Alternative for timing a Boyer ignition

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Beach

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I didn't like the idea of running my Norton at 5000rpm while trying to time the Boyer ignition so I looked for an advance curve so it could be timed at a lower rpm...I found this info on a website and could probably use the info to time at lower rpm...Hope this information can be useful to others..

http://www.nocnsw.org.au/technical/igni ... ando-boyer
 
Yes that is the timid women's way to check with a time light. With the stable cam chain support and smooth combustion in a steady mounted engine of Commando with indexed degree wheel'd crankshaft and dead on reading tach needle/drive and the famous linear response of one boyah to another electronics, this method could be accurate enough within a hand full of degree's and nil risk to throw a rod from excessive unloaded rpm doing it single handed. Some day might take it to a shop or rally to let them verify boyah reaches its full predicted adv limit w/o over shooting for unheard detonation or more sluggish response than expected.
 
Beach said:
I didn't like the idea of running my at 5000rpm while trying to time the Boyer ignition so I looked for an advance curve so it could be timed at a lower rpm...I found this info on a website and could probably use the info to time at lower rpm...Hope this information can be useful to others..

http://www.nocnsw.org.au/technical/igni ... ando-boyer
why dont you like to run your commando at 5000rpm?
 
The timing map for a Boyer may vary from a Mk1V to a micro digital, the actual revs that a Boyer reaches full advance, may vary from rev counter to rev counter and from Boyer to Boyer, so general advice is to set the Boyer on the full advance mark, when you see that the Boyer has stopped advancing.
 
Just rev it up in a few blips somewhat over 5 grand to make sure its reaching full adv and not more is all that is required, not holding it over 5000 which is nerve wracking to us all but a total non issue to a proper assembled engine. Its oil surfing everything and crank is not near its wipe out flinging and mixture is well stirred and hi flowing exhaust flushes out carbon like a hillbilly tune up. Thick carpet under center stand stops the Cdo floor dance which everyone should experience at least once for the lasting thrill that may be another unique Cdo phenomena. Someone should video this sliding dancing for our entertainment.
 
If the Boyer has fixed timing, you can strobe it at 4000 RPM or even lower. The important thing is that the timing should not vary while you are tuning the carburation. A change in timing can produce the same symptoms as changing the mixture. When you are strobing the ignition, you will see if the timing changes with the revs. You need four hands to do this job - get a friend to help.
I always choose ignition timing to suit the fuel, and tune the carbs to it. Don't try to change two things at once.

I don't have a programmable Boyer ignition, however if I did, I would simply choose the revs I normally use when riding on an open highway, and set the timing at those revs to the usual figure specified by Norton, and then tune the carburettors to suit. If you reprogramme the ignition system, or change the exhaust system or cam timing it means retuning the carbs - very difficult using Amal needles.
 
Boyers are not programmable.

Time when your strobe shows you that the Boyer has stopped advancing. The Boyer will then set the static timing near stock. The Rickover stabiliastion feature of the Boyer Microdigital make it a mugs game to try and strobe a Boyer at tickover.
 
Down/dirty single hobot refined by much practice method for boyah is set by instructions to get started then creep up initial adv till hints or distinct scary back fire then creep in retard over a number of kick offs til just no hint of back fire and lock it down. At this point I mark the trigger plate position and that's that. But for mental and emotional entertain purposes only, I straddle saddle with Cdo on its tires not stands then kick off with time light on DS on its own battery supply aiming it with LH and working throttle with another free hand to rev up over 5000 enough to see where the thing tops out and noting degree by my mark on Alt. rotor or the double checked by degree wheel factory dial. I can't watch tach doing this of course w/o someone else sharing the tasks. Go ahead and make my day and tell us how it went with wife helping out...
 
I got it timed and now understand what is going on...I blipped the throttle and made sure the timing didn't go over 31 degrees BTC..Should be good to go now I would imagine..
 
acotrel said:
I was under the impression that Boyer offer optional advance curves ?


None of the Boyer models offer optional advance curves. Some of the BMW airhead ignitions offer up to 16 different curves, but this is a reaction to market demand on airheads for different curves to fit engines that have been dual plugged.
 
Boyah's that fit Brit 360' twins have to have a slightly tamed curve rise for the slower combustion chambers of non Nortons not to detonation. Jim Schimdt has a solution for that if ya care to blast out turns harder. One thing Boyah offers that most don't is rev limiter feature, which costs about as much as new boyah but could save some engines.
 
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