Mk3 chain or belt primary ??

lcrken said:
Now I'm a little confused. The AN drawing shows 2X of item 28, the plunger and spring and 28 (one each for upper and lower plungers, I assume), but 0X of the 28A abutment spacers. In the photos below, the one for item 28 shows the plunger, spring, and plastic spacer, and item 28A shows just a plastic spacer. The dimensions of the two plastic spacers appear to be significantly different. Why the difference in dimensions for the two plastic spacers? Is the 28A and update design? The factory parts manual just shows item 28 as a set of plunger, spring, and spacer. From that, I'd assume that upper and lower plungers each have the same spring and spacer, but then I don't understand what the AN item 28A is for. Cam someone clarify this for me?

Ken
Click to expand...
Tensioner abutment can now be ordered in x 2 .
Does not help in the exploded parts diagram that 28 A part red label actually covers up the most important view to which way it inserts , thick end or narrow , top or bottom into the spring ( s ) .
Sigh .
 
Torontonian said:
Tensioner abutment can now be ordered in x 2 .
Does not help in the exploded parts diagram that 28 A part red label actually covers up the most important view to which way it inserts , thick end or narrow , top or bottom into the spring ( s ) .
Sigh .
Click to expand...
The photo below the diagram, for item 28, shows it oriented correctly.
 
L.A.B. said:
www.accessnorton.com

primary chain hydraulic tensioner assembly doesnt make sense

I have received AN new tensioner parts and included were drawings of the assembly. When assembled as shown the tensioner rubber feet go coil bound and do not reach full contraction. When I disassembled, the plastic pistons were reverse of this and their small end was inside the spring with the...
www.accessnorton.com www.accessnorton.com
Click to expand...
Interesting link. I used the original parts except for the 2 abutment spacers. I had to buy replacements as one of mine was missing and replaced with an Allen head bolt. Both had been used the wrong way round. This gave insufficient tension and my chain had been running too loose.

I was perfectly happy with the two spacers I received. When in place and oiled up, the tensioner operated fine and the chain doesn't contact the casing.

So, if you have the original springs, plungers and tensioner casting, the AN abutment spacers seem to fit when put in with the wide section against the spring.
 
Café au Lait said:
Hey guys, please forgive my ignorance but does any of this apply to my MK2 cNw with said starter?
Click to expand...
None at all, the CNW starter design is different from the factory MK3 and also uses a belt and not a chain.

See post 42

CNW E-Start

I have Matts E-start kits on my 71 ( Matt did the install ) and am nearing the end of restomoding my Dads 72, ( Pop passed at 89 last year )using nothing but Matts upgrades,including the E-start,doing this bike the way my Dad would've enjoyed it,though he would never get off the dough it takes...
www.accessnorton.com www.accessnorton.com

you move the gearbox to tension the belt.
 
This tensioner cap setup is detailed nicely in this full mk3 primary build video starting at 59 minute mark:
 

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