Commando Quarter Mile Times (2014)

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What have drag strip times got to do with anything ? If you use the bike normally, you ride it around corners before you come to the straight bits. The speed down the straights is very dependent on the speed you are carrying around the corner and how soon you can safely get on the gas.
 
I will weigh my 850 mk3 when I get the rear wheel back on. Can't recall the exact number now, but I had a weigh- in day a couple of years ago and was surprised how close in weight the MK3 was to the 650SS, which is supposed to be 408lbs dry. I remember thinking, remove the starter mechanism, big battery and put the same amount of fuel in both, the weights were within about 15 pounds, the 650 being lighter. Not much considering the 650 ss is known as a light bike and the MK3 is a heavy.
Other than the starter mechanism, there just isn't much else different about the mk3 that would add 90 pounds to the earlier Commando weight.
Weight numbers get thrown around a lot and most are inaccurate.
Sport Rider publications weighs each new sport bike they review. The numbers , both dry and with fluids are always way above the manufacturer's claims. Bikes like the Honda RC51 have become know as pigs because Honda published a reasonably accuratecweight for the bike. Bikes such as the GSXR and R1 are known as featherweights due to misleading numbers that have been published. In reality most litre Sportbikes built in the last ten years all weigh about the same, about
470-485 pounds ready to roll. The pig Honda RC51 is no heavier than some model years GSXR.
I suspect it is the same with the MK3, which was a bit heavier due to the starter and became known as the "heavy'' Commando.

Glen
 
1up3down said:
One other mention 1up,
Your reports stop in June 73, then pick up in 75, leaving out all previous 850's with the black box fitted.

there were two road tests of the Mark 2a with the black box, both did not run drag strip tests

I believe they went from stop watches to calenders for black cap bikes.
 
1up3down said:
and the Mark3 at 495 ("curb" at 522)

According to the Mk3 manual the dry weights are:

Dry Weight includes battery, but not petrol, oil and tools
Roadster 465 lb. (211 kg) Interstate 475 lb. (215 kg).

The only reference to a "curb weight" (inc. half a tank of fuel) "of 522 lb." that I know of, is in the Cycle World Dec. '75 issue, (included in the 'Norton Commando Gold Portfolio' book) however that particular Mk3 was an Interstate fitted with a Vetter touring fairing, K & Q seat and crash bars.
 
1up3down said:
Phil Yates posted:
The MkIII was the heaviest Commando but not "much heavier". Still can't find my reference on this matter, but it certainly wasn't enough to effect standing quarter times to the extent you have mentioned. Different rider weights would have a similar weight variation as MkIII versus previous 850's

well actually, yes, the Mark3 is quite a bit heavier

dry weight for stock 750s for example are quoted at 400 pounds, 850s at 430, and the Mark3 at 495 ("curb" at 522)

yes Phil, different rider weights could have an impact, and as they are not quoted in the road tests we have no way to confirm that for example a much lighter rider could have been on the Mark3 quarter mile tests any more than a heavier rider on the pre 75s, think it far to assume that test riders are generally around the same weight unless you think that was a significant reason for the almost two second quarter mile time difference?

safe to say that the Mark3 is slowed down by multiple factors including its weight and induction

An earlier reference in here mentioned an addition MkIII weight of 20lbs above earlier 850's. I would have thought this closer to being correct than 65lbs. To this end I was making the point that rider weight difference could easily be equivalent to. And that such weight would make little difference to times.

But 65lbs a different story. Where could this come from?
Starter motor, rear disc and some extra engine and perhaps gearbox weight (wouldn't amount to much I don't think).
What else is there to cause such an increase in weight?
My MkIII Riders Manual (original) quotes weight as 415 - 430 lbs. Don't know the reason for the 15lb possible variation but is WAY below your quoted 495lbs.
Someone has it very wrong.

Phil
 
1up3down said:
One other mention 1up,
Your reports stop in June 73, then pick up in 75, leaving out all previous 850's with the black box fitted.

there were two road tests of the Mark 2a with the black box, both did not run drag strip tests

Well they aren't much use in this discussion are they?
 
Time Warp said:
1up3down said:
One other mention 1up,
Your reports stop in June 73, then pick up in 75, leaving out all previous 850's with the black box fitted.

there were two road tests of the Mark 2a with the black box, both did not run drag strip tests

I believe they went from stop watches to calenders for black cap bikes.

My information says black caps, no performance difference.
Black box air box though was restrictive.

My MkIII BTW has neither, not that that is relevant to this discussion.
 
In Australia, road test point to point comparisons were far more practical.
The standard test required the riders to be in the pub, then run to their bikes, start them and go flat out for 1/4 mile.
The MkIII thrashed all other Commandos being nearly at the finish line before the others even got started.
 
tomspro said:
is there some kinda award for most posts on this forum in 2014?
:twisted:
ole Captain Ego tend to delute the overall content a bit, don't he?

Watch him respond to this as if we were actually talking about "him".
 
L.A.B. said:
1up3down said:
and the Mark3 at 495 ("curb" at 522)

According to the Mk3 manual the dry weights are:

Dry Weight includes battery, but not petrol, oil and tools
Roadster 465 lb. (211 kg) Interstate 475 lb. (215 kg).

The only reference to a "curb weight" (inc. half a tank of fuel) "of 522 lb." that I know of, is in the Cycle World Dec. '75 issue, (included in the 'Norton Commando Gold Portfolio' book) however that particular Mk3 was an Interstate fitted with a Vetter touring fairing, K & Q seat and crash bars.

L.A.B.
Yes, I just went and cross checked my workshop manual against the Riders Manual figures. Workshop manual same as yours, making them a lot closer to 1up's reference (don't know what that reference was). So we are getting some wildly varying figures from Norton themselves. I have a reference in a book somewhere which states the weight difference between the MkIII and earlier 850. That is what we are really after but I can't track down that figure as yet. But thinking logically and knowing what additional items came with the MkIII, something like 20-30 lbs max would/should see it out. I'll keep hunting.

Phil
 
The Rider's manual weights are the same as Haynes. I don't know why the big white workshop manual gives such a different number.

The weight shown as dry weight in the Rider's manual is about in line with the weight I measured.

Commando Quarter Mile Times (2014)




Commando Quarter Mile Times (2014)
 
Well they aren't much use in this discussion are they?

of course not, Phil, that is obvious

but since you made a point of asking, I felt I should give you an answer regardless if speed tested or not
 
by pete.v » Wed May 14, 2014 5:27 pm

tomspro wrote:
is there some kinda award for most posts on this forum in 2014?
:twisted:

ole Captain Ego tend to delute the overall content a bit, don't he?

Watch him respond to this as if we were actually talking about "him".

some people view internet forums as personal social media outlets and enjoy constantly commenting

Jerry Doe thoughtfully added the "ignore a poster" button to block any posts by an individual if ya can't stand em anymore
 
1up3down said:
Well they aren't much use in this discussion are they?

of course not, Phil, that is obvious

but since you made a point of asking, I felt I should give you an answer regardless if speed tested or not

That's fine. Shame they were not there though. They would shed some light on the slow MkIII standing quarter times looking at previous 850 times with black box and bean cans.
 
Getting back to the original post.....

There is a copy of an article from Classic Bike Guide on here, which is an interview with Norman White, ex-works lots of things....

Read it, it will tell you where and when he recorded 12.26 on a standard bike selected by the US dealer (who had complained to Norton that their advertised figures of under 13 secs could not be achieved), after selection it was taken out of the crate and run in...

It also tells how two local riders could not match his time.

The Baker Rawlins effort was sort of unnoficial 'factory'.....Rawlins was a works tester, but not paid for his exploits on the drag bike....also a great short circuit racer and all round nice guy....

Baker built the motor whilst an employee at Norton....I don't suppose he was paid to do it either, but I think he was also responsible for the service notes to do your home grown 850 Stage 1....

He also ported an ex Thruxton 750 Short Stroke head that came into my possession in late '75.
 
Just something I found on the net. Different weight figures again. It mentions standing quarter times so I think it is relevant to discussions in here.

Irony always accompanied the Norton Commando. Introduced in the late 1960s as a smooth and refined version of the traditional big British twin, its essential character was one dear to the heart of the enthusiast fond of the basic values in motor cycles. It was fast, lusty, lithe and light and virtues such as easy starting and quietness didn't fit into the conception.

The early 750 cc models were quick, with top speeds close to 120 mph and a combination of blinding acceleration and flexibility that has rarely been matched. Then the 828 cc models which were introduced in 1973 in an effort to improve reliability proved even better. They were tough, handled well and using Norton's patented rubber mountings for the engine and transmission were very smooth at high speed.

But the tough American noise regulations and a desire to appeal to a wider market spelled the end for the performance image. Three years later, the final form of the Commando, the Mark 3, appeared with electric starting, better comfort, disc brakes on both wheels and barely a whisper from the exhaust.

The irony was that when the Commando finally competed successfully against the Japanese competition in refinement, financial problems at the manufacturers, Norton-Villiers-Triumph, led to the end of its production in favour of the Triumph Trident, which was regarded as a more modern machine. The last Commando Mark 3 eight-fifties were completed in early 1977 while the Marston Road, Wolverhampton, factory was in the hands of the Official Receiver. The penalty that was paid for the civilized nature of those last Nortons was in acceleration. While the early Commandos weighed around 440 lb, the last Mark 3 versions tipped the scales at over 500 lb, enough to add a second to the standing quarter-mile times. With a time of 14-4 sec and a terminal speed of 90 mph it was little better than most 550 cc machines of the day.

The appeal of the Commando lay in its instant engine response. The layout of the engine and transmission with the 828 cc long-stroke parallel twin and separate four-speed gearbox was straight from the 1950s. Major differences were that the triplex chain primary drive had in the final form a tensioner and, as on the original Commandos, an all-metal diaphragm spring clutch.

The engine itself, with a bore and stroke of 77 mm by 89 mm, has a crankshaft with two roller main bearings and with a compression ratio of 8 to 1 was in a very soft state of tune. Developing 52 bhp at 6,000 rpm, it was as unobtrusive as an engine could be yet packed a punch from low revs that made the gearbox almost unnecessary.

The bike was still able to cruise comfortably and smoothly at 90 mph, but much of the old liveliness had been lost. Unlike the older eight-fifties, which would rev safely to over 7,000 rpm, the Mark 3 is at its best between 2,000 and 4,000 rpm. It pulls hard from 1,500 but beyond 6,000 the restrictive air intake and exhaust silencing cuts the power drastically. And there is no point at all in revving to 6,500 rpm.

Normally, such a lazy and relaxing type of power delivery makes a bike easy and undemanding to ride, and this is true up to a point on the Mark 3.

The four-speed gearbox complements the engine well and the drive is delightfully smooth, the rubber vane dampers in the rear wheel, added to ease the load on the gearbox, giving a snatch-free ride at no more than a walking pace in bottom gear. But the overall gearing is very high with a top gear ratio of 418 to 1. This, the optimum gearing for the engine, giving 6,000 rpm when the rider is flat on the tank at the top speed of 115 mph. At 70 mph, the unit is ticking over at a modest 3,800 rpm. The motor never feels that it is working hard, and there is never anything that could be called vibration at motorway cruising speeds.

However, the characteristics of the rubber engine mounting system made slow riding a chore. While the rubber units absorb the vibration at normal engine revs, an inescapable feature of the system is that it resonates at certain rev bands. On the Commando this is at 2,000 rpm. With the high gearing this occurs at 40 mph in top gear (a perfectly feasible speed for the torquey engine). The rider has to keep changing gear just to avoid the resonant vibrations. Fortunately the gear change is very good. None could be more creamy or positive in action, even though the lever has been transferred to the left-hand side of the bike.

Another poor aspect of town riding was a result of weak carburation, most obvious in throttle response where it showed as an occasional spit back through the two 30-mm choke Amal Concentric carburettors. The idling mixture control was near perfect, giving an excellent 500 rpm idling speed even after a brisk run; a period of slow running in town heated up the carbs enough to cause stalling. This was not the headache in traffic that it used to be just a touch of the green twistgrip-mouthed button and the electric starter spins the engine back into life.

It is not always like that - from cold, the Amal carbs still need messy flooding and the starter motor occasionally baulks at turning the engine over against compression without momentum from the crank's massive flywheel. And although we are assured of its normality, the crunching of the backfire-overload device when the engine stops sounds horrible. Such things are easily forgotten once you take the Commando for a cross-country spin. For like the Triumph Trident, the Norton Commando's handling is just great. The steering is neutral throughout the speed range and flicking into a bend needs no more than a nudge. Moreover, the bike feels absolutely secure when cranked over with the footrests lightly skimming the tarmac.

The other side of the coin is the poor ride quality of the stiff suspension. Small ripples are transmitted undiminished to the rider's hands and once caused the front wheel to step out in a bend. Only the bigger bumps are absorbed.

In this the Commando is no better and no worse than most contemporary bikes, although the deeper seat Norton use to absorb the bumps in fact spoils the comfort of the machine.

Without moving back the footrests to suit the long tank of the Interstate version (the test model), too much weight is placed on the rider's behind at speed and he wallows around on the padding. The seat cover is too thin, too, and under full acceleration the seat pan slipped and ripped through the material at the front.

Commando braking can be very good, especially now with the disc rear brake. The front brake lever is neatly curved to fit the hand and the power is immense. The rear unit was spoilt by an out-of-true disc and a leaking master cylinder.

Likewise the electrics of the bike are good with an exceptionally powerful 60-watt H4 quartz halogen headlamp offering a sharp pencil main beam and a well cut-off dip. The switchgear and controls are equal to anything on a Japanese machine. The clutch lever pull is light and smooth while all the necessary switches are in easy reach.

Maintenance has been eased on the latest 850, too, the most significant modification being the use of easily adjustable rubber engine/transmission mountings. Since the rear-wheel fork was mounted to the rear of the gearbox plates, excessive side play affected the handling adversely. This used to be adjusted for side clearance with steel shims - a very time-consuming job that brought criticism for the amount of attention it needed to keep the handling in trim. The final models used a much more sensible screw adjustment that requires the use of a small tool in the kit. It takes barely half an hour to set it up to taste, balancing vibrations from the transmission against handling quality.

The primary chain is adjusted automatically instead of moving the gearbox to tension the chain, and the rear wheel really is quickly detachable.

Overall fuel consumption averaged 44 mpg, but a tune-up and tappet adjustment (just like the old days) before the MIRA test session improved this to 51 mpg for the final tankful. Oil used improved to 700 mpp at 1,800 miles from new.

In its Manx Norton-type finish of silver with red and black lining, the Commando is as handsome as ever with plenty of polished alloy and chrome.

It is sad that production of the Commando was stopped so soon with such a loyal following of riders.

Road Test 1976
 
SteveA said:
Getting back to the original post.....

There is a copy of an article from Classic Bike Guide on here, which is an interview with Norman White, ex-works lots of things....

Read it, it will tell you where and when he recorded 12.26 on a standard bike selected by the US dealer (who had complained to Norton that their advertised figures of under 13 secs could not be achieved), after selection it was taken out of the crate and run in...

It also tells how two local riders could not match his time.

The Baker Rawlins effort was sort of unnoficial 'factory'.....Rawlins was a works tester, but not paid for his exploits on the drag bike....also a great short circuit racer and all round nice guy....

Baker built the motor whilst an employee at Norton....I don't suppose he was paid to do it either, but I think he was also responsible for the service notes to do your home grown 850 Stage 1....

He also ported an ex Thruxton 750 Short Stroke head that came into my possession in late '75.

Interesting that the two local riders were not as quick - raises a question about their level of experience in getting down to it ?
 
Isn't Norman White about the same size as a garden gnome? Might explain the times.
 
acotrel said:
What have drag strip times got to do with anything ? If you use the bike normally, you ride it around corners before you come to the straight bits. The speed down the straights is very dependent on the speed you are carrying around the corner and how soon you can safely get on the gas.

The S1/4 time may not have much to do with anything to you, but one thing that is engraved in my memory is the M Mech. Road test of the first Commando out in 1968 with the old Atlas engine and drum brakes is the 0- 60 time of 4.8 seconds :!:
That would beat the majority of race sports cars of the day in the rush hour traffic lights Grand Prix we get in the Northern hemisphere
That was a STOCK bike: but I think it might have been a carefully blueprinted engine :?:
 
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