MK2 Exhaust Pipes

Just wondering if exhaust pipes for the MK2A Commando will fit the MK2 model?

We discussed this only a few days ago.

You are much more likely to find MK2 pipes over MK2a, Andover Norton have been promising some MK2a pipes for years and no sign of making them available.

L.A.B. said:

We discussed this only a few days ago.

Mark II vs. Mark IIA

This may be obvious to some but I am thoroughly confused. How do you differentiate between the Mark II and the Mark IIA models. What are the distinguishing characteristics. My bike’s serial number is 310697 which I think might be a Mark II?

www.accessnorton.com

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I appreciate your patience but I’m still a little confused. (Seems to be a more or less permanent condition these days.)

Feked has balanced and unbalanced exhaust systems for the MK2A on their site. The end treatment of the Feked MK2A pipes appears from the photos and info on their site to match the end treatment of the exhaust pipes which I am replacing on my MK2. The diameters of the engine side and the silencer side of the pipes (41mm and 35mm respectively) are exactly the same as the pipes I am replacing yet Feked has advised that they can only guarantee the pipes to fit the MK2A as the part numbers for the exhausts on the MK2A and MK2 are different. My confusion relates to why parts that appear to be identical would have different part numbers?

WEM said:

I appreciate your patience but I’m still a little confused. (Seems to be a more or less permanent condition these days.)

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I agree it's rather confusing and made worse by the addition of unbalanced pipes being listed under the same part numbers as the balanced pipes.

WEM said:

Feked has balanced and unbalanced exhaust systems for the MK2A on their site. The end treatment of the Feked MK2A pipes appears from the photos and info on their site to match the end treatment of the exhaust pipes which I am replacing on my MK2.
The diameters of the engine side and the silencer side of the pipes (41mm and 35mm respectively) are exactly the same as the pipes I am replacing yet Feked has advised that they can only guarantee the pipes to fit the MK2A as the part numbers for the exhausts on the MK2A and MK2 are different. My confusion relates to why parts that appear to be identical would have different part numbers?

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The numbers (06-3397 & 8) Feked are quoting are the 850 Mk1 Roadster pipe part numbers not Mk2A (065256 & 7 same as 850 Mk3).


Looks like other suppliers also have either the wrong Mk1 part numbers for the Mk2A pipes or they are also supplying the wrong pipes.

My MK2a has had the following pipes fitted over the years, always with peashooter silencers under my ownership and other than the need to use spherical seats with the MK3 pipes no fitting difficulties.

1. Possibly the original MK1a balanced flanged pipes (carry over as mine is a very early MK2a) with peashooters and no spherical seats. (blackcaps would have been replaced at some point before I bought the bike, holes are redrilled in the mounting plates to suit the peashooters but then later on peashooter mounting plates were fitted and the proper holes used)

2. MK3 balanced flared pipes with peashooters and with spherical seats.

3. 750 unbalanced flanged pipes with peashooters no spherical seats.

4. Next step will be back to 2 using RGM's MK3 balanced flared pipes with spherical seats.

All these pipes are the same diameter 1 3/8" so the peashooters of several makers have all fitted.

Why not buy pipes in Canada so returns are easier.

kommando said:

1. Possibly the original MK1a balanced flanged pipes (carry over as mine is a very early MK2a) with peashooters and no spherical seats.

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Yes, it seems the early Mk2A probably had the Mk1A flanged pipes (064202 & 3) however, they do not appear in the Mk2/2A supplement so had been changed to the flared end (065256 & 7) pipes by publication (sometime during or later than Jan. '74?).