Advice please-RHS cylinder dead

So my bike has been sat up unstarted since my knee service on 30 October last year. Am bating to get up and going so have been tinkering away. Fitted the flat slides etcetera. After some initial trouble I have eliminated the flooding/float needle issue and have moved onto tuning.
Have them sync'd as best I can with coat hanger wire and have got the bike to idle tuned.
Road test is a different problem. Seems under load the RHS cylinder just totally drops out and I mean no firing at all. Turns into a 414 single. It is important to note that revving (on stand not under load) is or was fine prior to road testing.
Soon as load is applied, nothing on the RHS.
Checked battery and it's now in the charger having measured at 11v. Pulled pints cover and checked connection on the Boyer (they are soldered and appeared fine).
Pulled plugs prior to tuning idle to check for spark and had spark. Strong on the left but maybe not quite so on the RHS.
This was a daily rider prior to my op so am a bit stumped really. I thought Boyer would still fire off 11v but will eliminate that through battery charge.
Is it possible that my RHS coil has crapped itself through not being used? Seems to me to be the suspect. I have two older coils here but don't know how to test if they are ok.
If I get an ohm meter(which I have no idea how to use really) and stab one pointy thing in the plug lead hole and the other pointy thing on one of the poles I get 9.1 and 5.3 from them. The 9.1 coil is 6v emgo and the 5.3 is old Lucas. Measurement across +&- poles gives 0 on both.
Back to the bike, can't get any ignition now. Coils are 6v in in series.
Haven't measured the ohms of the fitted coils.

Any advice would be appreciated

Sounds like a coil or even a plug wire. How old are they? I went through a similar experience with my 85' Westy. Problem only resolved itself with new plug wires.

11v is awful low voltage.

See how it goes all charged up, we could be guessing here forever unless that is good.

I agree that 11v is too low. However the exact same thing happened when one of my plug wires started to go south. Missed under load but fine when revved in neutral.

I'm thinking of maybe getting a dual coil setup. I usually bin old plug leads when I change them out. If I don't have a spare then I'll swap sides to see if the issue moves to lhs.
Just got me a bit stumped really.
How do you tell if the coil is ok or not?

Battery is on charge. 11v is just residual charge but I thought boyers would still work a bit lower than that before an ignition issue would present itself.
Either way it should be resolved as a battery issue shortly.
Plug leads aren't that old, maybe 18months max. If I can work out haw to bench test a coil and identify that as the issue then I will probably look into a 12v dual coil that comes with leads incorporated into the coil pack

Try a single Harley coil. Conversion available from CNW. Comes with a bracket etc. Good strong spark. I run a 40 thou gap with TriSpark ignition.

The Boyer fires both coils at same time an uses the wasted spark idea. So swap coils over an see if problem moves with it. If it doesn't try HT leads then plugs.
You could upgrade but the standard stuff works so you could replace the faulty part. If you are lucky it will be a bad connection but sound like a coil has failed as both coils should be giving similar ohm readings.

Tell us more about "fitted flat slides etcetera"
If it was running fine, then you changed some things, now it's not, troubleshoot 101 dictates to revisit the changes with scrutiny, and possible accidental changes (jostled wire while fitting cables for instance). New carbs? Used? Check the fuel and air passages for possible debris. Does putting on the choke while in situ help?

You can not verify that the Boyer pickup wires are good by visual inspection. They fracture inside the insulation near the soldered point on the board. You definitely need to do a continuity test to verify they are indeed not the problem. The fact that the Boyer has a wasted spark will NOT keep both cylinders firing if one pickup wire is fractured.

Did you try a fresh spark plug in the RHS?
Just because it's sparking outside the engine doesn't mean it's providing solid spark under load.
All the farting around with new carbs may have diminished it's ability to fire.
Probably not the culprit but it's easy + cheap enought to try. Just a thought.

Also you mention you fitted flat slide carbs.
Any chance the RH enrichener button is not fully seated "off"?

concours said:

Tell us more about "fitted flat slides etcetera"
If it was running fine, then you changed some things, now it's not, troubleshoot 101 dictates to revisit the changes with scrutiny, and possible accidental changes (jostled wire while fitting cables for instance). New carbs? Used? Check the fuel and air passages for possible debris. Does putting on the choke while in situ help?

Click to expand...

I had been on some strong meds but about 3-4 weeks after my op I kicked over and I seem to remember a misfire on rh cyl. This was when the single mik was still in situ but I can't be 100% positive. I thought at the time it was probably just a fouled plug from wetsumping.
I've tried using the enrichen circuit to see what happens and all the usual suspects regarding carb fitment. I just have a strong sense that this is cleared as the issue; albeit after I had to resolve some float issues.

Still on the mend so have limited ability to keep kicking but today is a new day so will try eliminate the coils, leads and plugs. Btw started with fresh auto lite plugs and have since fitted second set. They showed clear signs of running far to rich but that was prior to idle tuning with gunson color tune for base setting.

So I've just taken a giant leap toward a solution burnt electrical knowledge ain't the best.
I've identified the RHS plug will not spark when earthed to the head. Lhs will. Having swapped leads around etcetera I still wasn't getting spark when the plug is touching the head. If I hold it away from the head I get good spark and good shock ( up to the first knuckle). I will rip the tank off and carefully inspect the wiring between the two coils just to be sure (ie all poles on the coil pack to their terminus)
Any tips what could be causing this?

Old Britt's has a really nice Boyer Troubleshooting Guide on the web site:
https://www.oldbritts.com/boyer_testing.html

Specifically this test:
Take both spark plugs out and ground them on the engine. Turn on the ignition and depress the kill button. this will collapse the field on the coils and you should get a spark on both plugs.

Cheers for the tip re Boyer troubleshoot.
Swapped the coil out and used an old Lucas coil I had. I get spark now when the plug is earthed to the head.
The coil I removed was crimped as in squashed to create a seam along the top. I'm thinking that the windings inside may have earthed to the casing of the coil thus sending current through to the plug when not grounded. When grounded to the head it was just bi passing and earthing directly to the frame.
Again, I openly admit that I am lost with electrics.
On my way to physio so when I get back I will pull both plugs again to confirm spark when grounded to head on both sides, then refit the tank and see how we go.

You seem to be doing pretty good for someone "lost". You got it! The crunching of the coil body over the years is pretty common.

Cheers batrider
Trouble is that RHS is sparking nicely but lhs now weak as. In the dark, the lhs still sparks but only just, almost a light orange but the RHS is now nice and strong. Weird.
All I did was check the wiring, swap out crappy coil and refit the tank.

Will this work with my Boyer mk111?
4.3ohm dual fire
http://pages.ebay.com/link/?nav=item.vi ... 1536575801

Cheers snorton
I had issues as my spark problem shifted to the lh cyl when I fitted the other coil so I'm binning the lot and will fit an Andrews 4.8 dual fire Harley coil to totally eliminate any coil or coil connection issues.