Tight primary chain/ second gearbox adjuster

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o0norton0o said:
With Matt from CNW saying he doesn't fit one, that kind of splits the idea that the second adjuster is a necessity ... When I'm ready to do the belt drive conversion, I'll just ask him. Thank you all for your opinions.
Click to expand...
Yep - the cNw electric boot precludes any access to a second adjuster, even if you had one fitted.

Sorry - should have read #11 & #12! - but I agree
 
It is only for mechanic ease of access that the adjuster is on the right. A bike with one on the left is superior by far.
I have one on the left on my combat and the one on the right is not used except as a spacer.
The top thru bolt to case slop is excessive and I further made a custom bolt that helps prevent shifting and twisting which affects the chain or belt setting.

There is a second style of LH adjustment that is incredibly effective and much easier to use.
Concept originated by my friend with 200205* combat tune interstate (that does not exist!!).:confused:

*Edited by the moderator as dynodave later discovered the number was 202005.
 
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In retrospect, I might have done a better job at installing the dual adjuster. It came with no instructions, so I did my best to mimic the angle and spacing of the right side setup. I can get a socket on the front facing nut using an extension and swivel, but it's very difficult. Maybe if I had angled it up a bit higher it'd be easier to get a socket on it. But the rear nut is right behind the starter mount and there's no way in hell to get a wrench on it. I ended up using blue loctite and hitting the flats with a punch.

Tight primary chain/ second gearbox adjuster
 
Picture this concept . digital strap adjuster instead of analog screw adjuster like what is being sold for $ and very difficult to use..
2 flat piece of strap metal (1/8 x1" x 5")
1/2 hole in center,
Measure 5/16 hole to 1/2 hole, C-C with precision. (mine is 1.3" approx)
Then a 5/16 hole where the adjuster is currently mounted .
Make 2 straps but repeat with c-c +.040" then -.040"for each 5/16 hole.
This will give you 4 "digital" adjustment increment. each equivalent to 1 turn of 24tpi is ,041" or if desired one mm .03937".
Just by spinning the strap 180 degrees and reinstalling the 5/16 retaining bolt.nut. (of course tight it all back up)
The strap is mounted to the INSIDE of the cradle and the normal spacer washer replaced with a thinner version so the top GB shim spacing is still there.
Cheap, easy to use, repeatable and on the LH side where it matters because that is where the stress of banging gears is causing the GB to move.
You can easily make more straps if you want different "digital" increment of adjustment .
Keep track of your numbers.
Not really rocket science.
 
maylar said:
In retrospect, I might have done a better job at installing the dual adjuster. It came with no instructions, so I did my best to mimic the angle and spacing of the right side setup. I can get a socket on the front facing nut using an extension and swivel, but it's very difficult. Maybe if I had angled it up a bit higher it'd be easier to get a socket on it. But the rear nut is right behind the starter mount and there's no way in hell to get a wrench on it. I ended up using blue loctite and hitting the flats with a punch.

Tight primary chain/ second gearbox adjuster
Click to expand...

How did you locate the openings on the cradle? Interestingly, i can't find any write ups on how to do this. I'm thinking of taking a piece of paper on the outside of timing side and tracing the holes and then transferring to the drive side. Next would be cutting. A round hole easy enough, but the elongated opening? Probably a couple of holes then cut in between. I assume it fits behind the primary case.

And would you go with a threaded donut (for lack of the proper term), or non-threaded (which would need a bolt and nut)
 
TomU said:
How did you locate the openings on the cradle? Interestingly, i can't find any write ups on how to do this. I'm thinking of taking a piece of paper on the outside of timing side and tracing the holes and then transferring to the drive side. Next would be cutting. A round hole easy enough, but the elongated opening? Probably a couple of holes then cut in between. I assume it fits behind the primary case.

And would you go with a threaded donut (for lack of the proper term), or non-threaded (which would need a bolt and nut)
Click to expand...

The slot is already there. You only need a hole for the pivoting block. The adjuster I used was from Clubman Racing (Frank Cornwall) and it came with all the hardware including the banjos, one is straight through the other (left side) is threaded. I used a piece of masking tape and marked the spot for the hole using the right side as a guide.

Frank is retiring soon, and I dunno if he has any more of these left.
 
maylar said:
The slot is already there. You only need a hole for the pivoting block. The adjuster I used was from Clubman Racing (Frank Cornwall) and it came with all the hardware including the banjos, one is straight through the other (left side) is threaded. I used a piece of masking tape and marked the spot for the hole using the right side as a guide.

Frank is retiring soon, and I dunno if he has any more of these left.
Click to expand...

You are correct sir. Obviously my familiarity is lacking :rolleyes:

As an aside, Kingman Componants also carries them https://www.kingpincomponents.co.uk/norton/transmission as well as the uber expensive NYCN https://nycnorton.com/product/gearbox-adjustor/
 
I've seen it where the left adjuster is mounted backwards to make it easier to get to.
 
dynodave said:
Picture this concept . digital strap adjuster instead of analog screw adjuster like what is being sold for $ and very difficult to use..
2 flat piece of strap metal (1/8 x1" x 5")
1/2 hole in center,
Measure 5/16 hole to 1/2 hole, C-C with precision. (mine is 1.3" approx)
Then a 5/16 hole where the adjuster is currently mounted .
Make 2 straps but repeat with c-c +.040" then -.040"for each 5/16 hole.
This will give you 4 "digital" adjustment increment. each equivalent to 1 turn of 24tpi is ,041" or if desired one mm .03937".
Just by spinning the strap 180 degrees and reinstalling the 5/16 retaining bolt.nut. (of course tight it all back up)
The strap is mounted to the INSIDE of the cradle and the normal spacer washer replaced with a thinner version so the top GB shim spacing is still there.
Cheap, easy to use, repeatable and on the LH side where it matters because that is where the stress of banging gears is causing the GB to move.
You can easily make more straps if you want different "digital" increment of adjustment .
Keep track of your numbers.
Not really rocket science.
Click to expand...
This is basically what I did on my Dommie race bike. But didn't do on the 850

That's the problem with leaving bikes for 10 years. You end up forgetting everything.
 
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swooshdave said:
Is there any reason that you couldn't use the stock components on both sides?
Click to expand...

Available space?

swooshdave said:
I assume it might take a longer top bolt.
Click to expand...

I think you will find a longer top bolt and nut can't be fitted unless a section of the inner primary case chain guard is removed and why the second adjuster is threaded because it is also the 'nut'.

www.rgmnorton.co.uk

PRIMARY CHAIN ADJUSTER WITH INTERNAL THREAD, COMMANDO (LOLLIPOP)

062654M RGM NORTON
www.rgmnorton.co.uk
 
Fast Eddie said:
Given the chance, the rear chain will always pull the primary chain tight, never vice versa.

This is why you should pull the gearbox back in the slots as tight as you can, then use the adjusters to push the gearbox forward to slacken the primary chain. That way you will have taken up all of the slack in the gearbox through bolts in the direction of rear chain pull.

If you use the adjusters to push the gearbox back, you create slack in the through bolt to gearbox fit that can then be pulled back and taken up by the chain without you realising.

Comnoz once posted about this and explained it better than I can, this is just my interpretation.
Click to expand...
I had a new Norton owner adjust the rear chain without looking up how and he adjusted it to 1/2" of play with no one sitting on the bike and didn't check the primary chain adjustment at all. Then he and his son took off 2-up for a long ride. On returning home, he was seeing smoke from the rear chain (still had the chain oiler) and oil dripping from countershaft sprocket area. He made the mistake of grabbing the chain to check the tension - burned him good. Result, melted hub bearing seals, melted gearbox mainshaft seal, burned gearbox and primary oil, damaged rear hub bearing, needed two chains, and so on. It pulled the primary chain so tight that it could not be deflected!
 
L.A.B. said:
Available space?



I think you will find a longer top bolt and nut can't be fitted unless a section of the inner primary case chain guard is removed and is why the second adjuster is threaded because it is also the 'nut'.

www.rgmnorton.co.uk

PRIMARY CHAIN ADJUSTER WITH INTERNAL THREAD, COMMANDO (LOLLIPOP)

062654M RGM NORTON
www.rgmnorton.co.uk
Click to expand...
It looks like the NYCNorton unit uses a bolt but with a different approach for clearance.

Tight primary chain/ second gearbox adjuster


Or the one from Cafe Racer Parts. Although it looks a little crude with welding.

Tight primary chain/ second gearbox adjuster


Maybe adding a threaded insert to the stock piece would accomplish what some of the designs do?

Tight primary chain/ second gearbox adjuster
 
swooshdave said:
It looks like the NYCNorton unit uses a bolt but with a different approach for clearance.

Maybe adding a threaded insert to the stock piece would accomplish what some of the designs do?
Click to expand...

Yes.
 
swooshdave said:
Sometimes I amazing myself at my brilliance. :p
Click to expand...


Or, make an adjuster that fits over the original ('71-'74) circular nut?
andover-norton.co.uk

Motorcycle parts and spares for Norton motorbikes - Genuine Andover Norton Spare Parts - Andover Norton Motorcycles Parts - Original Andover Norton Parts

Motorcycle parts and spares for Andover Norton motorbikes: Andover Norton manufactures and supplies all Genuine Factory Spare Parts for Norton motorcycles built before 2002.
andover-norton.co.uk

Or, drill and tap (or weld?) the adjuster thread to the nut? Edit: The raised sections that locate in the slot might need to be cut off?
 
swooshdave said:
Is there any reason that you couldn't use the stock components on both sides? I know there is the CNW and RGM versions. I assume it might take a longer top bolt.
Click to expand...
I saw one done with stock components but the threaded portion was forward of the bolt so it was possible to get at the adjustment nuts. If I remember right, it was slightly angled down. I assume that the bolt and nut were non-standard but I didn't ask. The owner said he used it to adjust his belt tension and the normal side to straighten the gearbox to make the belt run true. I have no direct experience with it.
 
marshg246 said:
I saw one done with stock components but the threaded portion was forward of the bolt so it was possible to get at the adjustment nuts.
Click to expand...

Yes, the second adjuster is usually fitted forward of the bolt otherwise it is difficult to adjust.

Double-sided Gearbox adjuster (big pics!)

If you recall I got this piece for Christmas. I remember that I needed to drill a hole for the extra adjuster and figured it would be best to do that before the cradle gets powdercoated. I threw the cradle up on the drill press and luckily it was just big enough to handle the job. I just passed...
www.accessnorton.com www.accessnorton.com

:)

Double-sided Gearbox adjuster (big pics!)

If you recall I got this piece for Christmas. I remember that I needed to drill a hole for the extra adjuster and figured it would be best to do that before the cradle gets powdercoated. I threw the cradle up on the drill press and luckily it was just big enough to handle the job. I just passed...
www.accessnorton.com www.accessnorton.com
 
L.A.B. said:
Yes, the second adjuster is usually fitted forward of the bolt otherwise it is difficult to adjust.

Double-sided Gearbox adjuster (big pics!)

If you recall I got this piece for Christmas. I remember that I needed to drill a hole for the extra adjuster and figured it would be best to do that before the cradle gets powdercoated. I threw the cradle up on the drill press and luckily it was just big enough to handle the job. I just passed...
www.accessnorton.com www.accessnorton.com

:)

Double-sided Gearbox adjuster (big pics!)

If you recall I got this piece for Christmas. I remember that I needed to drill a hole for the extra adjuster and figured it would be best to do that before the cradle gets powdercoated. I threw the cradle up on the drill press and luckily it was just big enough to handle the job. I just passed...
www.accessnorton.com www.accessnorton.com
Click to expand...
The internet never forgets, does it? :cool:
 
To gain easier access on my Roadster, I installed the RHS adjuster facing forward the same as the LHS as I run a primary belt.
I made the LHS one myself by TIG welding some thread rod onto the LHS slotted round nut. Works a treat.
A mate with a Roadster took some smaller nuts and drilled and tapped them out to 5/16" , that gives more clearance for his spanner around the engine plates, 7/16" AF spanner (wrench).
Regards Mike
 
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