Hi all A65L would not start battery was charged up but would not kick over put some ingnition spark testers on each plug (red plastic plug type cap with I think a diode inside goes between plug and cap) tried to kick it up but the diodes did not flash took plugs out with testers still on rested them on cylinder head kicked it over the testers and plugs flashed tried several times plugs in and out but would only flash on cylinder head bike has boyer ignition and duel coil,strange they would not spark under compression. Any ideas please Roy
I would suggest a test on the battery, you may have low voltage. Boyer have a website that has all the answers on problems like this. Good luck.
Thanks A10 JWO the battery was fully charged, cannot understand why they spark when earthed to the cylinder head but will not in the plug hole, could something be slipping when kicked over when plugs are in situ and causing compression.
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Is it the plugs. I had a 'duff' set straight out of the box.
Mike 8) 8) 8)
Some plugs will not spark under compression, something I don't understand but fact.
Hi - is the engine actually turning over when you are kicking? It might be the clutch slipping under compression. John.
Thanks for the replies, JohnJag going to look at clutch after trying different plugs the only thing I can think it might be is the clutch. Roy
I know oil should be in the primary chain case but should the driving plates be wet mine are just damp if they should be wet would a soak in oil help.Roy
Hi all, johnjag yes the engine is turning over when kicking but I was like you thinking it might be the clutch slipping under compression so I put new drive plates in and cleaned the driven plates up but still the same, testers and plugs flash and spark when earthed to cylinder head but not in situ,more help wanted please.Roy
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Hi.
I cant be specific about this ---lack of knowledge---But you might just need a plugs with a different power/heat range. Guess you'll need to read that up.
Mike 8) 8) 8)
Thanks Mike not trying to start it at this stage so using new plugs the same as it had when running, just want both plugs sparking when in the holes and under compression
Thanks for your replies sent a E.mail to boyer bransden didn't get a good reply, but still can't get it in my mind how the plugs and testers spark and flash when rested on cylinder head and will spark and flash with one plug and tester in the plug hole but not with both plugs , will have to go to back of shed for a while.Roy
Just trying to think my way round this. Other posts lead me to believe that Boyer use a wasted spark system. Wouldn't this mean that you would need double the voltage to achieve breakdown across two gaps? If so it would explain not sparking when two plugs are in and sparking when one is out of the hole. The breakdown voltage is roughly proportional to the pressure times the gap length. So a combination of a wasted spark system and a low voltage from the electronic ignition would explain the behaviour, but not how to put it right. A capacitor failed somewhere?
Adrian
Wow thanks Adrian what a technical reply, way over my head but I get the meaning, going to put it on back burner for a while . Roy
I don't think that the Boyer unit would introduce a problem with breakdown voltage - although it sounds as if the problem could be related to that if the plug sparks under no compression but doesn't under compression as you have found.
The Boyer system is designed to fire both cylinders at the same time (hence wasted spark as one is on exhaust stroke) and does this either using two (typically the original) 6V coils re-wired in series. Each coil still receives a 6V potential across it to fire it (assuming both coils are good and have same resistance) so each should generate a good spark.
The idea behind this I believe was to allow the original 6V coils to be re-used. However, if one is damaged or they have different resistances on the low tension (6V) coils for some reason then this could affect performance as the voltage applied across each coil would be something other than 6V and 6V - e.g. 7V and 5V. This could be checked using a multi-meter to verify that the resistances are the same on each coil.
An alternative configuration is to use a single, dual-output 12V coil instead as commonly fitted to modern twin cylinder bikes. I used this on my last A65 to good effect.
It does sound from your description as if a weak spark might be at least part of the problem. Have you tried swapping combinations of which plug/coil is sparking loose on the head and which tight in the head? That might throw a bit more light on the problem if the problem moves with the plug or coil used....
Cheers,
Bernie
Hi all, I have read Boyers fault finding page and it says the ignition will not fire under 200 revs I have never built an engine up could there be a problem in the engine that wont let it rev to 200 or over when cranking it with kick start, as I have said before they will flash and spark but not under compression with both plugs in, new clutch drive plates have been fitted dry with the 3 adjusting screws flush with their studs but thinking on not adjusted the centre push rod. thanks for reading must be getting boring now.Roy
Do you think that your clutch might be slipping when kicking over under compression such that the engine isn't actually turning?
I guess that could explain it but I think that you'd feel the slipping as you kick and wouldn't hear the expected sounds of intake and exhaust as the engine turns over. If in doubt maybe tighten the clutch nuts down on the springs as a temporary measure and make sure that there's some free play at the clutch rod.
Cheers,
Bernie
Thanks Bernie will have a go at adjustment when the weather picks up. Roy
Hi all, adjusted the clutch Bernie but just the same, I did notice with the testers and plugs in situ when I turned the ignition on the testers flashed so I am thinking the ignition system is ok, when cranking with kickstart every thing turns on the primary side and can hear the pistons moving, if I have to strip the clutch down (weather, time and room permitted) what might be making it slip slightly not getting up to 200 revs under compression. thanks Roy
Thanks all for your input, the problem was as some of you said was duff plugs, bought some more (from a different supplier and cost more) and new caps and fired up second kick,bring on the good weather.Roy
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Well we got there in the end---Brilliant (duff new plugs aint that rare)
Mike 8) 8) 8)