Author Topic: Boyer Ignition - Again  (Read 2021 times)

Offline paulbaker1954

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Boyer Ignition - Again
« on: October 30, 2017, 01:04:47 PM »
Just taken the plunge and ordered the full kit with Micro coils after months of deliberating !!

I have a question re plug caps mine are NGK purply colour ones (sorry for the crap description)

Are these OK for use with the BOyer system? Is there an easy way to check them?

Cheers all
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Offline deltarider

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Re: Boyer Ignition - Again
« Reply #1 on: October 30, 2017, 01:39:18 PM »
Just check they're 5kΩ, unless you run "R" sparkplugs.

Offline paulbaker1954

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Re: Boyer Ignition - Again
« Reply #2 on: October 30, 2017, 01:49:34 PM »
Cheers Deltarider just what I needed  :)
If you think there's light at the end of the tunnel it's usually another train !!

2016 Yamaha MT09 Tracer
1971 Honda CB500 Four K0

Offline Johnwebley

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Re: Boyer Ignition - Again
« Reply #3 on: October 30, 2017, 02:30:14 PM »
the Boyer gives a great fat spark,(or at least mine does)

 and seems to make my engine run sweetly ,with even low down pull !!!

 I run slightly larger plug gaps,
also the resistor plug caps can burn out with age,seriously increasing resistance,so check the reading
lifelong motorcycle rider,and fan

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Re: Boyer Ignition - Again
« Reply #4 on: October 30, 2017, 03:59:21 PM »
The Boyer systems appear to be well regarded generally, be interesting to see what you feel about it when installed Paul.

John,  I was wondering about your decision to increase the plug gaps,  is it something recommended for this system? For a long time I've thought in a similar direction but more recently come to doubt that and believe I don't want to do that now.

Nigel.

Offline kevski

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Re: Boyer Ignition - Again
« Reply #5 on: October 30, 2017, 04:10:38 PM »
These boyer systems are really good, i have used them on all my bikes with the exception of my Big Zeds, there is absolutely no reason to increase spark plug gap as the original gap is set for optimum performance and efficiency, if any thing it would be detrimental, you can use resistor caps as long as you don't use resistor plugs.

Offline Johnwebley

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Re: Boyer Ignition - Again
« Reply #6 on: October 30, 2017, 05:33:27 PM »
The Boyer systems appear to be well regarded generally, be interesting to see what you feel about it when installed Paul.

John,  I was wondering about your decision to increase the plug gaps,  is it something recommended for this system? For a long time I've thought in a similar direction but more recently come to doubt that and believe I don't want to do that now.

Nigel.

 my feeling was it generated a big fat spark,so it should give a better burn with a wider gap,
the sohc heads are pld fashioned Hemi shapes,not pent roof ,so could help.

 and anyway,it seems to work with me
lifelong motorcycle rider,and fan

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Re: Boyer Ignition - Again
« Reply #7 on: October 30, 2017, 06:31:02 PM »
I was just curious to get another informed point of view John as you're happy with how yours runs.

I've felt the same with regards to combustion chamber shape and fatest spark theory until recently.

I'll not drop it onto paul's thread though but put it somewhere else.

Offline petermigreen

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Re: Boyer Ignition - Again
« Reply #8 on: October 30, 2017, 07:56:03 PM »
Thanks for updating Paul. I'm still umming on whether to get the kit as bikes running good on points. Let us know how you get on once fitted and run.
Peter

Offline deltarider

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Re: Boyer Ignition - Again
« Reply #9 on: October 31, 2017, 07:54:45 AM »
If you look at the wiring scheme of your bike, you'll understand that an electronic ignition is nothing but a switch, so don't have too high expectations. A transistor just happens to switch faster. Some folks claim improvement over stock, but often forget to mention they've changed sparkplugs at the same occasion. Mind you: a fresh set of plugs can work miracles. My homebuilt transistor module gave me a noticeable improvement at idle and at high rpm, especially near red zone. Mid range rpm, mwah, I'd say it's the same as stock. Below a pic of testing my then repaired transistor ignition and a pic of how you can check your spark is at least 7mm. The spark in a running engine is determined by the wideness of the electrode gap and the hellish 'atmospheric' conditions inside the combustion chamber. The sparkplug only has to ignite a very small amount of mixture between its electrodes. The burning flamefront will take it from there. 
« Last Edit: November 01, 2017, 11:57:43 AM by deltarider »

Offline AshimotoK0

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Re: Boyer Ignition - Again
« Reply #10 on: October 31, 2017, 08:37:36 AM »
Agreed Deltarider....  for a much juicier spark you need CDi. One of these days I am going to build another unit for my 400/4 like the one I designed back in the late 70's but was basically cribbed from the original 400 DC inverter driven Kwak H1 triple design from the late '60's. My 400/4 currently has the Boyer system that was on it when I bought the complete bike for a hundred quid in 1985 from a Brit bike dealer who's words were something like "Give us a hundred quid  and for Gods sake  get that Jap Crap out of here ...it's bad for my reputation."  Like all of that electronics tackle by the way...a man after my own heart ...  you'll be joining Anoraks Corner next ... hope that's not the kitchen table or you may get yourself in bother  ;D
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Offline deltarider

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Re: Boyer Ignition - Again
« Reply #11 on: October 31, 2017, 08:42:23 AM »
Ha, I'd be interested to learn about your CDI, so keep us posted. Will it be a multispark?

Offline AshimotoK0

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Re: Boyer Ignition - Again
« Reply #12 on: October 31, 2017, 07:40:25 PM »
Ha, I'd be interested to learn about your CDI, so keep us posted. Will it be a multispark?

My 1970's one wasn't but a possibility with modern  micro-controllers  etc........  this  looks to be well designed and documented and is multi-spark.  :)

http://m1n1.de/html/umcdi.html
“Alright friends, you have seen the heavy groups, now you will see morning maniac music. Believe me, yeah. It’s a new dawn.” Grace Slick, Woodstock '69 .. In the year of the Sandcast.

Offline deltarider

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Re: Boyer Ignition - Again
« Reply #13 on: October 31, 2017, 08:40:37 PM »
Ha, interesting stuff and that in a wonderful Alec Issigonis setting. I have to study it a bit more in detail but just two sparks at around 4500 rpm... I dunno.

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Re: Boyer Ignition - Again
« Reply #14 on: October 31, 2017, 09:26:46 PM »
Interesting reading Ash, the section about multiple sparks to extend the ignite time is particularly relevant to what I was saying back there about plug gap.

If you use a wider plug gap (on non cdi systems) than idea,l then it shortens the spark duration,  which affects how the mixture propagates a flame front.

If you don't get the cylinder to burn as designed then you head towards combustion problems.

Generally it's written that the fatter and hotter the spark is,  then the better system you've got. Some of the things the ignition has to achieve run counter to that.

 

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