She pops but will not start...

SierrasCafe530 · Feb 3, 2012

Hey all...

I have a 73 850 Commando. I just put in a Boyer Electronic Ignition. I'm getting a healthy spark and she's acting like she wants to kick. I'm getting pops and bangs, a little smoke and a lot of rust dust from the muffler. She's been sitting for almost 30 years. I have rebuilt the carbs, put in the EI, rebuilt the clutch pack, put in a new throttle cable, removed and cleaned the oil tank and lines and a lot more. Any ideas why she's not firing. I'm starting to lose my patience and my foot, leg, and back are killing me because of all the effort put into the kick start. Please help!

Hortons Norton · Feb 3, 2012

Be sure you have a fully charged battery, And then recheck your install of the ignition. If the battery is low the ignition won't want to fire at the right time. Good luck you'll get it. Chuck.

Brooking 850 · Feb 3, 2012

have you checked the static timing tosee if it is close to correct before you try and set the ignition s final position?
Did you carry out a compression test as after sitting for 30 years it may well have damaged/bore rings!!!
What about tappet settings as well, did you check those before trying to start as well?
Regards Mike

SierrasCafe530 · Feb 3, 2012

Has a new battery. Compression seems good. I set the timing as specified in the instructions for the EI. Not 100% if I did it right though. I don't know what tappet setting is?

Brooking 850 · Feb 3, 2012

The nick name tappet is used commonly for the gap between the end of the valves and the threaded adjuster with a lock nut off the rocker arm that is used to open the valves
Regardxs mike

Hobot · Feb 3, 2012

Oh ugh, when my past Boyer black beauty has done that and battery was fine I'd usually find I'd switched trigger leads sequence on assembly. If too advanced will back fire, if starts too advanced pipes will turn cherry red in seconds and if too retarded makes couging wheezes to start and if runs very suggish to throttle. Its possible there's fouling of magnets or coil poles on back side, ugh, damhik. But would it help to know most are able to get their Boyers spot on 1st time every time : ) I usually did. But just as often knocked something else loose to fool me it was even Boyer related, ugh.

swooshdave · Feb 3, 2012

Not kicking enough. :mrgreen:

rx7171 · Feb 3, 2012

SierrasCafe530 said:
Hey all...

I have a 73 850 Commando. I just put in a Boyer Electronic Ignition. I'm getting a healthy spark and she's acting like she wants to kick. I'm getting pops and bangs, a little smoke and a lot of rust dust from the muffler. She's been sitting for almost 30 years. I have rebuilt the carbs, put in the EI, rebuilt the clutch pack, put in a new throttle cable, removed and cleaned the oil tank and lines and a lot more. Any ideas why she's not firing. I'm starting to lose my patience and my foot, leg, and back are killing me because of all the effort put into the kick start. Please help!

The pops and the blowing of rust from the silencer plus you don't say its kicking back at your foot sounds to me you may have a grossly retarded spark.
Any chance you don't have the choke functioning since that can make a cold one hard to start.
After a lot of kicking I'd check plugs. If wet the choke would be working but if dry then choke not.

marinecommando · Feb 3, 2012

Are you using the correct mark on the rotor? There are 2marks on there. Check TDC and note which mark corresponds, then mark it.

MexicoMike · Feb 4, 2012

My money is on incorrect timing. That's a classic symptom. Keep in mind that Boyer's are notorious for timing errors with low voltage. I realize you said the battery is fine but are all the connections fine as well? You can have a good battery but low voltage due to corroded connections, bad grounds, etc.

But the first thing to do IMO is to recheck the static timing.

The second thing I'd do is get rid of the Boyer.

DogT · Feb 4, 2012

Check the voltage across the ignition switch. A 30 year old switch is probably going to be iffy. Or you could just hot wire it.

Dave
69S

pete.v · Feb 4, 2012

Nudge the pick up a little in one direction and see if it goes or improves. If not, go the otherway. Not to much at a time, you don't want to over advance it or your pipes will blue up before your get the timing light in place.

Ok, I'll go there.
Are the plugs wet? If not, with the air cleaner off (of course) lift the slides and squirt a little fuel down the manifolds.

And, If it isn't starting after a half a dozen kick, stop and access. Don't needlessly stress the gearbox as some may incourage. :mrgreen:

grandpaul · Feb 4, 2012

I'll bet Hobot has it - the trigger wires (black/yellow & black/white) are reversed.

SierrasCafe530 · Feb 4, 2012

marinecommando said:
Are you using the correct mark on the rotor? There are 2marks on there. Check TDC and note which mark corresponds, then mark it.

There are two marks with red paint on them. I was guessing it was the big marker. My husband just tried it with the other marker. Still no life... We are out of ideas.

SierrasCafe530 · Feb 4, 2012

grandpaul said:
I'll bet Hobot has it - the trigger wires (black/yellow & black/white) are reversed.

No there not. I may be a girl, but I got that part right. :wink:

SierrasCafe530 · Feb 4, 2012

pvisseriii said:
Nudge the pick up a little in one direction and see if it goes or improves. If not, go the otherway. Not to much at a time, you don't want to over advance it or your pipes will blue up before your get the timing light in place.

Ok, I'll go there.
Are the plugs wet? If not, with the air cleaner off (of course) lift the slides and squirt a little fuel down the manifolds.

And, If it isn't starting after a half a dozen kick, stop and access. Don't needlessly stress the gearbox as some may incourage. :mrgreen:

The plugs are wet and a black. The spark seems to be a little weaker today. Could it be that my coils are crap?

1up3down · Feb 4, 2012

Ok, this may by an insultingly dumb question to be forgiven if already considered but:

You say the plugs are wet and black and she pops but will not start

Have you now thrown those plugs away and installed new fresh plugs?

No bike will start with fouled plugs.

bwolfie · Feb 4, 2012

I agree, vhange the plugs, they are cheap.

Also how good is the battery, it may read over 12 volts, but as soon as any load is pulled it could go south quickly.

I would hook up a volt meter and monitor the battery while you try to start the bike. Boyers are voltge sensitive.

I have an AGM battery that is less than a year old, shows 13 volts, but goes down to 6 volts as soon as any power is drawn.

303 fmj · Feb 4, 2012

Nothing mentioned as to which ignition coils are installed---their connections---and---their condition--crushed sides, rust in the towers--and which spark plug wires
are being used. Was original system points/condensor? Were ignition coils original Lucas or ?

rpatton · Feb 4, 2012

I had the same thing happen when I put an analog Boyer on my bike. Somebody on the NOC list said it could be interference from the HT leads. I moved the Boyer to a chair next to the bike and it started right up. I've since then have always used a shielded pair of leads from the pickups to the box.

She pops but will not start...

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