New Norton knocking help please

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Whooo... definitely a world of knowledge. Will set timing tomorrow morning and then pick up new plugs this weekend. When running...as said , timing should be 30 at 5k and my timing lite should be set at 0 on the dial. Hopefully my wife can hold it steady I will get some race gas and try to mix up a batch good gas and try that.
 
baz said:
Definitely check your timing and even then it won't hurt to back it off a tad as you don't know if the engine is standard compression
Is there any kickback when you start it?
If you still have problems after this you will need to know what throttle opening you are at when the pinking occurs
Marking the throttle drum will help with this
I once had high compression pistons and a combat head on my 750 I never did stop it pinking until I changed to std pistons
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A couple kick backs but probably due to kicker position...starts on 1-2 kicks.
 
Shitty fuel goes "POP". Good fuel burns and expands throughout the power stroke. Tetraethyl lead was an additive that inhibited fuel from going "POP" because it slowed down the flame front. That allows an engine to be advanced in it's ignition timing and not ping nor kick back when you go to start it. Todays ethanol fuel does go "POP" more than the fuels of old. Cars have knock sensors on them which essentially retards the ignition timing when the sensor detects the PING due to crappy fuel.

As was said, flame propogation speed of fuel is even more critical in higher compression engines... So, find a better fuel source and maybe retard the timing a few degrees. Certainly lowering the compression is an answer too, but that means taking the engine apart to add a spacer under the base gasket, so it's easier to just find high quality fuel and retard the ignition a bit.
 
Motown1 said:
A couple kick backs but probably due to kicker position...starts on 1-2 kicks.
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It should not kick back ... mark the points stator with a scribe and then pull timing back a couple of degrees. If you use a pencil then move the marks on the stator and timing cover out of alignment that should be enough..for an experiment. If they kick back with a boyer then with standard 9to 1 that usually means 34to 36 which is way too much.
 
Don't do multiple things to "fix" this. Check/set the timing at the factory setting and re test. DON"T do anything else until you have done that and then only if that didn't fix the problem.

If the engine is stock and the ignition system advance its correctly set and working properly, it will have no issues at all running on commonly available fuel at any gas station. No additives, aviation gas, non-leaded fuel, etc are necessary. ;)
 
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oldmikew said:
It should not kick back ... mark the points stator with a scribe and then pull timing back a couple of degrees. If you use a pencil then move the marks on the stator and timing cover out of alignment that should be enough..for an experiment. If they kick back with a boyer then with standard 9to 1 that usually means 34to 36 which is way too much.
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This.
Quickest, easiest “acid test”.
Then report back.
 
Motown1 said:
I did not look since I was head down listening...my bad...should have known better.
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I asked because it is not uncommon for riders to shift into higher gears too early; this proclivity is almost encouraged by the Commando's low end torque characteristics. BMW airhead pilots are famous for being in high gear before they exit their driveways and often resort to twin plug ignition systems to address the pre-ignition (knock/ping) that results from too much engine load at too low an RPM.

You have mentioned that down shifting solves, or diminishes, the knocking. So, if your ignition timing is correct, I'd suggest that you try the same roads and use the lower gears to keep engine RPM above 3500 and see if this eliminates the issue.

Best.
 
Well I did not get a chance to check timing today...other issues. I will check tomorrow. On the Boyer plate, which direction is retard/advance?

I understand the 30*@ 5000 grand...what about idle? And this Amal 34mkii....where is the bloody idle screw? I’m not trying to be dumb but all my Mikunis had separate engine idle adjustment screws? Sorry for the dumb questions...just new to Brit bikes coming from Japanese’s bikes. Thanks much.
 
Try the 'Single Carb' help and information' on RGM's website... Gives Mk2 specs and set up advice...
 
Motown1 said:
Well I did not get a chance to check timing today...other issues. I will check tomorrow. On the Boyer plate, which direction is retard/advance?

I understand the 30*@ 5000 grand...what about idle? And this Amal 34mkii....where is the bloody idle screw? I’m not trying to be dumb but all my Mikunis had separate engine idle adjustment screws? Sorry for the dumb questions...just new to Brit bikes coming from Japanese’s bikes. Thanks much.
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What do you mean by “idle screw”... pilot air screw or throttle stop screw...?

New Norton knocking help please
 
I wonder if the rockerarms have either locating springs or shims ? If not they will slide about and 'tap' when the engine is cold and pulling hard in top gear at low revs . whip off the rocker covers and have a look .. To retard ignition you move the boyer stator plate away from the direction of camshaft rotation. But do mark up before making adjustments..
 
oldmikew said:
I wonder if the rockerarms have either locating springs or shims ? If not they will slide about and 'tap' when the engine is cold and pulling hard in top gear at low revs . whip off the rocker covers and have a look .. To retard ignition you move the boyer stator plate away from the direction of camshaft rotation. But do mark up before making adjustments..
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When you say away from direction of rotation..
To Retard the ignition you turn the points/EI pick up mounting plate with Camshaft rotation
To Advance you go against camshaft rotation
In the case of the Norton to retard the timing you turn the plate anti clockwise
 
olympus said:
When you say away from direction of rotation..
To Retard the ignition you turn the points/EI pick up mounting plate with Camshaft rotation
To Advance you go against camshaft rotation
In the case of the Norton to retard the timing you turn the plate anti clockwise
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Away from does not surely mean against? No matter , you are quite correct , the ignition is retarded by turning the plate anti-clockwise..
 
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