1970 Commando

Go down to an Auto Supply store and buy a trailer hitch wrench, it's about 16" long with double box end and one end fits the sprocket nut just right.

Get an old drive chain, wrap it around the sprocket, and clamp the chain in a vice. Now loosen the nut LEFT HAND THREAD - so turn clockwise to loosen.

That's not a Norton part.
 
I bought a plumbers socket instead, didn't seem like I'd have enough room for the wrench with the box still in the bike. Should have bought both.

I've got a socket on the way for the air gun.
 
Yeah, it's hard to get in there while still on the bike.

With a socket, you can hold a piece of chain with a pair of vice grips.
 
NPeteN said:
I'd like to to do something practical with the old chain oil spout other than just plugging it, ideas?
Click to expand...

I just soldered mine shut. For the rivet counters I put a hose on it to make it look like it was hooked up.
John in Texas
 
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I may do that as well. Happened upon a stash of herringbone oil line, looking for an excuse to as much as I can.
 
Nuts off, solid deep socket and bar did the trick. Hard to lock the chain with no rear wheel and the bike on a furniture dolly.

Rebuilt the gearbox in the bike. Would have been 110% easier off the bike, had I been in a different mood at the time I probably would have pulled it, should have taken that advice.
Re-build was pretty straight forward, hot and cold and hammer, as I was told. Shifts nicely through all 4. Thank you Mr.Hemmings, I owe you a beer.

Destroyed the clutch mainshaft clip, so a delay on the primary until new one arrives. Replaced sprocket. Began re-assembly, space is getting tight, especially for an air filter. Wiring is organized in place for now, again, should have just done as I was told and made my own harness. Have bundles of excess wires strapped here and there, may cut them away once I get the bike where I'd like it.

Need to get my tires mounted so I can ditch the dolly and sort out the isolastics. Aside from a few useless purchases I am staying somewhat on track with my expected budget, that is to say I am not feeling thr bike in other areas of my life.

Nice bit of learning going on, looking forward to having everything off the shelves, getting myself off the ground and the bike on the road.

Also- any tips, tricks, quirks with these drums??

Thanks for reading

1970 Commando
 
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A few things;

What sprocket size did you install?? (I run a 21 tooth, not the original 19)

I have the stock dual amal carbs, but I don't use the stock air filter and it's metal housing. I use a K&N air filter made specifically for my dual amals. I assume there's something to fit your mikuni too made by K&N to filter your air intake. Maybe google it and see what your choices are there.

good job on the gearbox. That should be trouble free now with the improved layshaft bearing. Beyond that you'll now come to the clutch. The teflon lined venhill clutch cable is a recommended replacement for the original since it reduces the stiff lever force that nortons are known for. (that can be further reduced by custom thickness of steel clutch plates too) Also some people take the original clutch cable and wind it inside their headlight as a replacement in case you ever break the cable that's installed, you have a replacement on the bike. I actually drove mine home by powershifting it when I broke my clutch cable once, but it was hiway traffic, not stop and go urban traffic so I had plenty of space to make shifts up and down, then hit neutral and coasted into my driveway... lucky...

Looks good, you're on the home stretch..
 
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I've got a thin filter for the Mik. Will have to be fit with the oil tank tilted backward and then locked in place.
19T sprocket.
I've ordered that new clutch cable and will stuff the old one in the bucket. Thanks for the tip.
 
well, a few things:

First, you should have an air filter that can be installed and removed without having to unbolt the oil tank. When carbs have trouble, just being able to stick your finger in the mouth of them can verify if the body and needle are moving together as they should. Also, one of my best troubleshooting techniques for a hard to start bike is to take a squirt bottle of gasoline (that has a straw attachment) and give a shot into the mouth of the carb. If it tries to start where it previously wasn't then you persue fuel delivery as the cause of your trouble. If it doesn't try to start with the shot of fuel, then you persue ignition as the cause instead. It takes about 30 seconds to figure out which cause to persue, rather than hours... An air filter that pops on and off easily helps for a quick diagnosis.

IMO, a 19 tooth is a small front sprocket. I'm out west, so the 21 is good. I'm glad I didn't go smaller because I still have plenty of low end grunt with the 21. Some guys actually go to the 22 for real hiway cruising. Each tooth is roughly 5% difference. I really don't feel I'm missing out on any accelleration quality with the 21 tooth sprocket, and having the 19 made the bike feel powerful, but also kind of low geared. You can always change it after a season or two if it starts to strike you as a kind of low geared. For Brooklyn, maybe you won't notice all that much...

Although once you get it on the road, you have to cross the GW bridge and cruise up the palasades parkway to Harriman state park... Some of the best riding you'll find anywhere. Some crazy wide 180 degree sweepers, all traffic circle connections, and there's a great lookout called perkins memorial drive that spirals up a mountain and is a bike mecca on any nice summer weekend...
 
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You are correct Frank. Harriman/Bear Mt. are just about the only great rides in the area. I have cousins in Newburgh/Beacon, excellent motorcycle country.
Brooklyn on the other hand is appalling, you guys out west with lots of land don't know how good you've got it, or maybe you do.
Ive got about 2 inches of clearance from the mouth of the carb to the oil tank. Ill have to modify the filter I have now or hunt down one with a much lower profile. The 2.5'' mikuni throat also a limitation.
Will have to see about the sprocket, Im pretty easy to please when it comes to motorcycles.

And yes, Ive had my finger in enough carbs to appreciate ease of access.
In other news, finished the electrical work today. Just need a battery and I can start finding all of my mistakes!
 
Quick question about the rear wheel. I've got it reassembled correctly. Only issue is the speedo drive on the right hand side is creating resistance and causing the wheel to hang up. Should a certain bit of resistance be expected? I can spin the guide inside the speedo body easily enough off the bike. Thoughts?
 
NPeteN said:
Quick question about the rear wheel. I've got it reassembled correctly. Only issue is the speedo drive on the right hand side is creating resistance and causing the wheel to hang up. Should a certain bit of resistance be expected?
Click to expand...

No.
 
I use a dual layer oiled sponge sock style air filter on my single Mik carb , has a spring inside to help keep its shape , but allows you to bend it and shove into spot you choose .... It is a brand name filter , just not able to recall just now , will take a look later and post up brand ... take rear wheel down and start over making sure everything is located as intended , rear wheel should spin easy on center stand
 
Well look at that. Apparently my search bar skills need some work. Appears im missing the spacer inside the GB housing.
1970 Commando
upload a photo

Craig,
I found this filter. It is THIN. hopefully not TOO restrictive. May have to drill holes in the rear of the filter and line with foam...

1970 Commando
 
Yeah , got a set of them , for the twin 32 Mik setup I tried years ago , the red sock style filter flows much better and you have to look hard to see it .... will get out to bike shed this evening for a look ... in fact I got two of the socks for the twin carb setup and they worked great , why I still use one ....a little daft today , very low brain function , February function no doubt ....
 
Yep. I've replaced many paper filter elements with uni foam. I burn them out and then fit the foam, can be fun... I may line the original housing with foam then somehow fit an opening for the carb using the old filter I bought that was two big.

In other news
1970 Commando


It ain't much but its something.
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
 
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