Progress on my 1973 Hi-Rider to Roadster changeover has stalled for a while as another project has taken precedence. Before stalling had replaced the entire exhaust system (w/peashooter mufflers) from the aftermarket system that the PO had installed. Want to ask are the offset stepped muffler (silencer in Norton speak) brackets that claim to give an additional 3/8" of clearance for the kick start lever a worthwile addition? Haven't even tried to kick it through since installing the new exhaust system. I have to wonder, since if was an issue why wouldn't Norton have made a change. I see a member here on the forum have a set for sale.
Stepped exhaust mounting brackets
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concours
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Yes.
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The NOC wrote a whole book on things that could go wrong and how to fix them and that was in the 70's and 80's. Why would the factory need to fix anything to make the book redundant.
Anyways the NOC book blames the exhaust being hit by the introduction into the spares market of pattern kickstart levers.
I fitted a genuine MK3 kickstart lever which is one inch longer and it never hit the exhaust but then I test as I fit the exhaust and use the spherical seats in the head so the pipes have some movement.
Anyways the NOC book blames the exhaust being hit by the introduction into the spares market of pattern kickstart levers.
I fitted a genuine MK3 kickstart lever which is one inch longer and it never hit the exhaust but then I test as I fit the exhaust and use the spherical seats in the head so the pipes have some movement.
marshg246
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The stepped brackets do step the mufflers in some, but they did not stop my kickstart from hitting. Supposedly. a true MK3 lever will. However, every one I've bought saying it's MK3, is not. I assume that the AN MK3 lever actually is a MK3 lever, but I've not tried one. The RGM T140-type level actually stops the problem and makes them easier to start, but they are often out of stock, and they have QC issues.
Most of the hitting can be stopped by putting it all together loosely, pushing in on the pipe while tightening the rose, then the muffler mounts and finally the clamp. This is NOT the factory recommended way!
Why would Norton have not fixed it? They took a stab at it for Interstate and Interpol, but I guess it wasn't important to them until the MK3.
Exhaust-related service releases (that I know of):
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I run either the Mk 3 or RGM kicker and adjust the pipes.
Had an issue with a 'Pattern' pre Mk 3 kicker.
The interesting thing is, don't remember it being an issue with my original Mk1 850.
Stock cross over headers, stock kicker.
If you look at original 750 pipes, they come out out of the head angling towards the front and then sweep down following the frame. Much tighter than current aftermarket pipes. Look at original 850 pipes and they sweep in tight to the frame.
Stock Mk 1 pipes will not fit on a Mk 3 as they hit the primary.
So I agree with whoever that the problem originates with the pipes.
The Mk 3 design allows movement on the spherical washer for alignment.
Had an issue with a 'Pattern' pre Mk 3 kicker.
The interesting thing is, don't remember it being an issue with my original Mk1 850.
Stock cross over headers, stock kicker.
If you look at original 750 pipes, they come out out of the head angling towards the front and then sweep down following the frame. Much tighter than current aftermarket pipes. Look at original 850 pipes and they sweep in tight to the frame.
Stock Mk 1 pipes will not fit on a Mk 3 as they hit the primary.
So I agree with whoever that the problem originates with the pipes.
The Mk 3 design allows movement on the spherical washer for alignment.
robs ss
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Where did you get the spherical seats?
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I made up my own "Stepped" mounting bracket for the r/h muffler and straightened out the kick lever to give better clearance. I must admit I do like the look of the earlier front pipes as on my 750. Can't seem to find anyone who stocks the original type.
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They were used with the MK3 balanced pipes with the flared ends but you can use them under the normal flanged ends.
Andover Norton - EX. PIPE SPHERICAL SEATING - 06.5259
EX. PIPE SPHERICAL SEATING
andover-norton.co.uk
They allow more manipulation of the pipe position but the downside is less thread engagement for the exhaust nuts. As I use bronze nuts tightened on a running engine that has never been an issue with my bikes. You can drop the sealing rings to increase the thread engagement, any gaps get filled with carbon quickly or just live with the exhaust popping on the overrun.
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Not sure if he stocks them, but he lists them.
May I ask how Norton, as you say "took a stab at fixing it for the Interstate and Interpol"? Different exhaust mounting? Different kickstart lever? And do the referrences to "pattern" kickstart levers refer to aftermarket replacements? This is the only Norton I've ever had or been around.
marshg246
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Read the first link I gave.
lazyeye6
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The original kick start lever on my '74 Roadster would nick the exhaust muffler. I bought and fitted a Mk3 lever and that fixed it, though an
expensive fix. My late '74 Interstate (low pipes) is all original and came with an offset muffler mounting bracket on the right side. Kickstart
lever clears it easily. A/N website shows a unique pair of offset mounting bracket's for the MK3 Interpol model. For the MK2 model they
show a single right hand offset bracket for the right side.
Andover Norton - BRACKET - SILENCER RH (INTERSTATE) - 06.3579
BRACKET - SILENCER RH (INTERSTATE)
andover-norton.co.uk
I read the link you sent. Thanks. I wonder if that was enough to actually cure the problem.
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Yes
After all the responses about this issue, got out to the shop yesterday and carefully kicked the bike through for the first time since installing the new exhaust system. I have a shade over 7/16" of clearance between the k-start lever and the muffler. I did not use the stepped mounting brackets, the spherical seats, or did any special assembly procedure when installing the exahyst system. In my case anyway, I don't see a need to do anything to gain any additional clearance. I do appreciate all the suggestions if I were to have needed to gain clearance. I do realize assembly tolerances were very different 50 years ago, and many exhast pipes/systems/mufflers have been changed, but seems odd that on one end of the range, the lever actually hits the muffler, but in my case there is nearly 1/2" of clearance. Thanks for all the help.
concours
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There is so much more.
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