Kick starting the 850 bastard. [ nothing to do with iso's and other shit ]

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Just got back from another NZ rally. Bike went well. Averaged 62 mpg imperial over the whole trip. Sometimes down to 54 mpg and best was 72 mpg. Only trouble, after its done 1000 kms or more it becomes hard to start [ actually it wont ]. It has done for a few years now and its become obvious it must be the shit unleaded fuel we have to put up with in NZ. [ i am only guessing here ] Plugs turn black. I am using N9yc or BP6ey, but still a problem. New plugs and it starts first kick, which it did before going on the trip and which it did every time I stopped overnight or for fuel, until I got to Wellington. Luckily I was staying on a hill so crash started in top gear. When got to the ferry terminal, I changed to the NGK plugs. Bike started first kick most of the time from then on.
I did break the side stand bolt when I got off in Turangi to stay the night. Another mod coming up but thats another story.

Does anyone else have this starting issue.
 
Indeed I do, but mostly is just my age and strength. My grandson only has to look at the kickstart and it'll fire up.
Is the motor burning oil? if so that might be the cause of the premature plug failure.
 
Not on the Commando, but 2 other Nortons, used to chew through NGK BPR8ES like nothing.
Spoke to NGK technical - no help there.
Changed to iridium (BPR8EIX) and never a problem since,
Like the thread title BTW - 🤣 🤣 🤣
 
Just got back from another NZ rally. Bike went well. Averaged 62 mpg imperial over the whole trip. Sometimes down to 54 mpg and best was 72 mpg. Only trouble, after its done 1000 kms or more it becomes hard to start [ actually it wont ]. It has done for a few years now and its become obvious it must be the shit unleaded fuel we have to put up with in NZ. [ i am only guessing here ] Plugs turn black. I am using N9yc or BP6ey, but still a problem. New plugs and it starts first kick, which it did before going on the trip and which it did every time I stopped overnight or for fuel, until I got to Wellington. Luckily I was staying on a hill so crash started in top gear. When got to the ferry terminal, I changed to the NGK plugs. Bike started first kick most of the time from then on.
I did break the side stand bolt when I got off in Turangi to stay the night. Another mod coming up but thats another story.

Does anyone else have this starting issue.
Sounds like it’s rich and is consequently fouling the plugs to me.
 
Head re-torque, tappet adjustment, clean out the oil drain in the head and clear pilot jet: one (or more) of those 4 sorted a similar issue for me.

Edit: I adjusted the pilot air screw once all back together, might have been that, too.
 
I'd be curious what the plugs look like after 500 km. Stark raving white, normal tan, oily black, etc. ? It is hard to imagine that you have had several sets of marginal plugs that pooped out after 1000 km. Does the bike use more than a pint of oil in 1000 km ?
 
NGK's locally have turned out to be crap' for both Norton and Skidoo. Life expectancy 2 short rides.
Found that Chinese knockoffs were prevalent and the plugs I had matched imperfections mentioned on a few forums.
Switched to Champions & problems gone on both units. (Not something I ever would have said a few years ago. )
Cheers
 
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Not on the Commando, but 2 other Nortons, used to chew through NGK BPR8ES like nothing.
Spoke to NGK technical - no help there.
Changed to iridium (BPR8EIX) and never a problem since,
Like the thread title BTW - 🤣 🤣 🤣
Likewise, use Iridium's on all my bikes and never an issue.
 
Back in the early days Champion plugs went through a bad batch of plugs and for a few years they got a bad reputation but they came back but people just never got over that bad reputation at the time I went through using NGKs and other brand plugs but my Norton just didn't like them but Champion came good and my Norton runs so well with the N7YC plugs and now running the Joe Hunt I have got such long life out of my N7YC plugs.
 
In answer to the oil question, I covered 1315 miles and used just under 1 lire of oil. The plugs don't show signs of oil burning though. Would a Commando that does between 54 mpg at worst when pushed at 70 mph in a head wind , and 72 mpg cruising be running rich? The plugs look quite dry grey/black when they come out and the coating is very thin. It comes off relatively easily when san blasted. I used to be able to tell when a car was burning some oil by seeing heavy dry brownish carbon deposits on the plugs.

BPR8EIX didn't last nearly as long so threw them aside. @ 4 time the cost, they were not worth it.

It doesn't seem to matter whether I use 7YC. 9YC, 6ES or 6EY, all have roughly the same result.

I am running with a standard Pazon set at the manufacturers specs.
 
Not on the Commando, but 2 other Nortons, used to chew through NGK BPR8ES like nothing.
Spoke to NGK technical - no help there.
Changed to iridium (BPR8EIX) and never a problem since,
Like the thread title BTW - 🤣 🤣 🤣
I would have thought 8ES would have been a little too cold as the recommended heat range is 7ES. I've found with modern petrol 6ES NGK or 8YC Champion work really well.
 
I would have thought 8ES would have been a little too cold as the recommended heat range is 7ES. I've found with modern petrol 6ES NGK or 8YC Champion work really well.
Yes - as I said that was not for the Commando - I run BPR7EIX in that
 
I copied and pasted BPR8EIX but I actually used BPR7EIX.

I have been using a high Zinc oil [ as talked about on this forum ] Penrite 20-60 for the last few years. I wonder if the zinc in the oil is forming an electrical connection between the electrodes on the plugs. I cant remember how long this hard starting has been going on but it hasn't been very long. For years I used Caltex 20-50 and had no problems, so maybe I should try that in my next oil change and see what happens. It would be nice to think the BPR7EIX might actually work. Still, I will always carry 4 spare plugs with me in case.

The plugs in the machine are N7Y at the moment and have been in since Turangi. When I chained the bike up down there, I also disconnected the power supply to my ignition, and in a senior moment the next morning when it would not start after 15 kicks, I changed the plugs. Kicked it twice and thought that was odd, then I looked realised what I had done. Reconnected and started first kick. That was a hot sweaty 10 minutes [ or more ], but I guess the anti theft idea worked.
 
Sounds too rich to me. Try dropping the needle and running thru the Amal tuning procedure again. Mark the throttle so you can clearly see a quarter of movement.
 
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I'd say particularly blocked pilot circuit
Pull taps off and check tank filters also...my 2 cents worth
I have seen a similar issue with another bastard 🤣
 
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I very much doubt you will need this stuff as we appreciate you are very competent with Nortons.
It may come in handy for some that aren't having no luck.
 

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You guys may have misunderstood my question. I can go a whole year and 1 kick starts the bike. When I go on a Norton rally that is over 1000 kms, I have to change the plugs to get it back to a one kick start.
How many Commandos can get 62 mpg let alone 72 mpg. To me, that means its not running rich. I spend quite a lot of time getting my commando economical, the the extent that I moved the needle seats up in the bowls to lower the float level. I then had to raise the main jet needle as it was slightly too lean. I do not have chokes on my bike, so I have to press the tickler till petrol shoes below the ticklers.

The reason for the question, is to find out if anyone else has had the same problem.

I don't normally have a starting problem, and the bike goes very well.

My carbs are old, and probably worn, but that doesn't to me explain why it starts first kick all year, then wont start after a 1000 to 1500 km run. Fitting clean plugs seems to solve the problem until I have done another 1000 km or so. The engine is still standard although I fitted new pistons and valves about 8-10 years ago. It does use some oil, but is not consistant. [ Drove from Wellington to Auckland on time and it didn't use oil. Might have been the time I stayed with you Dave ]
 
Sounds like oil combustion, just a enough to foul up on the extended runs and consume oil at rate you stated.

Have a good look at next long ride for any signs of smoke, esp at throttle blips. Sometimes can be hard to see depending on background and ambient lighting.
 
You seem to have ruled out wrong plugs.

And it sounds like you know your way around Amal’s.

As you’ll know, the different circuits are quite independent of each other to a degree.

Is it possible you have one circuit inadvertently rich, perhaps to compensate for your lean settings elsewhere, and that just happens to be where you spend more time on a run?

If not, it has to be oil burning.

AFAIK it’s only the burning of fuel or oil that can blacken and foul plugs…
 
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In answer to the oil question, I covered 1315 miles and used just under 1 lire of oil. The plugs don't show signs of oil burning though. Would a Commando that does between 54 mpg at worst when pushed at 70 mph in a head wind , and 72 mpg cruising be running rich? The plugs look quite dry grey/black when they come out and the coating is very thin. It comes off relatively easily when san blasted. I used to be able to tell when a car was burning some oil by seeing heavy dry brownish carbon deposits on the plugs.

Is the insulator as you describe on the fouled plugs? It should be white. Give us a pic.

You may have tuned your bike fine for local riding at mixed rpm’s, but long blasts of motorway level rpm’s may need some fine tuning. Again, plug pics may help vs oil combustion.
 
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