Commando beginner

Joined
Nov 27, 2007
Messages
4
Hello

In my search for a nice commando I have realised that I prefer the look of the roadsters, but to narrow down my search I would be happy if you could give me some input on the following:

- 750 or 850 (or Combat): Which and why? (Down to preferences, I know, but what are the pros and cons?)
- I understand that the (early) disc brakes are only a marginally better alternative to finding a soft-looking three by the side of the road to jump into. How do the drum brakes compare?
- I find the early roadsters good looking, and many of them seem to be upgraded with Mk3 isolastic, electronic ignition and belt drive. Do these offer similar levels practicality as the newer ones?
- Commando 750 S: I have been offered a nice example. Are these more valuable? Can they be identified by frame/engine number? Anything to be extra aware about regarding this model?
- Combat engine; are they as fragile as their reputation or is everything well after the bearings have been changed?

As for my comparison ability I mostly drive old italian bikes and have driven several british ones, but never a Commando.

Grateful for any input on the subject.

Regards
Shelby
 
Joined
Apr 7, 2004
Messages
1,691
Two different ways or three or four. Buy rare model restore to stock no better. Ride just to keep it limber this is the best if only dollars in dollars out are the goal. Bikes like Combat's, "S" model's , "R" models, JPN'S and on and on.
Second approach Buy 73- 74 most common 850 mod any way you like ride it, brake it, fix it, ride it, brake it, fix it, ride it.
Buy a 1975 old man's bike with electric leg do upgrades, ride it like old man.
Buy race bike or street bike that needs work or one with not matching #'s ride it like you stole it.
Have fun. Win Win.
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,107
Country flag
750 or 850 (or Combat
750
pro
Great seat-of-the-pants acceleration, especially Combats and MkV due to higher compression and 19 tooth countershaft sprocket.
S model especially sexy with the high pipes

con -
Early fiberglass tank prone to leak with modern gas (fix is to clean and line or replace with later steel tank)
Weak drum brakes on pre-'72
Those sexy S pipes tend to crack and break the hangers.
Weak centerstand on '71-'73 models. (replace with later 850 style)
Chrome fenders nearly impossible to find (replace with later stainless ones)
Wipac Triconsul handlebar switch found on '68-70 models unobtainable. (use Tricon with relay for kill button).
Pre-'73 main bearings do not hold up well to high revs. (Don't rev over 5K or replace with Superblend bearings)
Early model sidestand prone to breakage.

850
pro -

stronger crankcases with Superblend bearings
Steel tank
Disc brake front (and rear on '75)
stronger centerstand
5-plate clutch (750 has 4-plate)
electric start available on '75

con -
Disc brake front weak (sleeve master cylinder)
clutch tends to slip (replace bronze plates with Sureflex and use
Dynodave's clutch seal to prevent gear oil from contaminating plates)
Electric starter ineffective (convert to 4-pole and heavier cables or
Dynodave's Hitachi starter.)
Motor torquey, but somewhat sluggish compared to a good 750 (a machine work on the head to bump compression, a cam and it is as good as any 750)

The bottom line is they both have pro's and con's, but are not insurmountable and can be modified to work quite nicely.
YMMV
 
Joined
Dec 22, 2006
Messages
6,652
Country flag
The only Commando I have owned is my 75 MK 3 Interestate.
As one long time Norton member pointed out to me, the MK 3 has the factory upgrades that a lot of the owners of earlier bikes end up doing or would like to do.
With a pad change to those sold by Vintage brake, the front and rear discs are plenty powerful for my liking. They really only have about 2 good stops in them from 75 MPH down though. Coming down thru some hairpins following my high speed friend on his Vincent, I ran out of brakes on the third hairpin. With his stock Vincent brakes (twin drum) he did not.

This was a situation unlikely to be repeated though (steep downhill with 75 MPH to 15 MPH full on braking three times in about four miles) so the brakes are not a problem for normal, sane usage.
The late 850 engine is said to be the strongest engine in that the Crankcases have been significantly reinforced from earlier caes.
Torque output is about 17% higher than the 750s, and the Commando is all about torque. The Roadster tank looks nice, but the range is very short with that tank. If you do long mileages in remote areas like I do, the 5 .75 Imperial gallon tank is very nice.

One of the Vincent club members bought a new 69 750 Commando and rode it for a few years before selling it. He liked it so much that in 1975 when he travelled to England for a four month tour of England and Europe, he purchased a new 850 MK3. I asked him if the MK3 was slower than the 69 750 Commando as some reports indicate.
He said that the MK3 was smoother and more powerful and generally nicer. I hope this doesn't offend anyone, those were just the comments of one owner who had purchased both an early and late Commando when new and rode them both extensively.
I have also read of others who have owned both and prefer the 750.

As far as the Combat goes, if left original, yes they were very fragile.
My cousin bought a new Combat and made it 1100 miles down the road before destroying the engine. The problems with the Combat caused Norton to do a fairly major revamp of the engine (828 CC, lower compression) in order to come up with a reliable power plant that would still hopefully stay with the faster and faster Jap bikes that were being built back then.


I'm sure there are members on this board that know how to make a Combat engine reliable though.
 
Joined
Sep 7, 2006
Messages
36
Shelby:

I agree with all of the above, and let me add a few things. I also come from a vintage Italian background (1977 Ducati 900SS, 1980 Ducati Darmah SSD, 1982 Laverda Jota 180, 1982 Laverda Jota 120 and 1974 Laverda SF2). I find the Commandos make a great complement to vintage Italian bikes. Out of all of he British bikes I have ridden, the Commando comes the closest to the ride and feel of the vintage Italian bikes. No, it is does not go, stop and handle in the class of, say a 900SS, however the 750s are very light, they handle well, and their engines are quite torquey, making them very well suited for twisting mountain road and canyon type riding. I suspect Norway is very similar to So-Cal in having an abundance of this type of terrain. You also will find that you can pull your hair out just as readily keeping a Commando on the road as you will keeping vintage Italian on the road, so you will feel right at home.
 
Joined
Oct 7, 2005
Messages
1,170
After many miles of testing on the factory prototypes, I wouldn't touch one with the original (Campagnolo?) drum brake on the front. I understand there are stiffener kits or substitute backplates in the accessories marketplace that solve to problem of distortion of the backplate under load.

It was a serious shortcoming of the original. For some reason, Norton didn't do very good brakes. That's a surprise, because we didn't have an overall speed limit in the UK at the time they were being developed. I regularly cruised the prototypes at 90 mph or more on the motorways. After the Atlas, the Commando was a very comfortable high-speed cruiser.
 
Joined
Nov 27, 2007
Messages
4
Thank you all for the replys.

@Spub: Impressive collection you have there. I was actually close to buying a '78 900SS before remembering that I used to dream of a Commando. The bike in question was sold before I got round to take action, and some part of me was secretly grateful (my back, forearms and wallet, I guess).

My current stock includes a '76 Moto Guzzi 850 Le Mans, a '80 Moto Guzzi 850 T3 California (both 950cc and tuned), a '64 Royal Enfield Bullett (ridden from New Dehli to the north of Norway) and a Honda GB 500 Clubman for the wife.

As you have three of my dream bikes in your collection (four with the Commando) - how do you rate them?

Before laying my eyes on a Commando (for the xth time), I was looking at Laverdas (750 and 1000) and a Morini 3 1/2 Sport.

I have only ever tryed a '75 1000 3C and it was very smooth, very well built and very heavy. I guess the 750 will have a similar unburstable feel. As the Morini is one of the most beautiful bikes ever built, I am still thinking of buying one if I find a good one, but the spare situation is less than ideal.

What I like about the Commando is its looks, the sound and that it is relatively light for the engine size. Beeing a sucker for good sounding engines I have also always wanted a paralell twin, and the Commando is arguably the best classic paralell twin ever. (It would be blasphemy to include the 750 SF in the comparison on this page :oops: ).

The spares availability and their price (the spares - not the price of the bike) is also very comforting when it comes to any british vehicle.

Cheers
Frode
 
Joined
Sep 7, 2006
Messages
36
Frank: You must be British, for you are a master of understatement. When I got my 71 Fastback, I was very eager to give her a go, so I just kicked her over, hopped on, and started out the driveway. I applied the brakes at the end, went right through the street and into the neighbor's hedge, which I think applied more stopping force than the brakes....the Norton TLS front brake needs careful setting up to be effective, and even then serious stopping requires both front and rear. In this respect I feel the Triumph brakes of the same era are superior, so it is not the fact that the drums are not up to disc brake stopping, Norton did the rest of the bike much better than they did the drum brakes...

Shelby:

Thanks, but a LeMans 1 has always been on my wish list. I just got rid of my Centauro, and the Guzzi V-twin is an old design and the subject of derision from owners of modern bikes, but that engine has alway been one of my favorites. I would put the Commando on a par with a Laverda 750SF, the engines are similar and comparable, but the Commando handles better, due mainly to it considerable weight advantage (the SF weighs over 500 lbs, like all Laverdas it is an extremely over-engineered tank). The Commando's isolastics make it a more enjoyable bike to ride; the solid mounted SF will shake your fillings out.
 
Joined
Apr 7, 2004
Messages
1,691
Jason ,didn't you know we were saving all the mark three's for the old men with wobbly legs. That's why they sell for more money those old guys can afford it. Soft cams, heck those old guys never notice, hardly get above 55 MPH. Them mark three's is why they make big old package rails so them old men can go out and pick up bottles for the deposits and do the grocery getting put on the fishing poles. Haven't ya ever noticed that it's them mark three's is what's using all the Veter Wind Jammers up ?
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,107
Country flag
Yeah, here's a shot of my Mk3 slug. Big valves, flowed head, 4S cam, RITA, and working electric leg.

Soon to morph into a proddie racer replica with a working front brake and lighter rear brake and cartridge emulators in the forks.
Commando beginner
 
Joined
Apr 7, 2004
Messages
1,691
Now that is a rare Fastback MK3 does kinda shake off the old part. I like the idea of shedding weight do you know how much it tips the scales in this form? The "best of the parts" bikes is what make these bikes so much fun. Mine is just under 400 lbs in this state and has got a bit lighter since. Front disk skinnier tires ect.
Commando beginner
 
Joined
Apr 15, 2004
Messages
1,616
Country flag
Getting a little harsh with the Mk3 owners there, norbsa? :lol:

BTW, why did you convert to a disk? I thought you were one of those guys who said the drum brake worked better than the disk? :?

Debby
 
Joined
Apr 7, 2004
Messages
1,691
Just having fun with Jason and we got to see Ron's dressed up mark 3.
I am now saving that brake for use on my 63 Super Rocket. It's good for three hard stops than the heat gets to it. The disk is lighter and easier to squeeze.
 
Joined
Sep 7, 2006
Messages
36
Hey you guys, two VERY nice Fastbacks. I have always liked the look of a fairing on a Fastback, just never took the next step. This may prod me into finally doing it. The alloy tank and fenders are also stunning. In a Commando world dominated it seems by the Roadster guys, us Fastback guys have to stick together.......
 
Joined
Dec 22, 2006
Messages
6,652
Country flag
norbsa48503 said:
Just having fun with Jason and we got to see Ron's dressed up mark 3.
I am now saving that brake for use on my 63 Super Rocket. It's good for three hard stops than the heat gets to it. The disk is lighter and easier to squeeze.

The stock disc is only good for two hard stops and then it is overheated.
I'm surprised it works as well as it does when you consider the pad area is only something like 1.6 square inches per side, so a grand total front and rear of 6.4 square inches of brake pad area VS about 34 square inches for the drum.

Certainly discs cool better than drums, but with the tiny pad area the stock discbrake has, it has to overheat pretty quickly.
 
Joined
Oct 7, 2005
Messages
1,170
Spub:

The original front 2LS drum brake was a purchased part. I think it was Campagnolo - definitely Italian. The handlebar lever installation was Norton designed.

The problem was that after you reached a certain lever force, the force down at the brake distorted the backplate rather than apply more pressure to the shoes. I did some tests using a special lacquer to visualize the distortions. I left the company to emigrate to the US before it got sorted.

There were some crazy concepts for disk brakes tested, but they all relied on a disk that could slide instead of having a sliding caliper. The all suffered from jamming of the slide mechanism and seriously distorted disks. I believe they got Girling involved in the disk brake set-up that finally went into production, but I wasn't around Wolverhampton by then.

I guess it took a hefty front brake to show up the tendency of the front down-tubes of the frame to splay apart. You'd never have been able to develop enough braking force with the drum brake to notice it!
 
Joined
Apr 7, 2004
Messages
1,691
Yes a lot of work went into the drum to get it working re-enforcement kit,
modern compound shoes, All turned true and than scuffed in, broke in setting the linkage just so, lubed just right. Worked just as good as a stock disk but then if you were driving hard enough to need them more than three times it would start to fade off.
Now it's running the 13 MM master and the platinum pads and you can twist the weak fork legs with the brake. Never done always more to do ain't it fun.
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,107
Country flag
Yeah, the Dunstall setup on mine is being replaced with the Brembo 4-piston, 300 mm full floating disc and 13 mm Brembo master cylinder. The Dunstall is somewhere between a good drum brake and an average stock disc setup!

Greg, I haven't weighed mine, but I'm sure it is over 400#! It will be lighter with the new tank and seat setup and the rear wheel will lose at least 7# of unsprung weight with a Brembo two piston caliper and lighter rotor. I could shed more pounds by ditching the starter and drive gear and going to a small battery, but it's kinda fun watching people when I fire it up on the starter and she barks through those Conti replicas.
 
Joined
Oct 12, 2007
Messages
2,983
Country flag
Yeah, the Dunstall setup on mine is being replaced with the Brembo 4-piston, 300 mm full floating disc and 13 mm Brembo master cylinder.

Now, that's a brake! Let us know how it goes, er' stops.

Just out of curiosity, what is the ratio of caliper piston area to m/c piston area?
 
Top