No restauration!

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The Commando 750 I recently purchased was a good looker for a never restored 37 y.o. bike. And the most important thing: I know her since 1984 when my friend bought her secondhand in the UK.
On the other hand I know my friend. The Norton was always ridden fast but very well looked after. All together she has now 75K miles on the clock – with the second engine.
Number one blew up after 65K miles: a conrod split the case in two halfes. Happened on the German motorway at highspeed.
The second engine was bought in parts from a guy who gave up his Norton career. I was told that he overhauled every part and had it stored over years, still separated in a few boxes.
My friend rebuilt the engine, which was not much used since then, because modern bikes like Triumph Thunderbird Sport or Voxan Café Racer where prefered in the last years.
When I purchased the bike a few months ago it was a non runner, as it stood in a shed for over a year due to illness of my friend. But a charged battery did the job and wow!- second kick she was alive! A short trip round the block made me smile: hadn’t ridden a Commando for years! I already forgot how torquey they are! And this sound!
Back home I decided not to do a complete restauration, as she really was in good running order. And to tear her apart just for the optical – never! A bit of faded colour everywhere – no problem at all! That’s patina!
No restauration!


Well, this big Interstate tank…. I never liked them. And this huge luggage rack. Don’t like this workhorse looks, no way! Might be practical but I have other bikes for touring.
And the wheels with rusty spokes. Oh well, that at least should be done. And I wanted to go for wider rims as well! And no, that’s not just for the optic! I always liked the Battlax BT45 on Jap Youngtimers. Why not trying them on the Norton?
So I got a spare Roadster tank in worst condition. And the wheels are going to be built from a professional who luckily runs his business a few miles away.
Meanwhile I had a look at the light oily cylinder base. I decided not just to retighten the nuts, but rather do the base gasket. What I found was sealing compound, which as a matter of fact is to be blamed as the culprit! Unfortunately I had to stop at this point, as I found in my sealing set the copper head gasket. From earlier experience I knew what to do: order the proper one!
Fortunately I found 32mm carbs and on further investigation a cylinderhead with well opened ports and a “C” stamped on! And the cylinders running on standard pistons, with very few carbone on their domes made me even feel better!
No restauration!

No restauration!


In the meantime I changed the liquids and washed out the oiltank. That was a good idea, the bottom was ful of slug!
Why not open the primary case? Time enough, wheels need a few weeks, gasket and small parts as well. And the clutch was unlikely very heavy to pull. On further examination I found a clutch center and discs which where far away from useful. So the next order was on the way. It always cost much more as you have planned. I should have known better!
No restauration!


Cutch parts have arrived and put together. I ordered the surflex ones with a thicker alloy plate. Goes dead easy now! As it should.

That are the facts so far. The wheelbuilder made a vague promise to have them ready by the weekend. I think he means next week or before Cristmas. Hopefully.

To be continued soon!

No restauration!
 
Nice Interstate!

Looks like an excellent refurbishing project. A full restoration is certainly not ALWAYS the order of business.
 
Andy:

The head with "C" is a Combat head, which you probably know . It has been shaved to raise the compression ratio to 10-1

You may want to keep an ear out for pinging if your gas isn't high enough octane.

If you want to use the head but don't want that high a compression you can use a decompression plate under the barrel.

I got one from Old Britts that I'm happy with.

Bob
 
Andy, Quite a few people use no base gasket and opt for a light smear of gasket compound, apparently the amount of flex in the crankcases over time can squeeze the base gasket out of position resulting in a major leak. I personally use a base gasket, but tend to regularly keep an eye on the mounting bolts.
 
No thanks, no cylinder plate to detune the engine. It run faultless the last ca.10K miles and I have no reason not to trust it’s reliability. As long as I can kick her over I leave it as it is. 8)

Have put back the base gasket without any gasket compound. And I think I do the same with the head gasket, which hopefully will be there until tomorrow when I’m back home to go on!

Cheers,
Andy
 
Hi folks,
This morning the postman finally came along with the head gasket!
The reassembling of the cylinderhead was a bit tricky though! I remembered when I was used to work on my Commandos, which was over 20 years ago, the trick is to stuff the pushrods into the head and then lower the head down to the cylinder.
Well, remembering and doing are two absolutely different things…. I needed three attempts and managed it in the end.
The head bolts where tightened as I did it in former times: without a torque wrench, because I couldn’t get access to 6 of the 10 bolts and nuts with normal sockets.
But the torque in my right arm hopefully is safe enough. I just tightened them with a spanner and a ¼” bone with extension as much as I could without killing the threads. Was always safe enough on British iron. Perhaps I should afford me a 3/8” ratchet….
But nevertheless, how do you all manage to tighten nuts no. 2, 7 and 8 (the one under the carbs and the two under the exhaust)?

No restauration!


I was glad to find the shortened Allen key for the carb bolts. It was 20 years somewhere in my toolbox! So carbs are back on. Bought me some braided oilfeed lines which where also fitted.

No restauration!


That was it so far. And it is still raining….

Cheers,
Andy
 
I find a 3/8 drive 1/4 whitworth socket and extension gets to the 7 bolts and nuts accessible from above, ring spanners get to the other 3 OK.
Mines an 850, not sure if there's any difference in the head bolting.

I gave up on the torque wrench a long time ago, had no issues.
 
Sorted!
The bike is ready for the road at the end. I'm just waiting for a good shower to wash all the f....g salt off the road.
If that will not happen in the next days, I will at least have time to install the lansdowne fork damper kit which I ordered today.
Some before and after pics:

No restauration!


No restauration!


All the best,
Andy
 
Looks great!
Is that a RGM kicker?
How do you like it?
 
Thanks guys,

that kicker is indeed a RGM item. I like to have a good lever on a Combat engine. It's well engineered and very good quality.
And you never again will see your kicker scratching your downpipe. It really turns out wide enough.
 
Andy,
Very nice. So this is a '73?? Just before the 850's? What sprocket is on it, 19 or 20 tooth? Very nice find.

Dave
69S
 
Dave,

She is from Feb.72 (2039xx), the engine dates a bit later, maybe summer 72 (2067xx).
I've got a 21 tooth sprocket on it. Good for motorway cruising, but on our small backroads 4th gear is a bit like an overdrive (~3000RPM @ 55mph).
Nevertheless the acceleration is good enough and I'm really surprised how strong she pulles from low revs, in spite of the fact that it is a Combat engine.

Cheers,
Andy
 
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