The Unapproachable Norton Commando

fastback · Joined: 18 Jul 2004 Posts: 245 Location: Toronto, Canada

I recently received my copy of the INOA Tech Digest and I am very impressed, kudos to those involved!

Given the recent discussion on oil pump servicing, I was surprised that no one mentioned the mod recommended on page 1-25 to avoid wet sumping: a ball bearing & spring inside the timing cover over the oil pump outlet.

Anyone done this mod, seen this mod or have an opinion? It seems like a logical and rather fool proof concept Wink

.

Phil

dynodave · Joined: 28 May 2003 Posts: 139 Location: USA

fastback · Joined: 18 Jul 2004 Posts: 245 Location: Toronto, Canada

Thanks Dave,

I am a bit fuzzy on the oil pump mod. Is it just a matter of sliding o-rings over the shafts? Are grooves needed.... Is this documented or discussed elsewhere- did I just miss the boat?! Embarassed

I need to tear my pump apart (again) to jog my memory!

Jason Curtiss · Joined: 14 Jun 2003 Posts: 667 Location: HOUSTON, TEXAS

fastback,

Notably, '75 MK III Commandos have a check valve in their timing cover. However, as Dynodave points out, there are other leak paths in the oil pump system that must be rectified before you can effectively cure wet sumping.

I tried out the gasket goop in lieu of a paper gasket on the oil pump of my spare engine this past weekend. I used a Permatex product, which was quite expensive. The tube of Permatex Gasket Maker cost only about $4.00 but the surface prep/activater, which comes in a spray can, cost a whopping $12.00!

Jason

Jason Curtiss · Joined: 14 Jun 2003 Posts: 667 Location: HOUSTON, TEXAS

fastback,

You need to have o-ring grooves machined in your oil pump shaft for an o-ring seal.

Jason

fastback · Joined: 18 Jul 2004 Posts: 245 Location: Toronto, Canada

Thanks Jason,

Any idea on groove dimensions - specifically the depth/shape of the grooves?

I had to laugh when you said the gasket prep was expensive! If only every Norton part were $12.00!! I'd have three running bikes by now! Laughing

Speaking of parts - I did find the lower fork shrouds I was looking for. NOS from Rabers - very reasonable price. Now I can put the front end together!!

Jason Curtiss · Joined: 14 Jun 2003 Posts: 667 Location: HOUSTON, TEXAS

fastback,

I crawled around in my attick looking for my Parker O-ring design manual but came up empty handed. So, I can't tell you the O-ring and groove details/dimensions. Perhaps Dynodave has this information.

I sure like your photograph of oil pump components; it looks like it came out of a magazine!

Personally, I don't find wet sumping to be a major problem; perhaps I've been lucky. As such, I would not go to the trouble of modifying my pump to accept O-ring seals. I do, however, believe in the O-ring concept.

Why don't you run the bike without the oil pump mods. Then if you find wet sumping to be a problem you can always modify it at that time.

Jason

Guest · Posted: Tue Dec 14, 2004 12:04 pm Post subject:

Thanks for taking the time to look for the o-ring info.

It seemed like a simple mod so why not try it while I've got the bike apart, but you are right - maybe I will leave the pump alone and see how things are - I am itching to have the bike running as it has been 4 years of slow rebuilding... and I have yet to ride an inch or hear it run... Sad

I keep falling prey to 'while I have it apart' syndrome.

I would still be interested in the information if not for this year but for next winters (Bottom end) tear down.

The photo was a quick shot on my desk with a webcam! . I used PhotoShop to clean it up and colour correct it (blue cast from my monitors). There are more photos of parts on my site, as I go over each part I try to document the process or at least the results.

Fstbk

fastback · Joined: 18 Jul 2004 Posts: 245 Location: Toronto, Canada

I got a kick out of this solution to wet sumping....

nice bike..http://garagecompany.com/bike_pic2004/yoshi/1957_matchless_g80_rr/1957_matchless_g80_rr_all.html

debby · Joined: 15 Apr 2004 Posts: 898 Location: Boulder, CO

You mean the shutoff valve? That would certainly stop the wetsumping! People have done that on Nortons too. But the first time you ride away and forget to turn it on... Shocked

Debby

Jason Curtiss · Joined: 14 Jun 2003 Posts: 667 Location: HOUSTON, TEXAS

... and its happened more than once, I can assure you. A ball valve is just too darn easy to forget about - until its too late!

However, this bike looks like a racer. So the owner probably has a check list to review before cranking it up. I'm sure that turning on the oil tank ball valve is step number one on that list.

Jason

norbsa48503 · Joined: 07 Apr 2004 Posts: 1034 Location: Flint, Michigan

Saw it happen this way. Man rides into a large motorcycle meet and is distracted by the tight spaces and eye candy. So when he shuts off the bike he forgets to turn it off. Now when he leaves he remembers to turn it on . But he has now tuned it off. He made it six miles. norbsa

piperboy.. · Guest

I admit my bike has this thing that the oil leaks into the cases...but is this really a problem?
Mine has done this for thirty years and being lucky and having a 72, the oil just gets pumped up into the tank when you start it, which can be stupid, I admit, if you have filled the oil tank up when the machine was cold(young and stupid), and the overload of oil overflows out of the tank and down in front of your rear wheel......but that only happens once...I know about it. Or if you have one of those older setups that had the tube running out of the side of the motor case and running back towards the rear tire......
Only time recently my wet sumping got strange was when the seal between the case and the primary case went bad a couple of years ago, and the oil that sat in the sump, drained into the primary case and the clutch had more than a good bit of lubrication. Strange to find a couple of quarts of 20-50 in the chain case...made it darn hard to kick over too.
I've always just started it up and let the motor run slow until I hear the telltale farting sound of the last of the oil coming out of the breather pipe into the oil tank...then I can put on my leathers and go for a ride. Maybe I've been lucky, everybody seems to be thinking it's a problem, but other than maybe causing some pressure in the cases from the pistons pumping out the oil...can't see what the worry is...something must be right about having all that good oil on the bearings for weeks at a shot.....with over 130,000 miles....(Knock on wood)...I've never had the cases apart since new....only did new rings and a deglaze twice I think and it still has the original pistons too. Been lucky maybe, or a good airfilter(wet foam like the motorcrossers use) and changing the oil at least once a year has done the trick...don't know. Maybe because I warm it up for the time it takes to put leathers and such on....
So.....if anyone can explain to me any other reason, besides the fact that it makes the stinker hard to start in the winter, that I should install one of these valve things....please enlighten me. Maybe I've indeed been ever so lucky........Never too old to learn...Ride safe! Piperboy

Stuart SS · Posted: Sat Feb 12, 2005 11:09 pm Post subject:

Piperboy

Hi ~ I have to say if you have put in all these miles on your machine ~ it would seem a classic case of ~ "If it works for you~ !"

I went down this road with dynodave, it seems a LONG time back.. with the wet sumping thing..

I for one, am one of those that has become "gun Shy" about the concept of a anti- leak valve.

I had one on my Commando and while I found one has to be EXTREMELY careful when first fitting it ~ that is; ensure the engine side to the oil pump is primed before starting up ~ I never had any problems with the thing.

BUT~ maybe it was the rumour or fact created by the crew at The norvil Shop or someone . ie: we should NEVER fit anti leak valves because if they fail it WILL result in total tradegy !

With this thought in mind .. I removed it.

I am a tad dubious about fitting the same concept, Ball and spring to the casing as this would seem to be the same thing..

As for the tap thing.. I agree .. to ~ potentially far too disasterous !

I recall when I was involved in the auto electrical trade, there was a vehicle .. which I cannot recall ~( maybe it was a Bulldozer (??) , aVolvo loader or a stationary engine setup.)

It had an illuminated push button switch, and when the ignition came on, the thing would 'pop' out sounding and an larm.. or buzzer.

Untill the operator executed the required routine, 'he' did not push the button in ~ which of course stopped the thing flashing and buzzing.

As it is not a high priority I have never gotten around to finding .. creating this fitting.
Idea

It would work great with the tap arrangement.. or simiarly wired in seqence with a micro switch would also work.

Of course this is all academic if one was to just pull the whole bloody thing apart and modify the pump in accordance with "Dave's" mud map!!

piperboy · Joined: 08 Feb 2005 Posts: 5 Location: Germany

Good idea about a "Failsafe" switch...but doubt many would put one in....we are in general not too pleased to be buzzed and beeped at...it would quickly get on most rider's nerves.
The only buzzer thing on mine is the one on my directional lights...I wear a fullface helmet and even with 30 years of riding this thing...I can't see the signal lamps without bending my head, and I forget to turn off the blinkers....and here in Germany....at an intersection...these bozos in the cars will see a blinker and even if you are doing 60 mph...they will assume you will be turning and wait till you are ten meters from the corner and still doing 60 and pull out in front of you. The driving teachers teach them to pull out if the oncoming vehicle has signalled it wants to turn, something my father went ballistic about, teaching me to wait until the oncoming car had really MADE THE TURN...and to ignore the blinker lights because people forget to turn them off. Back then, there were no automatic turn off things on blinker lights. But here...they are very well brain washed into thinking that all drivers know what they are doing and can't make a mistake, so they will pull out. After all...you did signal that you wanted to turn........ They could write that quote on the tombstones of a thousand bikers here and every year I see hundreds more , that are just tooling along and thier blinker is blinking along too. So...for myself, after three or four close calls...my load and nasty machine has a loader and nastyier buzzer that makes me turn my blinker off.

Getting back to my original question...what reason is there to stop this oil from flowing into the sump...is there some danger, does it do damage...or iis it just a case of making it hard to start in cold weather???? That:s what I would dearly like to know. At one point, I mentioned to Les Emery that I just started the bike up and waited for the oil to get forced back into the oil tank before giving any throttle...and I seem to remember getting a comment sort of like yours...that if it had been going good for so many years....that there must be something right about it. But I still would like to know what reasons people seem to have that would recommend more than a rebuild of the oil pump...which to my experience didn't change the amount of oil going into the sump much anyway. I did though once find that using Mobil1 made a heck of a lot MORE oil go FASTER into the sump...too thin a viscosity I think....and I stopped using it and went back to castrol 20-50W.
Thanks once again for all input!! Ride safe!

The Unapproachable Norton Commando

At the end of 1967 the Norton Commando was announced.