New Norton Owner; tuning questions

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Whether those other exhaust washers work or not, it should be mentioned that the technique for tightening them is to tighten them, then go for a ride to heat up the engine, then tighten them immediately when you drive back into your driveway. After a few heat cycles and tightening immediately after, they are usually good and sealed for a long time.

Andrew, if you haven't been retightening them, then they could be the source of your popping on the over run....
 
o0norton0o said:
Pop, pop, pop on the deceleration can be an exhaust leak. Hearing that you have some Suzuki exhaust crush washers is certainly a possible cause of the popping on the over run... Exhaust gas can generally still have some residual fuel that can burn in it. An exhaust leak sucks air in and reignites the exhaust gas. This cause particularly makes that popping sound on deceleration. Put the correct crush washers in the bike...

Other than the popping, How is the bike running? If you followed the previous instructions to return the carb settings to the recommended positions, and tuned the air idle screw as instructed, then the bike should be running well... (except for the popping)

Did you use a strobe light on the ignition timing?

*Spray carb cleaner on the outside of the intake joints as the bike is running on the center stand. Lift the throttle and spray it at the joints. If the bike stumbles, you may have found an intake leak... which would make your bike's A/F Lean...

Keep going, you'll get there...
Click to expand...

The bike is actually running very well, except for the exhaust popping. It always starts first or second kick (warm or cold), idles well and runs well with plenty of power. If I could sort the exhaust popping and general feeling that the bike is lean, I would be extremely happy.

Yes, used a strobe on the timing to check the advance settings, which were good. I had been spraying WITHOUT opening the throttle, so I'll give that a shot tonight.
 
Forget the assumption that the bike is lean... Modern fuel doesn't always show a nice tan plug like old school leaded fuel.

Run the bike, retighten the shit out of the exhaust nuts again and see if the popping stops...
 
....Also check the other exhaust joints.
And the balance pipe welds for cracks.
 
o0norton0o said:
Forget the assumption that the bike is lean... Modern fuel doesn't always show a nice tan plug like old school leaded fuel.

Run the bike, retighten the shit out of the exhaust nuts again and see if the popping stops...
Click to expand...

How tight are we talking here? They're easily snug now... to the point where I have to put a significant effort to make them turn even a little.
 
If you get any movement when wiggling the silencers, either the headpipe or the pipe / silencer joint is not tight enough.
It seems like my bike will tip over when I tighten mine.
 
they are called, "crush washers" right... Like I said, the custom is to tighten them reasonably... then go for a ride to heat them up good and you'll see they will tighten up again with little effort because they are crushing the washers as designed. I put a little anti-sieze on the threads as a lubricant to prevent gauling...

Run the bike til it's hot then tighten it good... Then go ride again and see if your popping has disappeared... and you're welcome... (if it does)
 
Thanks for the replies, everyone. Sorry for the delay in responding; life has been extra crazy the last week or so.

I installed the 21 pilot jets last night. The idle stayed pretty much the same, with the plugs coming out a nicer tan color (after testing at idle only) than previously and the amount of exhaust popping on deceleration was dramatically reduced. There are still a few small pops on decoration, but I'm fairly happy with it now and the plug looks closer to "normal" to me. I'll do some plug chops at 1/4, 1/2, 3/4, and WOT and see how it goes. I'm just happy SOMETHING changed noticeably.

Thanks for all the help!
 
maylar said:
The Suzuki crush washers are FAR superior to the Norton washers.
Click to expand...
What is better about them? Softer, compress better? Do they crush down to similar dimensions as the Norton washers? They look a bit thick in the photos which I think would take away thread engagement in the head.
 
Congrats on your progress.
Just for reference, what are the air screws set at?
 
Popping on decel: This can occur when the idle mixture is a little lean. Try turning the idle mixture screws in about an 1/8th turn and try it.

The guitar string does not work nearly as well as the #78 drill bit on the idle passageways. The stuff that clogs it is like a hard crystalline substance. I was taught never to use a drill bit in carb jets but this is an exception.
 
elefantrider said:
What is better about them? Softer, compress better? Do they crush down to similar dimensions as the Norton washers? They look a bit thick in the photos which I think would take away thread engagement in the head.
Click to expand...

They're actually steel, not copper like the Norton washers, and they have some kind of coating on them that seals better. There have been a couple different designs of the Norton washers and the early ones were really thin and squished flat when tightened. The later design is OK but I still prefer the steel ones. Yes the Suzuki washers are a bit thicker, and that's actually an advantage if you have 850 short exhaust collars (used with the crossover pipes) which can bottom out with the thinner washers.
 
maylar said:
Today, I guess. I'm certain I have some copper ones from years past.
Click to expand...


I thought the Commando ones were always steel? I've got some spares I bought by mistake several years ago (as the 850 Mk3 pipes don't use them).
 
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L.A.B. said:
I thought the Commando ones were always steel? I've got some spares I bought by misatke several years ago (as the 850 Mk3 pipes don't use them).
Click to expand...

I'll have to dig through my bone pile and see if I have any old ones to fondle and photograph.
 
maylar said:
How about ethanol free with a lead substitute added? Close enough?
Click to expand...

You tell me.
I just know unleaded pump gas cannot be used to tune, except “you are so gaddamned far rich off the map you need a compass to get back home”.
And at fractional throttle settings, it’s just silly.
If it sounds/feels/drives lean, richen it up & test.
 
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