Should I ditch the Boyer?

hi all
been having a few problems,it was running fine , took it for an mot it was stalling running a bit rough
always seemed to start eventually...
anyhow fitted a service kit to each carb, o rings on the mixture screws and float chamber gaskets, i checked the float heights and they were ok so i left them alone-fitted 2 new plugs as it had an unmatched pair
it seemed to start easier and ticked over ok so a couple of days later i got it out ready for my 1st ride since buying it-it started and was only running on 1 cylinder and popping/backfiring out of the other
back in the garage and i left it-basically i was not in the mood to look at it !
anyhow few days later i tried it again now all it will do is fire up and die after a few seconds,wont start again unless you tickle the carbs again then it repeats the symptoms starts runs and dies
ive been reading good reports about the tri spark and was going to buy one, theres 2 versions so i need to check out the one i need 1st
reason for this was the easier start and better advance curve and because ive read the boyers can play up causing misfires and difficults starts.or theres a chance of course its something ive done ?

If you are sure you're getting gas, did you actually check for consistent spark at the plugs? A compression test is also simple, but probably not an issue here. If a boyer actually goes bad it seems about one in a million, but can happen. I would tend to think you have an electrical issue somewhere besides the boyer itself. You need to rule out your wiring before laying down 300 bucks on an ignition that may not fix the problem. Example: I've had faulty ignition switches cause problems like your talking about or a bad circuit like the kill switch, but like I said rule out the easy stuff before buying expensive parts. I'm sure a few others with a lot more knowledge will offer suggestions better than mine, but you've got a starting point. Another idea is if you can get a hold of someones boyer box and swap them, see if the problem disappears. There are also some good trouble shooting write ups on boyers web site. I've run boyers, pazons and tri sparks before and they all work well when the wiring is in tact.

Hi Matt,
Sounds like idle jet(s) blocked. Will it run with throttle open at say 2500 +? Worth poking them thru with a pc of wire (0.017" I think, I have drills to do mine) Still could be Boyer connections at the stator plate or any bad earth or neg connection associated with ignition. battery, keyswitch, kill switch, all those.

Battery should be tested by loading it. Put the lights for three minutes and with them still on Voltage test the battery anything under 12 would be bad.
Now test the petcocks flowing anything that makes the stream of gas flutter is suspect. Check with and without the gas cap on. Use a #78 drill on the jets behind the air screws.Brake clean after this.
Check the kill button for voltage drop if it is still being used. You might what to check this first. (So common)
I could go on for a page of two but replacing the Boyer for a non running bike comes up about page three.

So many things it could be. What are your plugs looking like?
Sounds exactly like they are fouled to me.
I've used a Boyer for over 10 years and never have had one issue.
More info needed
Cheers
david

Thank you for all your tips
a few things i didnt think of there
plugs are brand new and still clean
the fuel taps are both brand new
the idle jets ive removed and cleaned and blew the pilot hole through with carb cleaner and you get a nice jet of cleaner come out of the centre of the carb body inside

although i never ran a drill bit by hand through the hole itself,it wont even run though if you open the throttle half or full it still dies

the battery is brand new yuasa and is left on a bike trickle charge/monitor specially made for bikes and meant to be left on and connected to cycle the battery

didnt think of the kill switch or ignition switch

i guess to test them you just check the input and output voltage and look for a drop across them>?

last time i checked there was a healthy looking spark but tonight when i briefly tried to start it,it didnt even fire once !

The most common reason for a Boyer to fail is through poor voltage. This is usually caused by a bad battery or corroded connectors or switches.
I'd be checking the voltage at the battery and then at the Boyer to see if there's a loss between them.

Hi Matt- I am certainly no expert- but I have seriously abused my bike by letting it sit for years at a time in storage, melting fibreglas tank in fuel, gummy carbs, bad plugs, bad fuel flow- and in every instance my Boyer never let me down. She started up when she had no business starting up. I'd sure try just about all the other solutions before I gave up my little black box for some rusty metal points.... just my two cents. Good luck!

+1 for not being an expert also...but the same symtoms happened to me three weekennds ago. Sparx ignition (absolute crap!), everything running just fine up to my buddy's house, then went to take off from a red lilght and it started popping and coughing AND runninig on one cylinder. Went through a complete diagnosis, not sparking on the right-hand cylinder...ended up changing the coil on that side and...all was well. That fixed that.

The next weekend, bike died pulling into a Cracker Barrel...bike running fine all day up till that point. No spark again, same side. Hmmmm....changed the coil again on that side...and still nothing. My buddy ran to his house and brought back his Pazon control box. Wired it up, with the Sparx magnet and ignition plate still ini place under the points cover and SUCCESS!! At least it got me home. Ordered a new Pazon and Pazon's coils and installed them today. Holy Crap, what a difference! Easy, easy kick to start and the accleration was so much better I found myself looking for another gear past 4th a couple of times in traffic because I swore I was still in 3rd. Can't say enough about the Pazon system...much higher quality....easy set up...and very noticeable improvement in performance.

MATTT said:

hi all
been having a few problems,it was running fine , took it for an mot it was stalling running a bit rough
always seemed to start eventually...
anyhow fitted a service kit to each carb, o rings on the mixture screws and float chamber gaskets, i checked the float heights and they were ok so i left them alone-fitted 2 new plugs as it had an unmatched pair
it seemed to start easier and ticked over ok so a couple of days later i got it out ready for my 1st ride since buying it-it started and was only running on 1 cylinder and popping/backfiring out of the other
back in the garage and i left it-basically i was not in the mood to look at it !
anyhow few days later i tried it again now all it will do is fire up and die after a few seconds,wont start again unless you tickle the carbs again then it repeats the symptoms starts runs and dies
ive been reading good reports about the tri spark and was going to buy one, theres 2 versions so i need to check out the one i need 1st
reason for this was the easier start and better advance curve and because ive read the boyers can play up causing misfires and difficults starts.or theres a chance of course its something ive done ?

Click to expand...

A problem running on one cylinder is almost certainly not the Boyer, because it fires both coils at the same time. Maybe the plugs, wires, coils, I'd bet on a plugged idle jet though. If you can get a set of longer than sparkplug wires you can run the right coil on the left cylinder and vice versa. Switch the spark plugs from left to right too. If you do this and the problem goes away, it was probably the plug wires. If it remains the same it has to be the carbs, or compression. I'd bet carbs, but you can do a compression test to confirm that it's not a tight valve, etc.

-Eric

-Eric

I did a pole on failed Boyer's and didn't see many failures, but I can tell you the coils on the points plates fail from vibration or the wires break! I put a rag under the points plate to absorb vibration and no problems sense!

A problem running on one cylinder is almost certainly not the Boyer

Logical and is written as well in the Boyer troubleshooting blub, but a failing earth parth back to the battery will for some unknown reason cause one cylinder to misfire. I cured my similar symptoms by running a battery earth strip from head to the boyer red wire and then a decicated earth back to the battery. No idea why it works but it fixed mine and at least 2 other misfiring boyers.

The well known problem of the Boyer pickup coil wire fracture will definitely cause the the Norton to run on one cylinder. Usually, it will fire both cylinders once it's above 2500-3000 rpm range.

possibly fixed !

well rather than take off the carbs again i went for electrical problem
found a few things,poor crimp connector to supply of the Boyer.losing .5v accross it
also took the kill switch apart and found the wire had partially broken , again losing a little bit of voltage back to the boyer

main problem looks like the ignition switch , its def intermittent on the 1st click causing no spark at all , ok on the 2nd click
but its also causing the supply voltage to the kill switch and again to the boyer to drop 1v
strange thing is its ok until you kick over then the volts drop off by the 1 v then if you press the kill switch they come back up , probably due to the coils current draw i would guess
so ive ordered a new ignition complete with keys
fixed the wire in the kill switch
replaced the connector

part arrives next week i will keep you posted

Boyer is a fine system for pre 75 bikes ,they like a good strong ground so clean that up from oxidation-corrosion with a little die-electric grease too. Battery must be strong too. New micro models detect lowbattery to keep on firing ,yet only reliably fire on kickover /running unlike previous models that fire to on-off switching ! Seems you have 35 yr. old wiring connector probs. , recommend crimping then re-soldering all with new connectors.

I don't see what you are riding year or model wise however,
the ign sw can easily be repaired electric contact wise if you are so inclined as long as it undamaged from accident impact etc.
There is nothing magical inside. Just a little cleaning and some lube in the right place is most likely all that is needed.
The connector end of the case is peened over in 4 places. Just undo these carefully, disassemble, clean, assemble and peen it over again.
Your original ign sw, if it is, will have a date code on the side close but prior to the bike build date, this is important to purists.
My ride would die everytime I stopped then start again after various periods of button pushing and kicking.
This all started on the first day I took it into work after the purchase.
It died 4 times and I was around 2 hours late from a normal 20 minute trip.
One of my workmates was kind enough to follow me home with his pickup at days end, just in case, but you know it never misbehaved on that trip. The next morning at the very first stop sign it died again, this time I noticed the red ign light did not illuminate so I wiggled the key off and back on and then it did. My first clue.
The key jiggle bit worked everytime so that was that. I cleaned the internal contacts up and away we go.
I knew nothing about the Boyer, what had precipitated the points replacement in the fist place? I dunno.
You may find more reasons to ditch yours once the motorobike is otherwise sorted. The early units seem to be greatly affected in a negative manner by lower battery voltage. Bruises on the bottom of your right foot and may demand you make the move.

If it is an original switch I'd suggest just replacing it because they do plain and simple wear out and cleaning them could lead to having the same issues. I cleaned my original switch several times and it never was as good as a new replacement. The emgo replacements are fine and cheap enough.