A journey-1972 Commando Roadster

Getting those pistons out in that state is very difficult, i suggest you use at the top a rotary emery paper to clean the bore up first, then pour diesel fuel at the top and leave to soak.
What ever you do don't drill anything.
If you can then slighty move the piston downwards from the top, look at the bore again and clean rust from bore with emery cloth ( rotary cloth) and push pistons from the bottom, taking care not to hot the conrod with a hammer.
 
Took the wife out on the '73 BMW today. What a nice afternoon in southern Maryland, even if just a tad on the chilly side! How's riding 2-up on a Norton?

To pick up where I left off, while awaiting the arrival of the special tools. I ground off an Allen wrench to remove the carbs. Boy, what a pain! I spent additional time bead blasting and painting some parts. After a few days the pinion gear extractor, clutch spring compressor, and exhaust nut wrench finally arrived. Now I was able to make some good progress.

With everything in the timing side removed and somewhat cleaned up, I'm pleased with the results.

A journey-1972 Commando Roadster

Timing side without the pinion gear removed.

Next came the head. The left hand exhaust was easy to remove and the collar backed out without issue. The threads look good! The right hand was stuck though. I completely destroyed the collar trying to remove it. In the end I simply cut off the holey right hand exhaust pipe. After removing all the fasteners-the only one that broke was the hidden middle one on the top-and a little pounding, the head came off. Overall, I'm pretty pleased with its condition. I just need to extract the broken remnants of the exhaust collar. New valves, guides, springs, and maybe new exhaust threads and it should be good to go.

A journey-1972 Commando Roadster

Primary side exhaust port.

A journey-1972 Commando Roadster

Timing side exhaust port with the remnants of the exhaust collar and tail pipe. I'm hoping to be able to collapse it now that I can get a better angle on it.


A journey-1972 Commando Roadster

The combustion chamber doesn't look too bad. I just need to extract the broken spark plug.

The inside of the cylinder showed a lot of corrosion. I'm sure some of it came from hitting the head. Unfortunately, the cylinder wouldn't budge from the pistons, so my plan was to remove the remaining lower engine, split the cases, remove the connecting rod caps from the crankshaft so I can deal with the connecting rods, pistons, and cylinder separately.

A journey-1972 Commando Roadster

Corrosion in the cylinders.

With the clutch, rotor, and sprocket removed, the inner timing side case came off pretty easily.

A journey-1972 Commando Roadster

Engine and gearbox sans primary cover.

It's at this point that I get a clue as to why this bike was laid up. Everything on the engine moves except for the cylinder. I suspect the piston rings corroded to the cylinders after the bike sat for the past 30+ years. However, nothing on the gearbox will budge. That's where I left it for the night.
Bronze insrets. Jim Comstock.

 
The next evening I was back at it. As much as I tried to pound on the piston with my 1 1/2" socket, neither piston would budge. As I was about to give up, I remembered something a mechanic told me years ago. When I was trying to remove the rear axle from my BSA, the shaft was corroded to the collar that went in between the speedometer drive and the frame. It absolutely wouldn't budge. I took it to the Indian dealer down the street and asked the mechanic's advice. All he said was that I needed a bigger hammer.

So I took his advice to heart. Instead of my short 3 lb. sledge hammer, I pulled out the longer 4 lb. sledge hammer. After several attempts, that side finally budged! There was a short period of jubilation. After I got that piston out, I tried the other side. Same process and the piston on that side also came loose. Making progress!

A journey-1972 Commando Roadster

Just needed a bigger hammer.

Heating up the cylinder also freed up that broken head bolt. It came out with ease. I got the vice grips out expecting the worst, but didn't even need them.

Next was tackling the gearbox. I was very curious what was inside as it was the component that was completely seized.

A journey-1972 Commando Roadster

Gearbox in the frame.

It came out of the frame with relative ease. I could only get one of the 5 screws out of the cover. No amount of impact wrenching and hammering would get the other four out. In fact, I broke a flat blade impact tip and it cracked the outer cover. Fortunately, it was on the bottom and as I'm not doing a concours restoration, no one would be able to see it. As there was no way of setting the thing on fire like I did with the cylinders, and my wife gets perturbed when I use the oven in the house to heat up components, I lit the grill and kept it there while I ran some errands.

A journey-1972 Commando Roadster

Time to cook up the gearbox.

The next morning, despite soaking in 350° heat, penetrating oil, and some hearty swings of the 4 lbs sledge on the impact driver, nothing budged and all I was doing was stripping screws. I wasn't getting anywhere, so I decided to drill the heads off the screws. I could always remove the broken screws later.

A journey-1972 Commando Roadster

More success!

After all four remaining heads were drilled off, I took a rubber mallet and began beating around the cover. The thing wouldn't budge. That's when I found this.

A journey-1972 Commando Roadster

Cracks in all three cases.

There were cracks in the outer cover, inner case, and gearbox. And they were old, all full of corrosion. The bummer is that this is a matching numbers bike. If I can get the outer cover and inner case off, I can have the gearbox welded. However, there were now two broken areas in the outer cover, so screw it. Out with the sledge hammer and I'll beat this thing off. What I found inside after some bashing and cutting really surprised me.

A journey-1972 Commando Roadster

Enough to make a grown man weep.

I have no clue how all that got in between the outer cover and inner case, but there were some very large chunks of sand. The only thing I can think of is that this was intentionally done, but I'll never know why. I think this was the smoking gun that caused the original owner to put it under his house and forget it. However, I did find out that the kickstart and shift shafts were seized in the outer cover and that's what is holding things up, but as there won't be coming back from this anytime soon, I put it to the side to deal with much later.
 
Lordy :eek:

Cost wise, a new gearbox may be less than all the componants (assuming most everything is shot). You may be able to repair the main case if you want to keep the numbers
 
When I put the gearbox on pause, I started to disassemble the rest of the frame. First were the forks. Everything came off pretty smoothly. They did a good job with the 1 5/16" nuts on both the top of the forks and to hold the steering stem. One socket takes care of it all! Getting the top out of the bearings took a little effort, but in the end it all came out, including the bearings themselves.

Then it was time for the rear wheel. With all the rust on this bike, most things have come apart fairly easily.

A journey-1972 Commando Roadster

I think there were supposed to be some rubber bits here.

A journey-1972 Commando Roadster

More rust.


I got the rear engine cradle off and on the workbench. The swingarm was stuck. That's probably not a good sign.

A journey-1972 Commando Roadster

Stuck swingarm.

I managed to get the two covers on each side of the spindle off. The tiny, long bolt broke, but I suppose that was to be expected. I read the spindle was threaded for a 1/2"x20 bolt. The bolt didn't fit, so I got to use the tap.

A journey-1972 Commando Roadster

Threading the spindle.

I didn't have a fully threaded bolt, so I made my own.

A journey-1972 Commando Roadster

Threading the bolt.

Ultimately, it gave me a nice tool to use to pull the spindle. Unfortunately, when it was threaded in, the spindle wouldn't budge. A little bit of heat and some PB Blaster and I let it sit overnight.

A journey-1972 Commando Roadster

Putting the pressure on.
 
I tried pulling the swingarm spindle out and ended up pushing it out with a BFH
Yeah, that was a process started a few days ago. I finally got the thing out yesterday with exactly that method. I'll probably catch up on this report this evening to where I am on the bike currently.
 
Looking forward to hearing about the practical uses of that rat poison on the Norton.
The primary use was to try to repair the gas tank. After I figured out it was a lost cause, my intention was to kill the three mice around here. We live out in the country and I had a little bit of a mouse issue in my truck this summer. I never got a chance to use the poison as I caught them by hand (long story, but I felt like a ninja!).

Kills Triumph Rats.
I do love my '68 Bonnie! After I resoldered the trace on the EI plate, it's been dead nuts reliable.
 
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So after a couple of days of sitting, heating, cooling, more sitting, etc. I had to run some errands and stopped by an Ace Hardware to pick up some tools for this project. I looked at some photos online and figured there wasn't any reason I shouldn't be able to push the spindle out the other side. If I pulled it up, my sockets are only so deep. If I used various lengths of bolts, I can avoid bending a long bolt from the get go. So more heat, more pounding. All of a sudden the swingarm moved. Probably the first time in decades! Eventually I got a 4" long bolt-the longest they had at the store-flush with the swingarm. I had to use a punch the rest of the way, but as it went down, the pounding got easier. In the long run, I won!

A journey-1972 Commando Roadster

The first evidence the spindle moved.

A journey-1972 Commando Roadster

Almost there!

A journey-1972 Commando Roadster

I win!

Next was to remove all the isolastic rubbers. They all came out with relative ease. I did have to beat the shouldered end caps, but they weren't difficult to get off, just a little rusted.

A journey-1972 Commando Roadster

Dust cover off.

A journey-1972 Commando Roadster

All the components.

After a little bit of wire wheeling, I decided to go back to the gearbox. Out with the grinder and chisels! After a little bit of work and a lot of mess, I was finally able to leverage the outer cover off.

A journey-1972 Commando Roadster

What a mess!

A journey-1972 Commando Roadster

It makes me a little sad.

I tried to get the shift shaft off, but no luck. I also tried to rotate the clutch lever, but that's not going anywhere anytime soon. I did, however, get another pile of sand from inside the case. I took a flashlight to look inside and it's certainly not pretty. Hopefully I'll get a clear view of the gears soon. I was able to get all 7 nuts off the case and only one stud broke.

Question of the evening, can you take the inner cover off without removing either the gearchange ratchet plate assembly, kickstart shaft, or clutch lever body?
 
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I think they have to come off.

I would hit the whole thing with a pressure washer a couple of times and then drop ot in a bucket of deisel for a couple days before having a go.
 

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Detach the shift parts.
Remove the locking ring and remove the clutch pusher parts so the shaft nut underneath can be removed.

Download a manual at the least.
 
The long poles in your tent are the seven nuts that hold the inner cover and the clutch lever body. The lever body itself should't be a (relative) problem, but what it's hiding under it will be. That would be the mainshaft locknut and the mainshaft nut. You need a special tool for the locknut and a 1/2 whitworth socket for the mainshaft nut (15/16" is pretty close to 1/2" WW). The gearchange and kickstart spindles are connected to the inner cover (they are not connected to anything inside the body) so they can stay attached to the inner cover. In fact you can't get the kickstart spindle out without removing the inner cover. The gearchange spindle is pressed into a bush.

+1 on soaking for a long time. If that doesn't work, search on electrolysis for rust removal

Good luck
 
A guy on www.BritBike.com soaks his old rusty stuff in molasses. It is AMAZING what a great job that does! Set it in a 5-gallon bucket, in the sun for a few days. After you get the case open, pull it apart and dump everything BACK in the molasses for a few more days, then clean up real easily.
 
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