Boyer Bransden air gap

TFR Aussie

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I have installed a Boyer ignition on my 1972 306 (256 with a starter) engine (in a 1975B bike) and have the timing rotor hitting the solder on the timing plate.
Too much solder applied?
Does anyone know what the air gap should be and how to check it? Plastigauge I suppose?
Bike won't pull above 4500rpm, seems to be breaking down, changed the original Gil coil that came with the kit already.
Changed main jets from STD 127.5 to 130, then 132.5 & 140. Standard pipes and XS performance pods fitted. Runs best on 132.5, absolute crap on the 140's.
Diaphragm's test ok and carbies have been acid dipped to clean galleries etc.
BS38's with 3 crossover pipes and non linked, choke seems to be sealing but the top crossover in the manual has lines running down, not connected to each other. Should it be that way?
 

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Jan_P

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Putting a thin washer under the timing plate ? if everything else checks out.
Enjoy the beer and cut out from an empty Aluminum can -- drill a hole for the bolt and start stack washers.
( Or soda can )
 

650Skull

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Pictures are self explanatory................The lip on the cam housing doesn't the base of the stand off sit flat. This puts pressure on the plate causing it to bend.............make some a bit longer up with a step in them to keep the plate flat

From Goran Pearsons Photobucket.

I have added you to a Conversation and this has a couple of links in it with a guide to Gorans album

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grizld1

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Goran did beautiful work which should have been unnecessary. Boyer's timing plate is thin and flimsy and only partially supported on the edge of the ignition housing no matter what you do with modified spacers. Better designed ignitions locate the timing plate in the bottom of the housing where it's fully supported. I had the same issue with a warped timing plate; breakup occurred at 6K rpm. I'd reinstall breaker points before I'd buy another Boyer ignition. Fortunately, there are better products available. Take a look at the recent thread on Ignitech for an affordable option.
 

650Skull

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I don't think i would buy one.....but a solution for a problem without having to replace, if new....................Yea i remember the conversation revolving around the warped plate.............@bluzPlayer Regularly getting reminded and publicly accused it is my fault that, that person is no longer here to continue our conversations..........Hence my new avatar.........:laugh:
 
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grizld1

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It was impossible to have a civil conversation with that one, Skull. He insisted the timing plate couldn't warp until I posted a photo, and he never apologized for effectively calling me a liar. I don't miss the arrogant creep. If you had anything to do with chasing him off, you deserve credit, not blame. My guess is that dementia caught up with him. In any case, good riddance.
 

gggGary

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BS38's with 3 crossover pipes and non linked, choke seems to be sealing but the top crossover in the manual has lines running down, not connected to each other. Should it be that way?
NO! they Must be vented to atmosphere.
unlinked BS38s.JPG
 
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gggGary

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Mebby? Venting the float bowls IS critical.
Truth, I cringe when some sez; I dipped in (some chemical) to clean carb.
Dipping may make a carb look pretty but it's not likely to improve it's running ability.
Remove, eyeball and clean using copper wire every piece of removable brass.
Often overlooked, the emulsion tubes, AKA needle jets, the hollow brass tubes the slide needles drop down into. They sit in a small bore and have many cross drillings, often found clogged with ancient gas varnish. The critical forming of an easily vaporized fuel/air emulsion (frothy gas) occurs here. This emulsion is what gets pulled up into the venturi for high speed motor operation. They are a bit tricky to remove and reinstall, held/sealed by a small o-ring on the BS38s, then kept in place by the float bowl flange. That varnish can really lock em in place, I've had to resort to heating the carb body to soften varnish to get em out more than once.
They have VERY precise dimensions a couple enthusiastic taps with a steel drift can ruin em beyond use.
 
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vr3506

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Is there a source/supply/partnumber forbthis small plastic part?
i marked it with a “ 1 “
 

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TFR Aussie

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Goran did beautiful work which should have been unnecessary. Boyer's timing plate is thin and flimsy and only partially supported on the edge of the ignition housing no matter what you do with modified spacers. Better designed ignitions locate the timing plate in the bottom of the housing where it's fully supported. I had the same issue with a warped timing plate; breakup occurred at 6K rpm. I'd reinstall breaker points before I'd buy another Boyer ignition. Fortunately, there are better products available. Take a look at the recent thread on Ignitech for an affordable option.
I've just about had a gut full of this Boyer crap, I have fitted Sachse systems to both points and Bosch ignition Ducati's with great results in the past.
This thing has already eaten the blue switching box while I was trying to do a compression test and grounding the plugs failed and now the warped plastic plate! I replaced the Gil coil that came with the kit too just on reputation (and while I've been chasing this problem) just to eliminate it.
A local bloke here in Adelaide, South Australia, Tri Spark has been making systems for Triumph's with a great reputation for years has now produced a system for XS650's. I will grab one of these I recon to replace this Pommy crap. https://www.trispark.com.au/compass-ignition-for-yamaha-xs-650-1970-1985
 

TFR Aussie

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I contacted Boyer and asked them about air gaps and if they knew how I could straighten their warped stator plate.
My question and their answer is below. Nothing about straightening the plate, just buy another.
PS I have no float in the shaft and 1mm +- .5mm clearance sounds like it may be a little bit critical...

I have one of your kits on my 1975 XS650 Yamaha and the stator plate has warped inwards and the magnetic rotor has started to hit the solder on the stator plate. I have put washers under the plate to space it out so it doesn’t hit but now have an uneven air gap. Speaking of which, what should the air gap be?
How can I straighten this?


Thank you for your inquiry.
Distance from the magnets to pins is usually around 1mm, +/- 50% is ok, the gap size is not critical, any uneven gap is averaged magnetically with this system. Check for any excess 'end-float' in the XS camshaft.
Any mechanical contact between the rotor and the plate's solder joints or pins should be corrected, using washers to pack the plate out is ok.
The stator plate can be supplied as a spare part if required.
XS650 Stator Plate part number is STA00157, £43.36 inc worldwide shipping (local taxes may apply).
Regards,
1654926763495.jpeg
 

grizld1

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That sure does look familiar. I bet it would look familiar to Ernie Boyer, too. Just how many pennies per unit would it take to make that timing plate with thicker material that wouldn't be as prone to warping?
 

WideAWAKE

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That sure does look familiar. I bet it would look familiar to Ernie Boyer, too. Just how many pennies per unit would it take to make that timing plate with thicker material that wouldn't be as prone to warping?

This warping seems to be a known problem… it it something that develops over time or usually right out of the gate??

Or possibly both?
 

grizld1

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The first Boyer ignition I installed back in '93 never gave me a problem after 5 years and around 14K miles. The next one, installed on a different bike in 2003, went concave after less than 5K miles. There are several high quality choices made now that don't cost much if any more than the B-B, so there's no reason to buy something that's badly designed and poorly made.
 

TFR Aussie

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The first Boyer ignition I installed back in '93 never gave me a problem after 5 years and around 14K miles. The next one, installed on a different bike in 2003, went concave after less than 5K miles. There are several high quality choices made now that don't cost much if any more than the B-B, so there's no reason to buy something that's badly designed and poorly made.
If only I knew then what I know now...
 

grizld1

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Yep, I had to learn the hard way too. The sneaky part of the troubleshoot was that everything looked fine under the strobe and power delivery was clean, so I dismissed the ignition as the trouble source and wasted time fooling with the carburetors. I only removed the timing plate because I couldn't think of anything else to do after the misfire was unaffected by carb cleaning (unnecessary, but I gave the VMs I was running some blasts of spray solvent and compressed air anyway), and fuel level, valve lash, compression, and pressure retention all checked out fine. My wife claims that the air over the barn turned blue for 200 feet up as I expressed my delight with Mr. Boyer and his minions.
 
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