Crankcase oil, spark plugs, and why won't this contraption start?

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Hey folks. I'm working on getting a 1973 Commando restarted after a long time sitting. I changed the oil using the instructions from an old 2005 post here. That post noted removing oil from the crankcase. I've heard elsewhere that the oil in the crankcase is differently. Does the regular oil reservoir serve oil to the crankcase or do I need to fill the oil in there separately? If separate, can anyone fill me in on the best weight?

Also, I'm replacing the old plugs. The old ones are model NGK BP7ES which has been retired but has a .9mm gap. Other recommendations I see suggest a .7mm or .8mm gap. Any recommendations on the best modern NGK replacement for this old spark plug?

Finally.. after changing the oil I tried starting the bike and after nearly throwing my hip out kicking it over for 30 minutes, it caught on for a few seconds and dumped oil on the ground out the puke hose. My best guess is that it was wet sumped. I let the oil drain out the oil overflow hose, and then siphoned more oil out of the reservoir to lower the overall oil level. Here's the thing.. I can't get it to start again since that brief start for 20 glorious seconds. Any idea what my problem is? I'm "tickling" my dual Amal carbs with four presses on each side. I give it a small turn of the throttle and kick like hell to turn it over. I can't get it to start again. I charged up the old battery with the correct lithium charger for the battery. Current gas mix is about 20% sea foam and 80% petrol (in case there was gunk in the carbs). I would love any ideas on anything I'm missing!

Thank you!
Mike
 
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You press the tickler until the fuel spurts out, 4 presses will get you nowhere and just wear the plunger out.
 
You press the tickler until the fuel spurts out, 4 presses will get you nowhere and just wear the plunger out.
Thanks. I was trying that too by the end of the night but afraid of flooding it so this really helps. I may have not been supplying enough fuel.

Side note.. The previous owner removed the choke.. Which is interesting. So It's about 55 degrees F here today. I have a heater directed at the engine to warm it up..
 
Flooding is required. You press the plunger until fuel comes out. It's not like the primer bulb on a lawn mower.
BPR7ES is the replacement. Or Champion N7YC if you can find them.
 
1.Drain oil from sump(large plug under engine)
2.Make sure the oil tank is at correct level.
3.Remove air mixture screws and run small wire thru pilot jet. Spray cleaner thru passages on carb.
4. Kick and start

Not details here but you can search if you don't understand.
 
That post noted removing oil from the crankcase. I've heard elsewhere that the oil in the crankcase is differently. Does the regular oil reservoir serve oil to the crankcase or do I need to fill the oil in there separately? If separate, can anyone fill me in on the best weight?

It's a dry sump engine, so the oil that is pumped to the crankshaft and valve gear drains to the sump where the scavenge side then pumps the oil back to the oil tank so it's the same oil.
The sump should be filled with approximately 300cc of engine oil so the cam lobes and followers will be splash lubricated immediately the engine starts up.
 
1 to 2 ounces per gallon.
I did a high concentration in a small amount of overall mixture to soak the tank and carbs overnight, then I diluted it to 80/20. Do you think I ought to dilute it back to the recommended 2 oz per gallon by adding more gas so it will start properly? I was thinking of just burning off the sea foam/petrol mixture and then switching to straight petrol.
 
I did a high concentration in a small amount of overall mixture to soak the tank and carbs overnight, then I diluted it to 80/20. Do you think I ought to dilute it back to the recommended 2 oz per gallon by adding more gas so it will start properly? I was thinking of just burning off the sea foam/petrol mixture and then switching to straight petrol.
You need to take the pilot air adjusting screws out and clear the pilot bush with a piece of wire or 16thou twist drill etc
The jets get clogged through standing and no amount of carb cleaner will clear it
 
I've never used Sea Foam so I don't know what effect such a high concentration has on combustion so it might be a good idea to drain the tank and carbs and try some fresh fuel without the Sea Foam at least until you get the engine started.
 
You need to take the pilot air adjusting screws out and clear the pilot bush with a piece of wire or 16thou twist drill etc
The jets get clogged through standing and no amount of carb cleaner will clear it
Thank you! From the diagrams I found it appears that the pilot air adjusting screws are the ones right under the tickler. Does that sound right?

How delicate do I need to be when poking in there with a wire to clean it? I'm thinking of using a bare16 gauge electric wire to do the cleaning, does that sound reasonable?
 
How delicate do I need to be when poking in there with a wire to clean it? I'm thinking of using a bare16 gauge electric wire to do the cleaning, does that sound reasonable?

Yes, just take care not to enlarge the jet (seen in the image on the right with the pilot air screw removed).
Crankcase oil, spark plugs, and why won't this contraption start?
 
Check compression and make sure you have spark at the plugs. Then starting fluid special sauce. That should catch it enough to blow the cobwebs out

Good luck :)
 
Everything everyone has said is good. Here's what to do to make it start - probably won't idle - once starting reliably work on the pilot circuit so it will idle.

1) Drain the oil from the sump.
2) Drain the tank, both sides, and put in fresh hi-test with or without ethanol. No additives.
3) Drain the float bowls
4) Make sure you have good plugs Champion N3 or N4 NGK B7ES or B78S (an "R" in the number is good if you have electronic ignition but it will start with or without the "R", with or without "P" doesn't matter). They come gapped well enough.
5) Make sure you have spark.
6) Make sure the choke, if equipped is OFF (turned all the way tight, not loose)
7) Tickle both carbs until you see gas
8) DO NOT touch the throttle!
9) Kick - if nothing has happened after three kicks, call me, you'll be at it forever trying to figure it out here message by message 703-200-4025
 
If you have drained the sump and you have got compression, spark and fuel - it should fire up . If it does not, replace the spark plugs with new ones. You are the boss, don't cop any shit.
 
Everything everyone has said is good. Here's what to do to make it start - probably won't idle - once starting reliably work on the pilot circuit so it will idle.

1) Drain the oil from the sump.
2) Drain the tank, both sides, and put in fresh hi-test with or without ethanol. No additives.
3) Drain the float bowls
4) Make sure you have good plugs Champion N3 or N4 NGK B7ES or B78S (an "R" in the number is good if you have electronic ignition but it will start with or without the "R", with or without "P" doesn't matter). They come gapped well enough.
5) Make sure you have spark.
6) Make sure the choke, if equipped is OFF (turned all the way tight, not loose)
7) Tickle both carbs until you see gas
8) DO NOT touch the throttle!
9) Kick - if nothing has happened after three kicks, call me, you'll be at it forever trying to figure it out here message by message 703-200-4025
Question about the choke.. A previous owner removed the choke and it's nowhere to be found. From what you said about keeping it off, I wonder if I should bother replacing it? The PO seems to have known what they were doing, but lived in warm weather..

Thanks for all the advice and even offering to be there for a call! I got it going and took my first ride on a Norton today. It felt really solid so against my better judgment for a "new-to-me" bike of somewhat unknown inner condition, I revved out the gears and had an absolute blast. I can't believe the torque. For a bike of this vintage I've never ridden something so powerful. It just feels good.

Next I'll need to dial in the idle. This bike has lived in warm weather at sea level (nice life). I am at altitude with a chill on many days. Also need to sort the brakes. It took quite a bit of lead time to stop it..
 
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