Contact-breaker chain 067705 & Cam chain

How much slack is permitted with the contact breaker chain and or the cam chain?

"Turn the distributor body, leaving 3/16" up and down movement (slack) in the top run of the chain." according to the '68 version Commando factory manual.

edited to omit incorrect info...

Thanks LAB, The link you posted to dave's site with all the different changes in castings was informative.... Failed electric start you say?? Wow!

section k here http://britmoto.com/manuals/Manuals/750_man.pdf


1/8 to 3/16 inch slack. But best to rotate several times to find the tightest point and adjust to 1/8 inch at that point.

Dereck

o0norton0o said:

It looks like your crankcase doesn't have the perch cast into the timing side to support a tensioner like my '70 commando does.

Now, seeing LAB's post, I have the feeling that I'm mistaken... lol

Click to expand...

The boss was for the original electric starter drive. :wink:

http://atlanticgreen.com/engcases.htm

20M3S late...06-1537......

...tensioner boss????? at 4-5 oclock with 2 tapped holes is for starter not magneto

Click to expand...

L.A.B. said:

"Turn the distributor body, leaving 3/16" up and down movement (slack) in the top run of the chain." according to the '68 version Commando factory manual.

Click to expand...

thank you , yes I see it now, I guess I need to print a copy of manual and read.

Not sure I have a lot "turn" available.

ordered new chains thru Andover Norton UK
had to phone in payment details at appropriate hour USA/UK -
Part No | Model | Item |Qty| Total

030080 Generic Part CONTACT BREAKER GEAR DRIVE PIN 2 GBP 3.90
067705 Generic Part MAGNETO DRIVE CHAIN NM18257 1 GBP 17.32
067546 750 - 1971 VALVE ADJUSTER SCREW NMT2074, D12/803 4 GBP 25.40
067689 750 - 1971 CAMSHAFT CHAIN NM17806 1 GBP 7.32
NM24252 750 - 1971 PLAIN WASHER, CYLINDER BASE NUT 067872 6 GBP 4.02

Net Total GBP 57.96

Andy Chain probably has the best chains.

Ta Keri get a lot of positive comments privately but few publicly.

The mag chain is real expensive.

Andy

Bought new chains for timing side from Andy and they work great like all his other chains...Have not noticed enough stretch to readjust in several thousand miles on my Atlas....