Exhaust Nuts

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I can't see how they would hurt anything.
It's all for fashion . . .
 
He's a good vendor. Good products and good customer support. Would think shipping might be expensive to New Zealand and
the exchange rate isn't exactly to your advantage. Maybe lose some head cooling without fins and SS doesn't conduct heat that
well. As said, it's for show.
 
My current 73 850 had a set of stainless exhaust nuts when I purchased it. The PO had his machinist brother in-law make them. They are a piece of art. Those are the pros.
The single negative is that when I removed them to put on a new set header pipes all of the female threads came out with them. The owner had not slathered on any type of anti-seize to stop the galvanic corrosion. Oh well, it gave me a reason to have the head gone through since I had to take it off to have the new threads inserts installed. Then as long as the head was off I might as well put in a new set of +10 pistons that I had kicking around. Hmm, I also had a NOS cam and lifter set so it only made sense to pull the lower end out and get on that project. Since I already had all of the parts the cost for a complete new engine was very minimal. A good friend of mine owned one of Seattle's best cylinder head specialty shops and did the head for free labor and his cost on parts. I think that I was out about $150 total for everything.
 
As I am still supplying 2 EX 1 systems, I use the chromed bronze retaining nuts (roses) and this seems to work best, and has a closer expansion/contraction rate to the alloy head.
One customer supplied some stainless ones as that was his choice, steel ones also tend to come loose more often than not.
My choice is the chromed brass items.
Regards Mike
 
I think the customer who specified stainless nuts was probably yours truly...

Thought I’d share the info for anyone interested:

I used RGM nuts on my 850 and bought their specific wrench for the same, so wanted to ‘standardise’ for the new pipes. The wrench and nut design allows for good, solid tightening. I’ve never had any issues yet.

Here’s the nuts I use: https://www.rgmnorton.co.uk/buy/exh...ared-fin-in-stainless-850-3-4-thread_1332.htm


And here’s the wrench: https://www.rgmnorton.co.uk/buy/spa...se-nuts-to-avoid-fin-damage-850-twin_1344.htm
 
Fast Eddie
You,re lucky they fitted, I bought a pair in May last year (06-3555S) and they didn,t fit my old RH4 or new Fullauto head, went in half a thread handtight and jammed solid.
A quick check with a vernier showed them to be 0.013" oversize compared to the old original chromed AN roses from the RH4.
These fitted the Fullauto perfectly and are a genuine fit and forget item on my bike, final tightening with the engine hot and never had any problems seizing or loosening on either head.

I certainly wouldn,t trust the RGM alternatives to give the same service over time given the cycles of cold, heat, moisture and possible corrosion between the head alloy and stainless roses, which expand much more than the steel originals and may present long term problems even with anti seize compound.

Sent them back for a full refund and got an email of the "I personally redrew and checked these from the original factory drawings and the appropriate British Standards (1945) so they must be correct" type from Roger Myers.
I replied along the lines of "you may well have done but they don,t fit so can I have a full refund please"
Eventually got a refund, minus the original postage despite this being a legal obligation in the UK, and emails were ignored, but from being a long time customer who has had good service regarding returns in the past, will no longer deal with them.

Obviously having been caught short, Roger got in a terminal sulk, but the fact is, I didn,t fancy the prospect of seized stainless steel exhaust roses in such an expensive, but beautifully engineered head when the standard AN roses are superior although admittedly, not as weather proof.
Caveat emptor!
 
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dart6 said:
Would these be ok without the fins or a waste of time

https://www.ebay.com/itm/NEW-Norton...CUSTOM-Exhaust-Nut-Set-STAINLESS/183543904067
Click to expand...

Hello,
I use aluminium nuts bought in EBAY. The key word is thermal expansion between the different materials of the cylinder head and the nuts the with rising temperatures. This allows the nuts to become loose. If you use aluminium nuts in combination with copper- grease and tighten them you may have to re- tighten them once. That's it. You also don't have to tighten them too hard. They expand with the aluminium of the cylinder head.
Best Regards
Klaus
 
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Klaus and 850commando
that may be the theory but the standard steel roses/nuts work fine in aluminium heads if tightened correctly with final tightening when the engine is hot as mentioned above and the fins provide a small but useful cooling function in this important area.
Stainless steel of certain grades would have a similar expansion rate to the aluminium used in the Norton heads if I,m not mistaken but aren,t better than the steel equivalents apart from rust protection.
Looking to fix a problem that,s not really there for well used street bikes although cosmetic or style considerations are a different matter for custom setups as per the smooth finless type in dart6 post.
 
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I don't see a problem with the OEM fasteners; they seem to work fine. Obviously some of the aftermarket versions look better but I have not had a problem with the OEMs coming loose or seizing in the threads. Admittedly, I use anti-seize and re-tighten when head is hot AND I safety wire them. Based on input from a serious Norton rider (more miles in a year than many of us do in ten), I safety wire everything I want to keep (which absolutely includes any fittings that hold the oil in or affect the brakes). ;)
 
This head has over 100,000 miles on it with the original Exhaust threads. To keep the threads from blowing out the nut is screwed in first without the pipe (with a bit of silicone on the threads). Putting in a couple washers before you screw in the nut is optional. A sleeve is added to the pipe O.D. so it fits inside the nut and a loop is added for the spring - both are brazed on with phosphorus bronze brazing rod (higher temp than regular brazing rod). A little silicone is smeared on the pipe O.D. where it fits into the nut to get an air tight seal. Then you just retighten the nuts after a couple heat cycles and leave the nuts in. The vibration no longer pounds out the Exhaust threads because the pipes are not fixed to the nuts (the flanges on the pipes are removed and the pipes are held in with the springs). This is a trouble and worry free arrangement and it beats the hell out of having your alum threads getting pounded out.

Exhaust Nuts
 
Last edited:
KiwiNeill said:
Fast Eddie
You,re lucky they fitted, I bought a pair in May last year (06-3555S) and they didn,t fit my old RH4 or new Fullauto head, went in half a thread handtight and jammed solid.
A quick check with a vernier showed them to be 0.013" oversize compared to the old original chromed AN roses from the RH4.
These fitted the Fullauto perfectly and are a genuine fit and forget item on my bike, final tightening with the engine hot and never had any problems seizing or loosening on either head.

I certainly wouldn,t trust the RGM alternatives to give the same service over time given the cycles of cold, heat, moisture and possible corrosion between the head alloy and stainless roses, which expand much more than the steel originals and may present long term problems even with anti seize compound.

Sent them back for a full refund and got an email of the "I personally redrew and checked these from the original factory drawings and the appropriate British Standards (1945) so they must be correct" type from Roger Myers.
I replied along the lines of "you may well have done but they don,t fit so can I have a full refund please"
Eventually got a refund, minus the original postage despite this being a legal obligation in the UK, and emails were ignored, but from being a long time customer who has had good service regarding returns in the past, will no longer deal with them.

Obviously having been caught short, Roger got in a terminal sulk, but the fact is, I will not face the prospect of seized stainless steel exhaust roses in such an expensive, but beautifully engineered head when the standard AN roses are superior although admittedly, not as weather proof.
Caveat emptor!
Click to expand...
Don't mention original factory drawings for god's sake. :eek::eek::eek:
 
cliffa
that,s what he actually wrote but didn,t follow them very well that,s all...
 
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