Help (I jinxed myself)

I was just bragging to a friend about how "reliable" my Commando is and how it starts 2 kick nearly every time.

Now "Ethyl" won't start. What have I done to her?
(besides the sarcasm which I am sure she understands
and punishes me for, much like my wife,
who won't start occasionally either)

Here's my game plan - thoughts and help appreciated.

1. check the battery voltage

2. check for spark

3. check for fuel at the spark plug

4. fix the timing (this is what I suspect is the culprit)

What have I missed? Thanks in adance.

9 times out of 10. No spark! Check coil wires!

Itz dah kill switch!

I agree with Bob, 9 out of 10 it will be spark.

Have you got a kill switch? good place to start. If you were boasting too much maybe a little bird just.......

Unless you have a good reason to think it may be at fault DON'T play with the timing yet, this may bring in a whole set of other problems,

First thing, just look over all the wiring, could be as simple as that as Bob suggested,

Pull out the plugs, hook them back up again & kick it over( even if it is a MK111), this will you good voltage and if there is spark there it will show up.

You wouldn't have points still? that will be a whole different approach if you do. If it is electronic ignition it will want good voltage, measure the voltage across the battery, 12.5 is perfect, 11 will start to be a problem. Got a battery charger? Hook it up and kick it over again. ( Unless you have some ultra modern computor controlled ignition/ injection system) That will overcome a slightly flat or faulty battery.. it never hurts to put in new plugs at this stage.

If you have good voltage and no spark try to measure the voltage at the coils( l don't have to mention to turn on the ignition switch?) See how this goes, l'm on night shift for the next 2 nights so will be happy to continue the hunt.... Groges

I charged the battery overnight and tried again - no luck.
I had checked battery voltage prior to this.
It had been 12.3 V two days before but have not had time to check since.

I will check wires and spark using new plugs this weekend, although I hadn't even thought of a coil wire.

I don't think its the kill switch b/c I rebuilt/cleaned it last season but it is also an easy check - thanks.

I'm ashamed to say I don't even know if it still has points but I don't think so - another thing to look into.

Nothing is foolproof to the sufficiently talented fool

Hi
It must be the season, my Mk111 ES decided to do a similar thing just before a run, after much fiddling with carbies, resistors and cables, I replaced the points with electronics, now it sparks on kick,
but not on ES.
The next step is to replace the coils and HT leads?
Chili

Chili said:

I replaced the points with electronics, now it sparks on kick, but not on ES.

Click to expand...

Have you disconnected the white/purple [WP] ballast resistor bypass wiring from the coils and starter solenoid?

If not, then the electronic ignition won't fire when the stater motor is operating.

The white purple wire had been disconnected from the ballast and the coils but not the solenoid, done now, after reading other post am thinking about the battery.
I am starting to think my 66yr old mechanical fingers are turning into very passionate fingers.

Hi roqueweiler,
just after midnight here so l have a bit of time to play " start the beast", if l'm telling Grandmother how to suck eggs just let me know....

The 12.3 voltage is fine, this will power even electronic ignition, however there may still be battery problems but we will work through this,

A couple of things will change how we go about it, is your bike a MK111 with electric start? and /or has it got electronic ignition and hence what type.

Step 1, do we have spikensparkin'?

Either way, pull the plugs out, grab new ones, hook them up to the leads and then fix (cable ties are great! ) (is that an australian colocalism?) them to the engine so the metal part is nicely earthed. On with the ignition and kick it over ( no starter at this stage) all the while checking for spark. A nice blue flame is best, red orange maybe. None, we are on step 2.

Step 2, No Sparkin.

Nows the time we look for points or electronics

A, Points.

this is actually the easiest to fix, but EI is the better system in the long run,

Pull of the ignition cover, (if it is a fat one like the photo of L.A.Bs bike it is EI, and the flat roundish cover on rvichs bike is most likely points)
While watching the





P

Grogan said:

Hi roqueweiler,
just after midnight here so l have a bit of time to play " start the beast", if l'm telling Grandmother how to suck eggs just let me know....

Click to expand...

Only three posts and you throw down a memorable quote. Sweet. :mrgreen:

gap in the points. Are they opening? As the lob comes round the points should open to 12 thou or so( 3 thickness' of copying paper if you need a guide) if they do not, here is our problem.
Solution, pull them out, ( do it on the high point of the cam) either get news ones, clean the old ones( the ladies nail file is great for this, or fine wet and dry emery paper) put them back in and set them to 12 thou ( better look this up in the manual it has been years since l have had to set points.) on the high lobe point.

Do the kick over test again and see how we go. still no spark? Go to three.

Step 3 start here if the bike has EI.

Grab your Multi meter, on with the inition switch and measure the voltage at the coils. The positive side of the coil ( the 12V power side) is the white wire l think. (better check that on the wiring diagam, but l think Norton use BS wiring code)
Now, no voltage? start going through the wiring and switches.

Let me know how we go with all this if we have no luck we will go to step 4.....and beyond.
Groges.

Thanks Swooshdave, nice to be welcomed,

l like Matt's advise, l wonder if Rockweiler has hills round his place!

Your bike looks impressive, is it a Dunstall set up.

When l get home l'll try to set up a photo or 2
Groges.

Grogan said:

Step 3 start here if the bike has EI.

Grab your Multi meter, on with the inition switch and measure the voltage at the coils. The positive side of the coil ( the 12V power side) is the white wire l think. (better check that on the wiring diagam, but l think Norton use BS wiring code)
Now, no voltage? start going through the wiring and switches.

Click to expand...

Unless a Commando has had its electrical system polarity changed from normal positive earth/ground to negative, then:

1.White is negative (power supply from ignition sw.).
2. If normal positive earth, then power is not supplied directly to the coils with any currently available Commando EI ignition (Boyer, Pazon, Tri-Spark, Sparx, Power Arc etc) as far as I'm aware?
3. If 1971-on Commando, then the white does not go to the coils, therefore unless the kill switch has been bypassed, the amplifier box negative wire (usually either a white, black or black/yellow wire) would normally be connected to either the white/yellow or white/blue wire.

Hi L.A.B'
you're right, l'm not at home so hav'nt got access to my wiring diagrams but l changed my bike to negative earth in the 70's so l could use off the self and triumph components, especially alterator diode packs/voltage regulators, l seem to remember Norton ones costing half a weeks pay and regularly.

The white wire is power and the place to check it is at the power supply into the EI (if it is fitted.) lt doesn't matter too much which way round it is measured the meter will just read negitive voltage if the meter probes are back to front.

l had a number of different ignition systems with the first being a home assembled kit one that measured 4x4x2" in its box, difficult to mount neatly on the bike! This came from " Dick Smith" electronics hobby shops and was for cars with points ignition. It was a spark "amplifer" system and relied on the original advance/ retard system and the points for the trigger. Worked well enough and the points never wore out because they took no current but it didn't look "cool".

The system l had when the commando was retired was off an 1980s Bonnie, but this still had mechanical advance/ retard, on this restoration l will go for some sort of 2000's EI.
regards Groges.

Ta!
The EI is TRI-SPARK, and the wiring goes like the song,( white-yellow to black-yellow into EI black-white to -coil 1 then + coil 1 to -coil 2 then +coil 2 to earth).
The kick produces only poor white spark, am now going to try it with a car battery semi-wired in.
thanks for the HELP.

The Passion fingers report.
Car battery useless. after hot wiring from the negative to the yellow-black. it started, removing said wire it ran if not perfect but lumpily, now at least the Canadian light system
works properly, ie, the headlight does not come on till the engine is running, as before draining the battery.
thanks for all the suggestions.
chili

Hello,
u are correct with checking for spark and then fuel. This can be done quickly and will identify if u have a problem with either system. Once set... your timing should remain unchanged and no further adjustment required. This should be ok. Knowing your ignition is a must so check and see what your running with....points or electronic. This makes a big difference when trouble shooting electrical issues related to your ignition. First checks: spark and fuel then work it from there. keep the post active and let us know what u come up with. are u getting spark? are u getting fuel?
Dox

hello Dox
Just wondering do you know The Doxford Engine Song, with movements? on to the real message have just installed TRI-SPARK EI,
spark weak white, also thinking 98 unleaded petrol, might be to much.
chili (an old Doxford engineer)

Chili said:

hello Dox
Just wondering do you know The Doxford Engine Song, with movements? on to the real message have just installed TRI-SPARK EI,
spark weak white, also thinking 98 unleaded petrol, might be to much.
chili (an old Doxford engineer)

Click to expand...

Hi,
I don't know the song but have worked on the doxford engine for an extensive period of time {8} years. It was the main power plant on a ship I worked on. 4cyl 8800 hp. one of only two left in the world a relic.
Dox

Chili said:

on to the real message have just installed TRI-SPARK EI,
spark weak white, also thinking 98 unleaded petrol, might be to much.

Click to expand...

My Commando's Tri-Spark produces strong blue sparks, in fact they're probably the strongest sparks I've ever seen from an aftermarket ignition system. My MkIII also starts very easily on the button. High octane rating is unlikely to be the problem I would think.