Gasp! Another silly newbie joins the fold...

So if I get an earlier side cover I can make that work with minimal fabrication and then not have to worry about the stock airbox?

If I go that route and want to keep the stock Amal carbs...what is the best filter choice?


I do want to run it first before tearing it down. The bike has been stored in avery dry climate and indoors since the rebuild was done, so Im betting that things internally are OK...but Ive got to hear it breathe first!

Portugese bearing? Point me to that...are they crap in general?

I know the stripes are paint...never had any other thought there, I was referring to the Norton logo...I am assuming that was originally a sticker...correct? If so...the vinyl ones out there should work right? Just a layer or two of clear to keep it from peeling...I would guess.

If you don't use the stock airbox you can use either style sidecover. I have an early style on my Mk3. However, it also uses an early battery box so I could fit a larger battery, and I didn't have to make a any mounts for the cover. The lower rear pin is welded to the early style battery tray.

So to use an early side cover your need the Dzus fastener (P/N 062489). The hole is already drilled on the frame. In addition you need to add a tab with a post, similar to the top rear mount for the sidecover. An easy fabrication.

Due to the close mounting of dual Amals, the single K&N filter is certainly the easiest to use. I don't know if there is room to fit individual filters. The early "ham can" won't fit to the Mk3 battery tray.

As to the logo, I prefer to paint that as well. Old Britts sell a stencil you can use, or you can take a stock die cut decal to a local vinyl sign maker and have them make you stencils. Clear coats can cause some of the vinyl decals to curl and pucker.

As to the layshaft bearing. Check here. http://www.accessnorton.com/layshaft-bearing-failure-frequency-t5132.html.
To add to confusion one of the highly recommended replacements is now apparently made in Portugal!

bugnbox said:

Portugese bearing? Point me to that...are they crap in general?

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I suggest you do a forum search using the term "layshaft bearing".

Here's how to fix it:
http://www.doov.com/apps/nortoncompanio ... s&Itemid=8

Wow...that's a bitch of a job eh?
Is this truly a common failure? I'd hate to go through all of that for nothing.
That might be a job I'd rather just sign the check for...speaking of which

Are there any good service shops in So Cal (hopefully San Diego , Orange or Riverside county?) ??

bugnbox said:

Wow...that's a bitch of a job eh?

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No, it's quite a straightforward job really.

bugnbox said:

Is this truly a common failure? I'd hate to go through all of that for nothing.

Click to expand...

It's not for nothing if it saves your life! If you did find the original ball bearing had already been replaced with the NJ roller bearing (or the FAG 6203TB phenolic cage ball bearing alternative), then you would at least know the bearing had been changed.

Any real mechanicing restoring is involved but a Commando can really test your manhood maturity will power and livelihood. There are way more, almost countless tales of digging into a old laid up but running Commando to discover stuff that would have taken out major components if not caught in time.
I HIghly reccomend a total tear down to cleaning the sludge trap then work back up making everything up to spec for peace of mind a long ways from home and life long sense of self worth you saw a major endeavor to completion.

I've gotten two '72 Combats, one constantly used since its birth just stored for winter and another left dead in a shop for over a decade. !st one had cracked cases and bend crank that was messing with drive train and could of split anytime, the other ran great after just a flush out and kicking over, but old obsolete piston and taboo Aluminum gasket were still inside and came apart 3 wk into easy just work commute legal sane usage.

Your call to take on a Commando all at once initially under your terms or random piecemeal > who knows when or where magnifying a minor to a major injury. I myself have lost all ego on my abilities and ask shamelessly for hand holding through even simple stuff last last pm putting two oil pump cogs in reversed for it to bind up when was turning fine, ugh. Only took 3 x's apart and back together to get it back to as it was, just because one screw was loose and I didn't remember if I'd left it that way or it came that way and needed inspection before install of unknown condition. Its was perfect but still took a couple hours away from other stuff. Now I'm full expert on oil pumps so don't need no stinking misleading manual on that no more. Expert enough now to know about what rpm over rev level the cast iron snout fractures off : (

Im all for saving my life...dont get me wrong there, and I dont have the ego issues that would not allow me to ask for help...in fact just plain paying someone to make it "right" when it comes to the mechanicals is not beyond me. I do admit to being a bit hap-hazzard with things at times and I know there is a risk to that. Im skilled at making things look nice, but never totally 100% confident of my mechanical abilities. I've never had any real issues with my mechanical work...when I have fixed things, they seem to stay fixed, but I always have that fear that I screwed something up somehow...and maybe that is good.

There are many ways to approach a project...I suspect every single person does things a little differently.

First I want to revive it and hear it run...maybe even a short ride down the street. Then the sights and sounds and feelings will be my fuel to make it through the whole tear down and rebuild.

Checking the bearing is sage advice and a safety issue...these are the pearls of wisdom that I love to hear...only someone that has really been there before knows it. Thank you for bringing it to my attention. :wink:

bugnbox said:

Im all for saving my life...dont get me wrong there, and I dont have the ego issues that would not allow me to ask for help...in fact just plain paying someone to make it "right" when it comes to the mechanicals is not beyond me. I do admit to being a bit hap-hazzard with things at times and I know there is a risk to that. Im skilled at making things look nice, but never totally 100% confident of my mechanical abilities. I've never had any real issues with my mechanical work...when I have fixed things, they seem to stay fixed, but I always have that fear that I screwed something up somehow...and maybe that is good.

There are many ways to approach a project...I suspect every single person does things a little differently.

First I want to revive it and hear it run...maybe even a short ride down the street. Then the sights and sounds and feelings will be my fuel to make it through the whole tear down and rebuild.

Checking the bearing is sage advice and a safety issue...these are the pearls of wisdom that I love to hear...only someone that has really been there before knows it. Thank you for bringing it to my attention. :wink:

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I heard mine run a bit and dad rode it a bit. I didn't feel comfortable riding it in its current state, especially with a gummed-up clutch. It's been several months now and it's killing me. LOL

+1 on checking the layshaft bearing, at the very least. 14K on my 1974 Roadster and I'm finally going to do the gearbox teardown this winter.

Hi Randy and welcome to the joy and the trials of Norton Ownership. One thing you will find is it can be a bit overwhelming here. We have hit you with several know Norton faults right off the bat, all while you are in the first glow of Norton ownership. Don't let the unknown worry you unduly. Nortons are robust machines when they are built right. They easily make a ridable classic that can hold its own in modern traffic. Parts are readily available from many sources and at better prices than most modern bikes. There are also many upgrades that improve reliability and rideability. I will add my 2 cents to the thread by saying that you made one hell of a deal on a very nice and seemingly unmolested late model Commando.

I will bring you down to earth a little to tell you that the layshaft bearing fix is a must. With your bike's history it is unlikely this modification has been done and it is really important that you know and not think it has been accomplished. If the layshaft bearing goes while you are sitting, you will notice that the kick start lever will swing down and point to the ground. If this happens you will walk. If the layshaft bearing goes while you are moving in will lock up the back wheel and pulling the clutch will not free it. You could get hurt.

In order to accomplish the removal and replacement of the layshaft bearing you will have to disassemble a goodly part of the bike including the transmission, clutch and primary drive. It is not as hard as it seems but it does make a nice tidy pile of parts on the work bench. What you learn here will be a prelude to many repairs and regular maintenance projects you will accomplish in the future. It will give to the incentive to collect the proper tools such as a set of Whitworth spanners and sockets, a shop manual and a clutch spring compression tool. (All musts for the Norton owner and rider.)

If it were me, I would want to see what the bores look like too. If the bike sat in snow and was locked up due to rust, there is a good chance one of the cylinder bores is pitted. This is not a show stopper but it is worth thinking about what prolonged exposure to water could have done to the bottom end.

My advice would be to get it running, it the short term, to satisfy your soul (and so that your wife knows you haven't bought a huge pile of dookey). Clean the carbs, change the oils, tune it up and putt down the street. Polish it to your heart's content but see to that layshaft bearing sooner rather than later.

Thanks for the kind words and gently applied pressure for checking things that should be checked.

History wise, after the iceberg incident, the bike was just stored away for about 15 years and hauled across the country.
In 1996 it was brought to a mechanic and everything was gone through, top end and bottom end, new bearings , brakes done, etc and a whole host of other things (unfortunately no mention of the layshaft bearing on the invoice...Drat!), then the bike was stored away again, but now indoors in the dry desert of California. Every couple of years it was fired up and run...last run about a year ago based on the tale told to me. There really is little in the way of rust apparent on the bike (with the exception of the crap in the tank)...it fell over in storage a couple times and had crap piled on top of it and leaned against it...(coincidentally in the hands of another brother of the owner...what is it about brothers??) The bike was ridden maybe about 100 miles since 1996.

I will probably pop it open at some point just to say I did, but I think the engine is probably pretty sound internally. The brakes will of course need to be redone again, the layshaft deal will be done, I will probably end up rewiring it (it came with a new wiring harness...a dead clue that SOMETHING is wrong there!) Its a full project by the time I am done with it...sure I tease myself with the weekend of tightening and tinkering and on the road I go, but I know it will not work out that way in the end...projects like this never do.

Im mentally preparing for it right now. I have never done a down to the frame rebuild on a motorcycle. Ive done it with a car before, but never a bike. Im thinking of converting a little outbuilding I have into the "operating room", clear it of all the crap, get a bike lift in there, some lights, my radio, a little fridge...there is already a toilet in there...maybe a hammock to sleep in...the perfect escape cave from everything else...just the bike and me and some tools. Schedule out one or two nights a week where I can just hide away and rebuild...it will be done before I know it.

I have a Haynes manual and the parts catalog and a decent set of tools from my car crafting... can you help me with a list of special bits I will need tool wise? What are the Whitworth tools all about? I have heard mention of them a few times...Im assuming they are of some difference from normal stuff?

bugnbox said:

I have a Haynes manual and the parts catalog

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I suggest you try to make use of the specific 850 Mk3 factory manual. You can download a pdf copy here: http://britmoto.com/manuals/Manuals/850_man.pdf

bugnbox said:

What are the Whitworth tools all about? I have heard mention of them a few times...Im assuming they are of some difference from normal stuff?

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post79263.html
http://www.moreg.org.au/whitworth.htm
http://www.sat.dundee.ac.uk/~psc/spanner_jaw.html
http://www.britishfasteners.com/threads/

So, I've looked at the closeups for about the 4th time. Whoever worked on this thing before should be strung up. That being said, I'd pull this thing down and start from scratch. Take a ton of pictures, especially the wiring. Or, what you can call wiring. Lord knows you've got enough stuff laying around there to keep you busy if you job some of it out. A 356 and what's that split window contraption?

I didn't look at the closeups before.... I agree with 850cmndo - This bike has been cobbled up cosmetically pretty bad - Wow. And he had a real bad electrical tape fetish too.

But it is mostly all there and there have been much worse on here. It will live.

Oh...it will all come apart...that is for sure...and it will live on.

Thanks for the links on the tools.

I have had decent experience with Haynes manuals before on cars...anything really wrong with it on the bike?


P.S. The grey split window-ish thing in the backround of the one photo is a 1950 Tatra.

Ive been scanning online a little for Whitworth tools...

Rather than buy a bunch of spanners I will never use...can someone clue me on on the list of what I will definitely need?

Any brands I should completely stay away from?

Thanks in advance...

Couldn't tell you exact sizes, but you won't be needing a drawer full. From my experience, SAE seems to do the trick in most places and I haven't had issues rounding things off. Checked out your pictures of the Tatra, by the way. Interesting piece. Interesting too, the reference to a Mr. Porche and Fritz.

bugnbox said:

I have had decent experience with Haynes manuals before on cars...anything really wrong with it on the bike?

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No, not really, it's just that the 850 Mk3 differs to the previous Commando models in many respects, some of them minor, and some major, therefore the information contained in the main part of the Haynes Commando manual may not always be entirely applicable to the Mk3, and the brief Mk3 supplement at the back of the Haynes manual does not give as much information as factory Mk3 manual.

bugnbox said:

Rather than buy a bunch of spanners I will never use...can someone clue me on on the list of what I will definitely need?

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You won't need many "Whitworth" tools. You will need a 1/4W (.525" hex.) slim socket for the cylinder head nuts and bolts, and a "special" ground-down 1/4W spanner/wrench for the rear head nut between the carbs-but a cheap metric wrench can always be ground to fit.

bugnbox said:

What are the Whitworth tools all about? I have heard mention of them a few times...Im assuming they are of some difference from normal stuff?

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Between metric and US you can do most anything. The only onebritish wrench I have found usefull is the 1/4 BSW COMBINATION SPANNER(head and cylinder bolts). RGM has them for around 6 pounds. On all others, 6 point wrenches and sockets will do well.