Posted: Fri Oct 29, 2004 12:15 pm Post subject: Still confused
Well, this is all interesting. A few days ago I retorqued my head and adjusted the valves to std spec's - .006 and .008. They were a bit loose, even AFTER retorquing. Hmmm. Then I got an e-mail from the former owner stating that it IS a combat, so I go out to the garage, pull the seat and tank, and readjust the valves for Combat spec's, .008 and .010. Then I read a few of these posts, than any 20M3S is definitely not a combat engine. WTF? Should I tighten them up again?
Fortunately, it only takes a few minutes to do the valves. I am used to the 12K services on my BMW K1200LT, with 16 valves, and if any are tight you need to pull one or both cams, do some math, go to the dealer and/or wait for Fedex, replace the buckets, reassemble, button up all the "tupperwear".
So - if my engine is a combat and its had the bottom end bearings replaced with the proper "superblends", that's fine. If it is not a combat, that's OK too.
Joined: 14 Jan 2004 Posts: 446 Location: Yorba Linda, CA
Posted: Fri Oct 29, 2004 12:54 pm Post subject:
Stuart, the engine # does not match with a Combat. That # appears to be a 71. Also, the Interstate was not made in 71. You may have a 71 motor slipped into 72 chassis. The black barrells don't mean anything because it's been rebuilt, most people paint these black.
The easiest difference is the breather. According to your #, the breather should be coming off the left side of the cam, in front of the barrells. There will be a hose running along the primary. If not, is the casting smooth or is there a bolt plugging a hole where it used to be.
The Combat has a rear breather exiting in the cradle area. This also could have been modified to come out of the right side case.
Another possibility is you have a 71 case tuned to Combat specs. The Combat head is easy to identify, it has a C stamped on the top. Also, the spacing between the head and barrells is noticeably smaller than the spacing on the head and barrell fins. Because it is milled.
Even if it doesn't have a C, it could have been ported and milled
to Combat specs.
Even if all this checks out to be non Combat, it is possible you have a Combat cam, which is what determines the valve lash. Unforunately, there is no easy way check this. It would be great if you could talk to the mechanic who built it and find out.
I would probably run the 8 / 10 settings until I knew.
A source I use is Les Emery's web site, www.norvil.co.uk/ click on Indentify your bike, this may help.
Notice there are 5 Mark versions. It is interesting your numbers appear to fall in the second part of the 71 or Mark III.
Posted: Fri Oct 29, 2004 1:28 pm Post subject: Details of my 72
The breather is clearly on the left, in front of the barrels, with the hose running rearward along the top of the primary. The points are at the front right corner. The tach drive is in along the front to the right of center. I just reintstalled it after having Phil at Fair Spares install a proper seal. And the oil doesn't spray out on my right foot any more.
I will leave the clearances at .008 and .010 until further notice - pretty quiet, ticks over smoothly.
Sounds like I have a '71 motor in a '72 Interstate frame. I realize only the seat, tank, and side panels make it an Interstate. Frankly, I don't care what the numbers all mean, assuming they assembled bikes based on what parts were handy on any particular day.
I am continuing to upgrade what I can, establish maintenance baselines. It starts pretty well and is WAY FUN to ride.
Thanks to all who have responded. WOW, 17 replies in less than 24 hrs.
Posted: Fri Oct 29, 2004 8:33 pm Post subject: frame number VS VIN
[quote="Jason Curtiss"]Debby,
The frame on my '75 Commando has a unique Vehicle Identification Number stamped on the right-hand side of the steering head stock. Texas and Oklahoma, and I'm sure many more states, use this number for the VIN on the title.
This causes confusion as owners may look at the flimisy red tag for the VIN and find it doesn't match the title. I came across one e-bay seller in Oklahoma that claimed the title did not match the bike. In reality, he was looking at the tag number instead of the frame number. Upon closer inspection, the frame number matched the title perfectly.
"A Thiefs Dream" sounds like the basis for a great essay!
Regards,
Jason[/quote]
The 850 frame# was a guvmint mandated thing, and was stamped on the neck of the frame. Yet the flimsy plate carried the VIN number that had long stood as nortons presentation of the actual VIN, and ususally has meaning to norton owners for norton discussions.
Changing to an entrely different subject....unerring government policy. In the US, different states do things differently. Some use the frame #, some use the VIN and some use the engine#.
Due to my overwhelming confidence in govmint beaurocracy, I generally ignore the title and registration (including Tx & Ok) and look at the VIN plate and a general look at the bike to tell the vintage. Though I will admit that TX and OK and sometimes CA may have been attempting to follow what the feds intended. It is obvious the states are not together on this and even within one state you will not get consistant titling/registrations.
Here in mass, my 75 E-start vin is 330046 not 850F130370.
I guess you just satisfy the "govmint" where ever you are and give them what ever # makes THEM happy (along with their money of course)
.
Just for the record, I feel pretty certain my registration plate is original to the bike. The bike is a 1970 Fastback and is clearly marked DEC 69. From the factory records that I've seen published, my serial number would place production square in this time frame. I've been thinking about replacing the plate because it has 35 years of wear and is as much silver as red with a few "character" marks on it. The rest of the bike is in nicer shape than the plate due to resto and refurb. I almost feel it's taboo to replace the plate. Rob
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At the end of 1967 the Norton Commando was announced.
The Norton Commando was greeted with a certain amount of scepticism because on first sight the commando appeared to comprise of the old Norton Dominator twin cylinder engine mounted at an inclined angle in a set of new cylinder parts.
It was not realized that the new Norton Commando Isolastic method of engine suspension damped out all engine vibration and produced a machine which had uncanny smoothness for a vertical twin. In due course the critics were silenced and the Norton Commando had the distinction of being regarded as the first of todays so called superbikes. There can be little doubt that the original design concept of the Norton Commando has proved correct, since comparatively few modifications of any real consequence have been made since production commenced during 1968.
Now nearly 40 years later Norton Commando riders like us are a breed of our own, and as far as we are concerned its still more fun to go for a blat on the old Norton Commando, and fast. As a Norton Commando owner and enthusiast, my goal here is to promote and give credit to those who keep the Norton name going.
It is more deserving to give credit to the Commando itself, for after all these years it continues to be respected. The original Commando designers like John Favill are those who deserve the credit for developing this incredible motorcycle.
The Norton Commando Roadster and Interstate of the late seventies, never died. Although the Norton Villiers factory dispersed the tradition lived on. Today Kenny Dreer in the USA is developing the new 952 CC Norton. What a great looking bike this is, and its engineering is still based on the original layout. It will be interesting to see how the new 952CC Norton does in todays tough motorcycle market. One thing is for sure, I would own one if I could afford it.
