1970 Commando

My bike is a bear to kick over too. I've had the head shaved down to true it's surface, and I don't use a cylinder base gasket, so my compression is relatively high and you feel that on the kick lever, which is the sign of a fresh engine. Low compression is noticably easier to kick over, so a stiff kickstart is a good sign.

Making sure you are getting good head oiling after a rebuild is important, so good intuition to check that. Loosening a banjo bolt for a second when it's running usually makes a mess and proves you are oiling the top...

I don't have a mikuni, so I can't help you with that tuning info. If you need to turn the idle screw up to keep it running while you mess with that air screw, I think that's standard proceedure for any carb adjusting. Then once your engine feels strongest, back down the idle speed screw.

Sounds like you are close to going for a ride... cool!

Yes Frank, I am very excited. Will spend tomorrow getting an idle, maybe take her for a spin then look into a proper paint job. Looking forward to taking some nice outdoor photos as well. Clutch pull is strong even with venhill cable and proper adjustment... Good forearm workout. Feeling good.

the clutch pull tension can be adjusted by changing the height of the stack of plates in your clutch basket. It's been so long since I did mine I forget the entire process. As I recall, you add a metal clutch plate to make the stack taller, but a normal thickness plate makes it too tall, so you buy a custom made thinner metal clutch plate and the new stack height gives you a significantly lighter pull.

That's something you can look into later, by searching the forum... I look forward to the pictures of Brooklyn and the bike... Last time I was there I went to Lundi's for dinner in sheepshead bay...

There are also 2 different thicknesses of pressure plate, so you can trade and swap to come up with the ultimate lightweight pull if you work at it a bit.

I have read about that a bit. Can the thinner pressure plate be paired with the existing clutch plates or should I look into replacing all plates to a later design?
Got the bike idling for a bit earlier. Getting alot of exhaust/smoke from around the header at the exhaust collar, need to torque the collars with a bar once I can get the engine hot enough. Very nice sounding exhaust. Things keep getting better with this Norton.

I bought a pair of thinner steel plates from "oldbritts". I'm sure they are stock plates that are surfaced down to be thinner. I think I bought 2 different thicknesses so I'd have some adjustment with my stack height. As I recall, I used one of them, and it was good enough that I didn't bother to test the other...

Great, thanks for the advice. I'll look into replacing the plates if the pull proves to be too much.
Quick question- does the oil junction block take a washer at the banjo bolt? Can't seem to find a definitive answer on AN or Old Britt's. Mine is currently washerless and leaking.... Guess that answers the question?

NPeteN said:

Quick question- does the oil junction block take a washer at the banjo bolt? Can't seem to find a definitive answer on AN or Old Britt's. Mine is currently washerless and leaking.... Guess that answers the question?

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Sounds like the junction block gasket isn't fully sealing the joint.

https://andover-norton.co.uk/en/shop-details/14972/gasket-oil-junction-block

Be careful with that gaskets alignment, this is how mine came.

Ah, I will put this one the list! Just to confirm, no copper washer on the bolt then? Thanks all

Where’s the alignment bushing.

Also the junction block output tubes are sweated into the junction block. Mine eventually started leaking at the solder joint, so I fluxed it and resoldered the pipes which stopped the leak for now. I thought about buying the billet junction block which is made as a replacement which would be less prone to break, but I'm cheap, and my fix worked...

Mwood7800 said:

Where’s the alignment bushing.

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You can barely see it in the bottom hole in the case because of the angle of the photo. And you can see how there was enough play in the bolt holes of the gasket that was allowed to rotate. A little smear of gasket seal on one side when I put the new gasket on the case should keep the new one in place.

Had the bike outside today. Looking for advice with the single mikuni, a good starting point. Had her going here and there but pretty sure the excessive kicking was hampering anything constructive I was doing with the carb. That, added to an inconsistent supply of gasoline (tank is being painted) didn't help. So looking for advice on the mikuni AND also, when I had the bike going I got ALOT of smoke, nothing thick, just haze/ steamy smoke from the headers and mufflers, I figure not being helped from extensive kicking and carb fiddling.
I'll give the old girl a break until I can rustle up some sound advice, maybe post in the general forum thread as well.

Edit: the bike had wet sumped over a week or two sitting, explains the smoke, figure the smoke from the head/headers is down to the collars not being fully tightened yet.

Hey Pete, it's gotta be pretty hard to run the bike without a gas tank, which makes troubleshooting kinda' difficult too. As far as smoke goes, black smoke out the exhaust pipe is excessive fuel, and blue/white is oil. You can expect that on first start ups after a rebuild oily surfaces will burn off the oil, causing some smoke. Smoke off the outside of the pipes from oily hands touching them burns off fast too, once the bike runs for a few minutes.

I can't help much with the mikuni specifically, but I will add that you should develop a specific procedure for starting your bike and be aware of what modifications to that procedure produce an instant good result. Things like holding the throttle open/half open/closed should be part of your experimental procedure to see what works. Eventually, you'll learn what works best to save kicking the bike over excessively to get it started. Bare in mind that this procedure will be your "cold start" procedure, and when the bike is hot, that procedure may vary so you'll have to learn what to do when it's hot too.

I have 30mm dual amals. I never use the choke, where as some other people always do that to start their bike cold. Instead, I hold the slides half way up to give the bike a good gulp of fuel. It fires first or second kick. I never kick it when it's resting on either stand. I balance the bike on it's wheels to avoid premature wear on my stands. Good luck!

Good point Frank, I had not considered the myriad of substances smeared here and there over the past 6 months burning off.
I tend to err on the side of caution when white smoke starts to envelop the FRONT of the bike.

Suppose I'm better off waiting on the tank to sort things out with the carb. Will have to exercise a bit of patience!

I have starting procedures for my other bikes that are MUCH easier to kick over. I can see why you guys aim for one or two kicks. Much respect to you guys at more advanced ages.

Great information here on your thread.

Send up some pics when u can.

BusDriver330 said:

Great information here on your thread.

Send up some pics when u can.

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Not much to see right now. Waiting on paint, then some better weather for some nice photos. Then, when the engine explodes I'll be back with more pictures!

NPeteN said:

Not much to see right now. Waiting on paint, then some better weather for some nice photos. Then, when the engine explodes I'll be back with more pictures!

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Ha ha, you sound like me.... A story: My automechanic friend (in new york btw) helped me with my rebuild by sending my parts to his machinist who builds race motors for boats. The guy did my Ford Van too... Anyway, I got the bike together and rode it weekly with my mechanic friend on his ducatti, but I was always saying to him, "It should blow up any day now".

Eventually, my mechanic friend gave me shit about my poor attitude and said, "You're always putting the Norton down. Has it ever conked out and left you stranded on the side of the road?" I answered him that it hadn't actually, except for the time I ran it out of gas which is my fault not the bike's. He thought I did a pretty good job putting it together, and I wasn't abusing the engine when we rode, so he saw no reason that my bike would fail, and that I was just being superstitious because I wasn't a professional mechanic. As a pro, he thought it would hold together for a long time if I didn't abuse it or run it out of oil on a ride...

You've been diligent. You should have a good running bike for a long time. With the exception of losing a follower pad while idling in the driveway last summer, the current rebuild has been solid for over 20 years.

Frank, your story probably rings true for MANY riders who work on and ride older machines. Certainly does for me! Perhaps if we had more threads like "20 carefree years on my Norton" instead of "engine exploded. WHAT NOW?!?" Our expectations might be more optimistic!

For now only time will tell. A lot of these machines had lives long before we got to them. Change the oil, filter the gas, be nice to the gearbox. What more can we do?