need dimensional data - gearbox outer cover

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joe czech

joe czech

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does anyone know, or can anyone check the hole dimension on the outer gearbox case where the clutch cable enter the gearbox. I seem to have excessive clearance between the cable sleeve and the case.

I have a new Barnett clutch cable, and the end measures .0184" my case measures out at .199 - .015 difference - ??? don't have my original cable for any dimensional check.

thanks....
 
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joe czech said:
does anyone know, or can anyone check the hole dimension on the outer gearbox case where the clutch cable enter the gearbox. I seem to have excessive clearance between the cable sleeve and the case.

I have a new Barnett clutch cable, and the end measures .0184" my case measures out at .199 - .015 difference - ???

thanks....
Click to expand...

A .204" drill bit shank is a good sliding fit in the original cover from my 74 850.
~998cc
 
need dimensional data - gearbox outer cover


Venhill
 
thanks for the feedback. kind of new to this - was thinking it should be more of a snug fit - ;)
 
joe czech said:
thanks for the feedback. kind of new to this - was thinking it should be more of a snug fit - ;)
Click to expand...


Joe, it's a good time to be getting into Nortons! :)

I am getting back into Nortons after a 20+ year hiatus (Kids and college severely impact one's motorcycle fund!). The folks here are quite knowledgeable and have been very helpful over the past 9 months. The layshaft bearing problem was an issue I had not heard of prior to these forums.

Photo: This is an NOS cable (note the $3.95 price scribbled on it). The spigot measures .175"; the current cable on my 850 measures the same. I think Swooshdave has it right--the clearance was intended for breathing.

need dimensional data - gearbox outer cover

Regards,
~998cc
 
998cc said:
Joe, it's a good time to be getting into Nortons! :)

I am getting back into Nortons after a 20+ year hiatus (Kids and college severely impact one's motorcycle fund!). The folks here are quite knowledgeable and have been very helpful over the past 9 months. The layshaft bearing problem was an issue I had not heard of prior to these forums.

Photo: This is an NOS cable (note the $3.95 price scribbled on it). The spigot measures .175"; the current cable on my 850 measures the same. I think Swooshdave has it right--the clearance was intended for breathing.

View attachment 11137

Regards,
~998cc
Click to expand...
well, in general - it's been 47 years for me (last bike, (new) 1970 Triumph Daytona 500 - sold in 1972), forgot a lot, so everything's pretty much new and a learning experience. I like to think I've been "born again" - :D. i'm in the middle of a, part restoration, part reconditioning, part mod, part upgrade, and a lot of cleaning and detailing 74 Mk2 project. bottom line, i'm having fun - at least I keep telling myself that. speaking of "breathing" - one thing I have on my 74 is what appears to be a Mk3 upgrade to the inner gearbox casting. it looks to be a gearbox vent, so question - any Mk2 or 2a's have this from the factory?

need dimensional data - gearbox outer cover
 
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joe czech said:
- one thing I have on my 74 is what appears to be a Mk3 upgrade to the inner gearbox casting. it looks to be a gearbox vent, so question - any Mk2 or 2a's have this from the factory?
Click to expand...


Yes, it wasn't actually a 'Mk3' upgrade. The 065199 'Breather Tube' was introduced on the Mk2/Mk2A and is listed in the Mk2/2A supplement (Group 8, Gearbox Inner Cover).
 
L.A.B. said:
Yes, it wasn't actually a 'Mk3' upgrade. The 065199 'Breather Tube' was introduced on the Mk2/Mk2A and is listed in the Mk2/2A supplement (Group 8, Gearbox Inner Cover).
Click to expand...
thanks L.A.B. - so, is it safe to assume that mine is factory installed (# 319523, august 74 build date)? I was a bit puzzled by the vent, since all hardware associated with the engine, transmission/gearbox/frame mounting shows no signs of, wrench and socket tool marks indicating those assemblies were ever separated from the frame (16400 mileage). I was thinking if it was an upgrade, it could not have been installed with the gearbox in the frame. question - how do you tell a Mk2 from a Mk2a? was there a VIN or serial number cutoff or build date? I see where "kommando" stated he has a Mk2a with a November 73 build date - some 9 months before my bike build.
 
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joe czech said:
question - how do you tell a Mk2 from a Mk2a? was there a VIN or serial number cutoff or build date? I see where "kommando" stated he has a Mk2a with a November 73 build date - some 9 months before my bike build.
Click to expand...

MK2 and MK2a production was concurrent, which spec a bike was built to was determined by where it was to be sold, 2a was for Europe, 2 was for US. Very late 2A's ended up in the US possibly after they had run out of MK2 parts, just a guess.
 
joe czech said:
how do you tell a Mk2 from a Mk2a? was there a VIN or serial number cutoff or build date? I see where "kommando" stated he has a Mk2a with a November 73 build date - some 9 months before my bike build.
Click to expand...




The 'A' (Mk1A and Mk2A) 'low noise emission' models with black plastic airbox and annular discharge or black cap/bean can silencers were built for the European market where stricter noise regulations had been introduced.
As kommando says, both types were built concurrently with the Mk2 model going to the USA, therefore, an 850 after engine number 307311 can be either a Mk2 or Mk2A depending on the specification (Ham can airbox and peashooters for Mk2, black plastic airbox and black caps/bean cans for Mk2A).
 
joe czech said:
any Mk2 or 2a's have this from the factory?

need dimensional data - gearbox outer cover
Click to expand...

Not mine, it has a tube, that looks like a carburettor jet.
With no available dispatch records for the Mk2a according to AN most information would be a guess at best.
 
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The picture up the page does not have that tube.

My Mk2a.
need dimensional data - gearbox outer cover


Joe bike.
need dimensional data - gearbox outer cover
 
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Joe's picture and the AN picture posted by LAB are one and the same item and match the one on my gearbox, you could slide a tube over it, why bother though as the gearbox does not need an extra breather as the clutch cable is such a loose fit anyway it is not a sealed unit.
 
If those are the same I need glasses like Marty Feldman. :D
 
With a hammer given the no thread for 1/4" on the tube.
 
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