Boyer logic

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Once again My Boyer leads me to doubt.
I have had it installed and running but I missed something, the running seems alright but could be better.
Here's what I did:
Firstly the degree scala needed replacing on the primary (which is in the proper place).
A new rotor has been fitted due to suspect core.

TDC was found then with a degree wheel rotating the back wheel forward I set the crank to 31 degree's BTDC.
The magnet rotor was set horizontal and the pick up stator plate was positioned with the hole over the white dot.

At this stage things stand, I tried to time with a strobe using individual rev's, 2000, 2500, 3000 and 3500 as a beginning to keep the neighbors calm.
The Boyer advance for these rev's I will list and my true readings are beside.

Rev's Boyer Advance True Advance
2000 16.3 (16) 32
2500 19.6 (20) 38
3000 22.8 (23) 39
3500 26.1 (26) 41

Does this mean the engine has far too much advance, which I can't understand. Did I make a mistake with mounting the timing.
On starting it does tend to backfire only sometimes though and kick back.
Should I try retarding the ignition, by that I mean turning the pickup stator anti-clockwise.

All supporting information gladly sought as I am stumped!

John
 
The Boyer static timing is a starting point and is normally too advanced hence the need to strobe and adjust. So based on what you have retard the Boyer and retest aiming for 31 at 5000 rpm, adjust until you get this.
 
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Question on strobing: How does one accomplish this without the aid of another person? Can't watch the strobed alternator rotor through the primary cover opening whilst holding throttle and watching rpm?!?!
 
I have found they are much nicer set at 28 degrees BTDC. No kickbacks too.
 
Question on strobing: How does one accomplish this without the aid of another person? Can't watch the strobed alternator rotor through the primary cover opening whilst holding throttle and watching rpm?!?!

Sit centre stand on a rubber tile or carpet even, then operate the throttle with one hand and strobe in the other, the tile/carpet will absorb the vibrations enough so the bike stops doing walkies at 5000 rpm and reving the bike until the advance slows down will be close to 5000 rpm.
 
Sit centre stand on a rubber tile or carpet even, then operate the throttle with one hand and strobe in the other, the tile/carpet will absorb the vibrations enough so the bike stops doing walkies at 5000 rpm and reving the bike until the advance slows down will be close to 5000 rpm.

I sure would like to se a picture of you doing that, at over 60 I am no longer that bendy :)
But the idea is good especially if the throttle can be locked at revolutions e.g. 2000, 3000, 4000 and 5000.

A friend of mine helped me last night, we started at 5:30 and were finished to the chimes of the clock at 8.00. That is curfew where I live so we just made it.
I was happy with the end results, they should be bang on but there may be room for adjustments like Fullauto says. Must take her for a ride tonight.

John
 
Question on strobing: How does one accomplish this without the aid of another person? Can't watch the strobed alternator rotor through the primary cover opening whilst holding throttle and watching rpm?!?!
It can be done
I have always strobed my bike on my own, but I have my own timing mark on the stator so I time it with the outer primary cover removed
I have no center stand so I don't get the bike walking problem
 
It can be done
I have always strobed my bike on my own, but I have my own timing mark on the stator so I time it with the outer primary cover removed
I have no center stand so I don't get the bike walking problem
Another advantage of having Don's (madass140) single cable gantry is the ability to operate the throttle from the left side of the bike by lifting the operating arm. Or you can just wind up the tickover adjuster.

Cheers,

cliffa.
 
Question on strobing: How does one accomplish this without the aid of another person? Can't watch the strobed alternator rotor through the primary cover opening whilst holding throttle and watching rpm?!?!

That's what grandchildren or next door neighbors or people out for a walk or if you have one wives are for :)
 
Question on strobing: How does one accomplish this without the aid of another person? Can't watch the strobed alternator rotor through the primary cover opening whilst holding throttle and watching rpm?!?!

I don’t want to sound “obvious,” but you stand to the left of your idling Norton with the strobe in your left hand.

Holding the throttle in your right hand and watching the rev counter, open the throttle slowly until revs reach 5000 rpm.

Holding the throttle steady, bend down, shine the strobe on the marks and look at them.

Did you really need to be told all that?
 
I sure would like to se a picture of you doing that, at over 60 I am no longer that bendy :)



I doubt my Commando's handlebars are any lower (Edit: When I made the video) or my arms significantly longer than yours so I don't know why the apparent difficulty even when "over 60" (as I am).
It shouldn't take more than a few minutes to set electronic ignition even when working alone as I do. There's no need to look at the revcounter as your ears should be telling you what the engine is doing!



But the idea is good especially if the throttle can be locked at revolutions e.g. 2000, 3000, 4000 and 5000. A friend of mine helped me last night, we started at 5:30 and were finished to the chimes of the clock at 8.00. That is curfew where I live so we just made it.



If you've been trying to check/set it every thousand RPM then no wonder it took so long!

The Boyer advance curve is preset and the advance curve can apparently vary slightly from box to box so all that needs to be done is to check at *full advance*.

Edit: Before someone points out that the Boyer Micro MkIII/IV never completely stops advancing, the strobe image becomes increasing unsteady at higher RPM.
 
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Well Triton I am glad you can, I am a kind of wee guy and my Commando has export bars which are high and long. It is just I cannot imagine doing this act alone.

As marshg246 says helpful people gratefully accepted but my wife Ooooh No! Mine is like one I read in a post who took a hammer to the tank for no reasons explained :(
 
A couple of points: I assume it’s a typo where you say you turned the rear wheel forwards to get to 31 btdc? You have to turn it backwards.

Where is the white paint dot that you lined up?
The instructions that came with my Boyer say to line up the centre of a magnet with the hole in the stator plate.
 
Where is the white paint dot that you lined up?
The instructions that came with my Boyer say to line up the centre of a magnet with the hole in the stator plate.

....Normally marked by a white dot on each magnet.

Boyer logic
 
I don’t want to sound “obvious,” but you stand to the left of your idling Norton with the strobe in your left hand.

Holding the throttle in your right hand and watching the rev counter, open the throttle slowly until revs reach 5000 rpm.

Holding the throttle steady, bend down, shine the strobe on the marks and look at them.

Did you really need to be told all that?
I have log arms. Still getting down low enough to see the timing marks without parallax error and operating the throttle is difficult. It is impossible to also see the tach and for me, holding it at an RPM will getting into position is impossible - I need my hands free to get down.

But my real issue is that getting up and down, going to the other side of the bike to make the adjustment, and then getting back into position is hard. When I do it by myself, I don't look at the tach. I twist the throttle until the engine doesn't advance any further. It is MUCH easier to set the timing with a young person on the drive side giving me hand signals and me adjusting and controlling the throttle. Then for a final check, I check the marks with them controlling the throttle and me giving them hand signals.
 
A couple of points: I assume it’s a typo where you say you turned the rear wheel forwards to get to 31 btdc? You have to turn it backwards.

Not a good assumption. When static timing to 31 degrees BTDC, you turn the crankshaft backwards past 31 degrees BTDC, then forward to 31 degrees BTDC. That’s to take up the backlash in the camshaft drive.
 
When timing a Boyer, don’t watch the Rev counter, just time the bike on full advance, WHEN THE Boyer stops advancing, it’s easy to see with the strobe.
 
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