WD. Never had any problem with that. Both B44VS still goes as they should with points and working Zeners.
 
Mike40M said:
Seems I've been lucky as the previous owner had fitted a Boyer Mk IV to my B40WD. Never had any problem with that. Both B44VS still goes as they should with points and working Zeners.
Click to expand...
I believe the Boyer mk 4 is a lot better than the mk 3
I have now refitted points and a 12° AAU unit (should be 15° really) but I can't get it to fire as yet because
I can't give it a proper kick
 
kommando said:
This is due to the procedure you are using is making sure the boyer does not go to sleep and the boyer sees the slow movement as a kick not a slow movement.

So try this, do not turn the ignition on until the piston is just past TDC, so with the ignition off as you pass TDC there will be no spark and no kickback. Then turn the ignition on and take the full blooded kick.
Click to expand...
Maybe a stupid idea
But suppose I had a switch that could reverse the black and white black yellow wires from the pickup to stop it advancing
Then switch back once running?
I only ask because I have become nervous of attempting to kick it through now
 
I have the bike running again on the points AAU unit
But with the same revving on problem
I borrowed some springs off of a really low mileage 12° unit
I'm considering modifying this to 15° to give that a try
 
baz said:
Maybe a stupid idea
But suppose I had a switch that could reverse the black and white black yellow wires from the pickup to stop it advancing
Then switch back once running?
I only ask because I have become nervous of attempting to kick it through now
Click to expand...
Ok scrub this idea the bike won't even fire with the pickup wires reversed
But switching on just before a kick does
No kicking back yet
Cheers
 
All these units are the same of a muchness, however the B44 is 29 degrees BTDC Fully advanced and B50 is 34 degrees FA. So what works in a B44 when advanced 5 degrees in a B50 is also 5 degrees less retarded when you kick. Couple that with increased compression and a lighter flywheel and its kickback city.

I would twin plug a B50 and retard the ignition for easy starting. Have that on my B44 and it sometimes fires just after TDC when I try to get TDC before kicking.
 
kommando said:
All these units are the same of a muchness, however the B44 is 29 degrees BTDC Fully advanced and B50 is 34 degrees FA. So what works in a B44 when advanced 5 degrees in a B50 is also 5 degrees less retarded when you kick. Couple that with increased compression and a lighter flywheel and its kickback city.

I would twin plug a B50 and retard the ignition for easy starting. Have that on my B44 and it sometimes fires just after TDC when I try to get TDC before kicking.
Click to expand...
I have now fitted an on off switch on the handlebar next to the twist grip
This seems to be working ok
Or I should say it works for me as it's easy to flick on just before I kick
And no kickback as yet
Cheers
 

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