bike pedigree

Not open for further replies.
May 2, 2005
I finally got wise and copied down my engine and frame #'s (which of course don't match). Turns out a frame #150693 puts the year at 1971 from a 750 while the engine #314151 makes the engine a 1974 850. From all outward appearances the thing LOOKS like an 850, but when I start tearing her down I have no idea if the swingarm will be different...or the triples....or a million other things. I've taken several picture of Frankenbike, but cant figure out how to post them here...

I'm sure many of you are scoffing that I didnt check the history when I bought the thing but I was sold on the one kick starting and the blast up to a ton. The puddle of black stuff was no deterrent. Clearly I'm not interested in museum pieces but rather a well sorted machine to get me far far far down the road. I'll add some pictures later.
Ah yes, the puddle. When I bought my bike they fooled me by not having any fluids in the bike. After a few short rides I figured it out, after adding fluids I need a coffin sized drip pan to keep my floor dry. Hope you have better luck.
Leaks arent too bad just sitting there--nothing a heathly dose of sawdust cant fix. Liberal throttle twisting causes all sorts of spits and splatters.
The resto nazis might poo-poo your bike because the numbers don't match but so what? They don't ride their bikes, they just haul them around to the occasional show inside an enclosed trailer. And their bikes don't leak oil - because they keep them drained! :lol:

My bike started life as a '71. At some point in the past the original motor got blowed up. Blowed up real good apparently as it now has crankcases from a '72. And I dealt with my pathetic TLS brake by removing it and installing a disk. So the entire front end is now '72 also, from a third bike. He's a mongrel and proud of it! 8)

So not a big fan of the drums eh? I was thinking of some brake upgrades to my bike but I've already got the disk! The rear drum on the Commando is pretty good IMO but a dual caliper up front would really be the business. Perhaps a shoehorn mod could be possible. Who's using what up front???
I also bought my 73 Commando 850 without thought to Matching #'s, I bought it off Ebay, it was 80 miles away so I could preview. The engine is 318101 which makes it a 74 model engine, nevertheless it is a beautiful bike and fun to ride. The new friends I have made are priceless so what if it is not perfect. It leaks oil just sitting there, not real bad, just marking its territory and being a work of art. The guy who installed my Mikuna said if his bike's did not leak he would be concerned.
Since the discussion has wandered a bit to oil leaks I don't feel too bad about throwing out a question related to same; what's the concensus on case sealers? Mick Hemmings promotes a product called "Wellseal" but a recent article in Classic Bike displayed a whole range of sealers, most of them not readily available in the US. Any thoughts, recommendations??

I was planning to use threebond (the gray stuff like Yamabond) on the center case joint. Not on the timing cover though - was way too hard to remove. I'll be using grease on that gasket next time!

The worst oil leaks on my engine before the teardown were actually from DPO refusing to replace gaskets and crush washers when they wore out. Replacing with correct new items made a huge improvement.

I've used the gray stringy Yamabond on split engine cases for years. I've used in on Norton, Triumph, Kawasaki and - heaven forbid - Harley engines with excellent results.

There are two types of Yamabond. One has the consistency of silicone sealer and the other is stringy. The stringy stuff works best for sealing the vertical joint on Norton engine cases.

Far Far Far Away !!!!!!! Believe me , you'll get to know the words to that song if you keep your Norton for any length of time. Only problem is , is that it will be into a cell phone and not a microphone

It goes something like this.

" Hi !!! You busy ? " I'm Far Far Away up this little back road in the middle of nowhere and this piece of sh*t has just quit and i cannot get it going "

" Any chance you can bring your trailer and pick me up "

" Oh !! by the way , bring a couple of beers "
Yup, pushing a dead Norton is hard work! :lol:

In my years of nortoneering I've only been stranded once, when the layshaft bearing came apart on the 850. On all the other occasions I was able to do a roadside repair and press on. Not much you can do about a locked up gearbox though.

Of course when that happened I was out in the middle of nowhere and it was before cell phones had been invented. So calling was not an option. I had to hitchhike home. Luckily, I survived and the bike was still there when we came back for it.

DEREK !!!!!!!!!!!!

When Bubba's Pizza can say " Over 100 Million Served " then i may change my diet but until then it will be " McDonalds "

Missed you at Mosport. Good time and a good crowd of Ontario Norton Owners

Although cell phones were actually up and running in 1947 as mobile radios the first portable cell phone was introduced in 1973 which i believe would have made you 16 at the time. Young girls should not have been out hitch hiking at the time. Any coincedence that the cell phone came out shortly after the Commando was introduced

Have a great day

It was more like 1977 or 78. Between high school and college. I still shouldn't have been out hitchhiking though.

In 1973 I was riding a Suzuki TS185. I upgraded from that to the 850. Quite an upgrade!

Hey Ron,

Yeah, I considered Mosport. I just got home from one of my infamous *&^$% work related road trips (83 flights so far this year and still climbing).

Got up to my ears in Gary Collins 750 motor this past weekend. What a mess! Some a$$hole had a cam follower slipper separate, and never bothered to clean the shrapnell out of the crankcase. Cam and rods are trash, cases are scarred up. Still had the original slotted self destructing pistons, too.

How's your motor coming?

Ron -- lucky for me there really is no such thing as far far far away in good 'ol Hawaii. My first proper motorcycle was a Honda CB400F with a weeping head gasket and shot electrics. I spent a couple of nights in Maryland cornfields thanks to that bike (of course, I knew nothing about motorcycle repair at the time). Some extra sparkplugs and fuses would have saved me from my time in the dirt.
hewhoistoolazytologin said:
Not being up on this subject...what about the sloted pistons? Mine are original I risking certain death...or what? Thanks.

According to tech digest, providing you don't ride your bike in a spirited manner (Yeah, Right...), the slotted pistons will survive. I have heard plenty of horror stories re: these pistons, and seen plenty that were cracked.

The engine that I have apart right now does not appear to have a lot of miles on it: standard bore, cross hatching still present, not much wear on the rod bearings. The pistons were not cracked. Had the valve train not had issues, it would have been run as is.

IMHO, I wouldn't run these pistons.

My $0.02,

As far as I know. Tech Digest says they were phased out in '72.

Hope I didn't alarm somebody unnecessarily :) ....


Not open for further replies.