Anyone running boyer ignition?

[warren3200gt]

A guy has given me his 650 to try and get running properly.
Unfortunately he gave to a dealer first who just stuffed it full of non genuine ebay jets etc. Fortunately they gave him everything they took out which I have re instated and set the carbs up both balanced and colourtune. It runs a lot better now but has a chronic misfire at 3 - 3.5k revs on cylinders 2 & 3. its got stock airbox so it's not a typical pods flat spot. Relay mod has now been added so full battery voltage to the coils.
So moving onto timing, it's running a boyer bransden system which is not something I'm familiar with fault finding on. They seem to either work or not.
So, strobe on 1&4 getting good consistent strobe flashes every revolution. Switch the strobe pick up to 2&3 and it seem to miss every 4th or 5th revolution.
So on tickover it's hardly noticeable but at the vibration resonance at 3 - 3.5k it virtually cuts out entirely on that coil. Nothing appears to be loose or have a bad connection.
Problem is boyer has electronic advance built in so the original mechanical advancer is not present so I can't just chuck a Dyna plate on it to confirm its an ignition issue.

Anyone got any pointers on these ignition systems?

[z1bman]

Have you swapped over the coils ?

[warren3200gt]

I've tried that and the fault stays with 2&3. I'm tempted to disconnect all the boyer stuff and "borrow" an advancer and Dyna from one of my 650's just to confirm it's a ignition system fault.
But thought if anyone had experience with these systems it might be a known issue with a known, simple hopefully, remedy.

[Al]

If the strobe has an inductive pick-up with an arrow pointing to the plug; either try turning it over or use it the conventional way on the other lead of the same coil. Meaning if you only tried spark plug lead number 3, try it on number 2 and see if you get the same result.
One HT lead is effectively positive and the other negative which foxes the uni-directional pickups on most strobes.
Without being condescending, a remote battery for the strobe removes pulses in the system and i hear you need to do set-up in the dark because they are optical systems as far as i can remember.
AL

[kev edwards]

Warren contact Boyer, they are pretty good to deal with and are just outside Maidstone, I've used a lot of Boyers over the years and never had problems, check the pick up for resistance to eliminate it, chances are at some stage the box has been wired up wrong and could be toast.

[warren3200gt]

Yep, running the strobe from a remote (car) battery and tried it on 1&4 leads which gave the same result. Then on 2 & 3 leads which gave the same "misses". Haven't tried it with the arrow reversed though, but not sure it would change anything? Or would it?

It's almost like at low revs there's some resistance which increases with revs until the revs are higher enough that they out pace the resistances ability to build up and it functions fine.
Not sure that's an achievable scenario but describes what I'm finding.

[warren3200gt]

Warren contact Boyer, they are pretty good to deal with and are just outside Maidstone, I've used a lot of Boyers over the years and never had problems, check the pick up for resistance to eliminate it, chances are at some stage the box has been wired up wrong and could be toast.

Spoke to them today Kev, apparently they don't allow customers to talk to their tech guys only by email. Have sent them an email and included videos of the strobe on each cylinder which clearly shows the issue. Not had a response yet.

[z1bman]

http://www.boyerbransden.com/faultfindi ... s%20faulty.

[KWACKERZ1]

Hi Warren ,
I might have a boyer kicking about if you want to try it.
Likely to be off a 1000 though.
Drop me a pm if you need it.

[warren3200gt]

Thanks for the info and offers guys but just to definativley rule it in or out I swopped in a Dyna system off of one of my bikes and the issue remained so pretty much ruled out the ignition system.
So here's the issue.
Poor running on number 3. Carbs have now been ruled out as I've had them off the bike and gone through completely....twice. Ive swopped back in genuine mikuni parts which a kawasaki dealer swopped out in favour of ebay junk.
Ive tried different/swopped plugs, caps, leads, swopped the coils with each other and it remains at no3. Weird thing is with the plug in I get absolutely zero on the strobe, no firing from the cylinder, other three are fine. With the plug out on the cylinder I get spark and broken stobe indication. So swop 2 ht with 3 and issue stays with 3. As a "just because I haven't tried it" I swopped the 2&3 coil polarity which shouldn't make any difference and.... it didnt .
So swopped it back and checked for strobe on no 3 ht lead, still nothing. However when I swopped 2 & 3 ht this time the issue moved to 2. So did the polarity swop and swop back "reset" something in the coil but I don't see how or what.
So plan is tomorrow to swop out the "maybe suspect" emgo coil for a parts bin original. If it resolves it then a pair off quality coils go on the shopping list.
Its been a frustrating and illogical results kinda day. Fingers crossed a coil swop back to an oem one moves it forward!!!

[Al]

Yep, running the strobe from a remote (car) battery and tried it on 1&4 leads which gave the same result. Then on 2 & 3 leads which gave the same "misses". Haven't tried it with the arrow reversed though, but not sure it would change anything? Or would it?

Have a look at the orientation of the; 'down' 'across' and 'up' arrows with respect to their plugs here.
If you have the arrow on the inductive pick-up poining toward the plugs; on one of them it will be the wrong way up!!
The HT or secondary circuit is a closed loop on twin tower coils which can be misleading when using a strobe.
Earlier this year i had an internal short (between primary and secondary) in a previously perfect Dyna coil and it had me scratching my head for a week of days.
It gave similarly incomprehensible results to those you are seeing.

Coil sparks pos and neg.png (166.34 KiB) Viewed 28899 times

AL

[warren3200gt]

Thanks Al, but I've eventually found the cause. The boyer system is fine. My strobe, although it has an arrow on it, must be dual directional.
I've now got good consistent strobe on all 4 plugs at upto 5k rpm, the highest I am OK to rev it not under load and its running without missing a beat.
The cause was a new one to me and a little baffling. After swopping a parts bin oem coil the symptoms disappeared. It transpires that the coil fitted when bought round to me breaks down only on one side and only at certain revs. Took some finding!

[Al]

The cause was a new one to me and a little baffling. After swopping a parts bin oem coil the symptoms disappeared. It transpires that the coil fitted when bought round to me breaks down only on one side and only at certain revs. Took some finding!

That was one, if not my only conclusion when looking at mine. It turns out that the really cleaver part of the twin tower coils / wasted spark set-up is that its not entirely wasted! Meaning that the spark energy is focussed on the area or route of highest electrical reistance. In practice this means that on a cylinder not under compression, the spark just bleeds across to complete the circuit. The spark plug in the cylinder under compression has a greater resistance to the flow of energy and the available force is concentrated there.

If there is a difference between the static resistance of the two; HT leads / caps/ plugs combo's; the spark energy will be disproportionately directed to the point of higher resistance.
This can give the impression that one side of the coil has failed but i dont think that is possible as i mentioned above; the secondary or HT side is a merry-go-round / sealed loop. If one side fails the other must. That does not mean that both necessarily drop out but one is more likely to malfunction than the other. That failure may or may not swop from one to the other depending on where it finds the highest resistance, swopping the leads on the coil may not show it up!!

I wish i was more electrical savvy and i could avoid using terms like; merry-go-round

AL

[warren3200gt]

Yeah electrickery is not my strong suit either. I was thinking the non common parts between 2 & 3 was where the output splits to connect to the ht's. So maybe a dry joint from the internal spike to the ht on number 3 which would get worse with heat/frequency.
Electrickery is black magic or should that be blue magic.

[Bill P]

Thanks for sharing that it made interesting reading