1970 Commando

That doesn’t sound right , if you specified type of handle bars and bike ... should be plug and play ... I thought
 
I bought cables for US bars. Which I assume is what I have. They are certainly not what I would consider "European" by any means. Should have just taken measurements.
 
I think there are diagrams and measurements for the different bars in the Norton Commando parts list manual ... if there is some doubt on which type of bar you have mounted .....
 
Can't find any measurements in the parts catalogue. Oh well. I'll make them work or find some shorter ones.

Only paint besides the recently painted blue.
Looks like this bike will be purple.

1970 Commando
 
NPeteN said:
Both the AN brake cable and the venhill clutch cable seem way too long. Also had to modify both ends of the venhill cable to fit my gearbox and lever. Hmmm
Click to expand...

I had a bitch of a time with routing my clutch cable with my flat bars. I had a Venhill, which is listed on their site as:

NORTON COMMANDO F/L CLUTCH CABLE
N01-3-101
1969-73 750 MODELS 'UK' - BARS; 1973-77 850 MODELS 'UK'- BARS (51" OUTER FOR ALLOY LEVERS) Clearance wire is 95mm (3 ¾)

So, of course I ordered that when I was thinking I would stil use UK bars. Wrong.

On AN on the '74 page I find:

7
CLUTCH CABLE 51", US, Featherlight (06.2492, 06.6477)
part-no: 06.2813

Hmm...

In the Mk2a parts book it lists 06.4963, and one can only find that via a p/n search on AN - not on the 74 page (which appears to have a mish mash of cables/years - except this one??!!)

06.4963
CLUTCH CABLE 48" (EUROPE Pre MK3) Featherlight

I cut my Venhill down about four inches and soldered on a new nipple. That broke off as I couldn't find the right nipple diameter. So, I ordered the 4693 cable, but the outer sheath could be a bit longer as there is too much extension on the adjuster at the bar end.
 
NPeteN said:
I bought cables for US bars. Which I assume is what I have.
Click to expand...

What are the cable lengths? What are the part numbers of the items you received?

From the photos on page 1 your Commando has the semi-Western bars 061046.
https://andover-norton.co.uk/en/shop-details/15508/handlebar-semi-western-

The original clutch cable for that handlebar was 06.2492 (now 06.2813).
https://andover-norton.co.uk/en/shop-details/15963

The brake cable is 06.2491.
https://andover-norton.co.uk/en/shop-details/15861

However, below is the early US handlebar 06.0729 (discontinued):

1970 Commando
 
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Ok, great info here. So, I believe you are correct, not US bars, most likely semi-western. So much for simplicity. Ill try to track down the appropriate cables, I have the original brake and clutch cables for reference. Should have done by due diligence. live and learn.
 
or you could find some USA bars ..... not for everyone , but ....
 
NOT going full USA on this bike Craig, not for me!
Seeing as I'm mostly sidelined until I get some electrical parts and the speedo spacer I took some time out to construct my breather and catch can. No idea where I'm going to mount it...
Fun little project.
1970 Commando


1970 Commando
 
nice work though .... you will find a spot to mount it eventually .....
 
So long as you route your breather pipe up high before bringing it down again, you really shouldn’t need a catch tank if you have a reed valve fitted.

You might be surprised how little air / gas comes out of the breather pipe.

Apart from the odd drop or two when parked, you shouldn't get any oil out of the breather I’d have thought.
 
I have the same breather and connected the pipe with a t-piece to the pipe coming from the original engine breather.
So it all runs back into the oil tank, no catch can.
 
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And speaking of cables: the front brake cable with the inline stop light switch caused an accident three weeks after completion of my bike. The front brake blocked when driving on a gravel road because the lower part of the cable housing was not located in the recess of the stop light switch body. So the brake was always "on pull". It is tight behind the 1970 lamp with "halo" and the mountings so the cable could not run freely.
Did not notice that on an asphalt road but soon after turning into the gravel road. Tank dented, rev counter ripped of, footrest ripped of, gear lever bent, etc. etc. And some bruised knees on the rider..
I mounted a solid brake cable and a micro switch underneath the hand brake lever to get the stop light working when braking.
 
In my experimenting to understand how much oil actually comes out of my 70's camshaft breather (prior to mounting Jim Schmidt's reed valve there) I swapped the rubber hose for a translucent hose. As you would expect oil was shot into the hose on the compression strokes. You could see a slow march of bubbles riding upward, thinning out as they went, then popping as they got too thin for the film to remain. When I turned the bike off they would all pop and run back down toward the camshaft port. If the port was closed, a surprising amount of oil would remain in the hose. (up to 3" ) One small bit of pressure on the kickstart would rotate the cam enough to open the port and the whole amount of oil would drain back into the cam.

This experiment was one of the reasons I route my breather back into the oil tank. With reed breathers, vs the timed breather port of the early model, oil doesn't so readily "drain back" into the crankcase because it can't get by the reed valve as easily as the timed port. I remember someone drilled a tiny hole below their reed valve to allow oil to drain back rather than remain in the hose.

I see lots of guys that say they have catch cans on their commando and it only ever has tiny amounts of oil in it. In my experience, I've witnessed enough oil exiting the breather that if I used a catch can, I would also pipe it's overflow back to the oil tank, just in case... Perhaps there's something different about the early model's timed port breather that makes it drink up more oil into it's port and expel it.

Pete as you already know, I've got 2 reed valves on my 70 model. The timing side blanking plate/mikes xs breather (like yours) and the Jim Schmidt timing port breather on the camshaft port. One on each side of the crankcase means that my bike isn't constantly pulling and pushing air back and forth between the timing case and the crankcase. Having run the stock camshaft rotating disc port alone, then in combination with the timing side blanking plate reed, and now a reed breather on both ports, I think the last version is the best. I think the second breather helps maximize the efficiency of both breathers by making a better seal on the camshaft port side. (Jim Schmidt actually did a video on that on youtube to compare the port output performance with, and without a reed installed. worth watching)

Sorry to be so long winded here,... the thing your reed breather will do is make it so your crankcase isn't heavily pressurized that you joints leak oil. The more efficiently you treat crankcase pressure, the less oil you'll leak. Your blanking plate breather looks just like mine, so I approve! If I was you, I would do what rivera did, put a tee in the 2 port hoses and route them back to the oil tank... Yes, that's what I did, so maybe there's some confirmation bias there... lol
 
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Drilling a drain hole beneath the valve is a good idea Frank.
Seems I won't know the oil output situation until the bike is running. I'd rather not have to mount the catch can and spoil the looks. The JS breather is on my list when I have a "spare" 200$.
Uli, I noticed that about the switch housing as well. Thank you for confirming my suspicions, and sorry you learned the hard way, I will go without it. DogT warned me about it back when I bought the bike, will go with something else.

Anyone have a set of euro bars they can part with?
 
This is the switch arrangement under the brake lever:
1970 Commando

Switch sits under the right aluminium plate , the left plate is bend 90 ° to close the switch when brake is not pulled.

Here is the pipe connection for the breathertubes.

1970 Commando
 
Just a note on your reassembly of the clutch. Just did my 70S and found that the new mainshaft circlip from AN didn’t sit within the recess of the clutch spacer. It was easy to miss. I filed out the recess a tad and got a nice flush fit.
 
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