Which Exhaust Rose Nut Setup?

Gents,

Replacing a cracked RH4 head on my Mk3 with a new Full Auto from CNW. When I purchased the bike the exhaust system had been changed to the non-balanced header pipe going into a pair of peashooter mufflers. The header pipes are the constant diameter type ending with a small flare at the end, no bulge. The rose nuts are the short ones with a split collet and washer. My question is should I replace this set up with a long rose nut and just a washer, stay with the current short thread rose nut, split collet and washer, or does it not matter either way?

Since the new head was quite the investment I am planning to replace the old rose nuts no matter which way I go.

Thanks for any help or advise!

Paul

Paul Giusti said:

My question is should I replace this set up with a long rose nut and just a washer,

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Only if you intend to fit a set of 750 pipes which may not fit as the LH Mk3 pipe is longer to fit around the Mk3 primary chain case.

Paul Giusti said:

The header pipes are the constant diameter type ending with a small flare at the end, no bulge. The rose nuts are the short ones with a split collet and washer.

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By "washer" do you mean the Mk3 spherical seating.

The information on the Andover Norton website about the short lockrings, collets and spherical seatings being for "balanced pipes only" is incorrect as non balanced flared pipes for the Mk3 are available and they use the original Mk3 fittings.


750 pipe end.


850 pre-Mk3 pipe end (requires collets still uses short lockrings).

L.A.B. said:

The information on the Andover Norton website about the short lockrings, collets and spherical seatings being for "balanced pipes only" is incorrect as non balanced flared pipes for the Mk3 are available and they use the original Mk3 fittings.

Exhausts :: Norton :: Exhaust Pipes :: 850cc :: Norton Commando 850cc MK3 Exhaust Pipes Set - WITHOUT Balance

Norton Commando 850cc MK3 Exhaust Pipes Set - WITHOUT Balance. Complete set of pipes to fit a MKIII Norton Commando. 2 pipes without balance. Outlet Size: 1+3/8 inch (35mm). OEM: 06-5256, 06-5257. Chrome plated - made in England

www.feked.com

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Perfect! That is exactly what I needed to know. Thanks.

What would be the reason to have non-balanced vs. balanced, on a mk3?

Mart UK said:

What would be the reason to have non-balanced vs. balanced, on a mk3?

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I believe the original black cap silencers should use the balanced pipe system.

With my older Fullauto head I have used these nuts since 2014. They are the best out there. I bought a second pair recently, just in case I need to have another exhaust made!

SteveA said:

With my older Fullauto head I have used these nuts since 2014. They are the best out there. I bought a second pair recently, just in case I need to have another exhaust made!

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What brand are those nuts?

jimbo said:

What brand are those nuts?

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Jimbo, as pronounced in the USA. "Cigar" Engineering. Over the pond Seager Engineeringhttps://www.accessnorton.com/NortonCommando/exhaust-threads-repair-from-seager-eng.33741/

NORTSTER1974 said:

Jimbo, as pronounced in the USA. "Cigar" Engineering. Over the pond Seager Engineeringhttps://www.accessnorton.com/NortonCommando/exhaust-threads-repair-from-seager-eng.33741/

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Yep, they are the ones....Pat Seager in Suffolk UK.....sorry for the non-functional FB link!