Commando Quarter Mile Times (2014)

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I have a book titled Norton Commando Ultimate Portfolio by Brooklands Books.

This book is devoted purely to road tests of the various Commandos from 1968-1977.



These are STOCK bikes:


August 1968 Cycle World Norton Commando 750 13.47 seconds at 96.35 mph

September 1969 Cycle Norton Commando S 13.18 seconds at 101.69 top speed tested 110mph

December 1969 Motorcycle Mechanics Commando S 13.4 seconds at 102

March 1971 Cycle World Commando 750 Fastback 13.11 at 101.67 top speed 116mph at 7380rpm

March 1971 Cycle Commando 750 Roadster 13.01 at 102.16 top speed 110

September 1972 Cycle World Commando 850 Interstate 12.96 at 102.38 top speed 116

September 1972 Cycle Guide Commando 750 COMBAT Roadster 13.09 at 103.68 top speed tested 109.5

June 1973 Cycle Commando 850 Roadster 13.06 at 100.78 actual top speed not tested

June 1973 Motorcycle Mechanics Commando 850 Roadster 12.9 quarter mile, no top speed tested

November 1975 Motorcycling Monthly Commando 850 MARK 3 15.0 at 88mph


As you can see there is really very little difference in quarter miles times, most around 13 and that includes standard 750s, Combats, and 850s, only the much heavier Mark3 was significantly slower

There ARE other tests that show for example an 850 with a 12.2 quarter mile, the fastest I am aware of
but I don't have that test and so can't confirm if the bike was totally stock or not, anyone have this?
 
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I seem to distantly recall MCM magazine mentioning that the secret to really fast times on the 850 was to get the rear wheel spinning off the start line,
until it hooked up and went. - "like a proper drag bike".

Its also worth repeating, as discussed here before, that Norton Villiers had a FACTORY hot-rod 850
that was capable of some really fast 1/4 mile times, and top speed runs. Circa 1973.
This was effectively a Combat 850 prototype, with the 1st ever 4S cam.
The name of Baker and Rawlins were involved.
Can't help thinking this is involved here somewhere in those times mentioned ?
(Combat 850 never came to production, would not have passed the noise tests)
(And of course, NV had already been burned, badly, with Combats !)

I also have those reprinted tests.
Its worth commenting that that is not every Norton test reprinted, there are quite a few others.
Whether that is significant or not....
 
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Its worth commenting that that is not every Norton test reprinted, there are quite a few others.

true, Rohan

the book I have also has road tests and speed results on the Dunstall 810 and the Production Racer but I did not not show those results because those were obviously not stock bikes

in addition, there were a couple more road tests that did not bother with speed testing, just general reporting
 
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The Mk3 was slow because it came with a very quiet , stuffed up stock exhaust. Someone at NV decided the Commando should be whisper quiet to improve sales.
Change to a free flowing exhaust and then all is the same as the earlier bikes, other than the weight of the starter mechanism, which at about 20 pounds won't make a big difference, maybe a tenth or two.
Quiet exhuasts, unfortunately, always kill power bigtime., especially at the top.

Glen
 
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worntorn said:
Someone at NV decided the Commando should be whisper quiet to improve sales.

Actually, it was to meet noise regulations.

Somewhere earlier, (early 850 models ?)it had been necessary to raise 2nd gear ratio in the gearbox to meet noise regs a few years earlier.
The noise tests were done flat out in 2nd gear.
By raising 2nd gear ratio slightly, it passed !!

Oiling the chain before the noise test reportedly also reduces the noise by at least 1 dBa.
And gives an extra pony or 2 on a dyno test too...
 
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true, Glen

in addition to the exhausts the air box was more restrictive to again meet the decibel regulations

although the Combat was justifiably plagued by main bearing failures, it was not alone in being signaled out because the Mark3s suffered from a spate of quite soft cams, some that needed replacement at only 6K miles
 
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worntorn said:
Quiet exhuasts, unfortunately, always kill power bigtime., especially at the top.

That explains all these HDs with no mufflers, that sound like they are going fast.

A stopwatch tells otherwise though ??
 
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1up3down said:
true, Glen

in addition to the exhausts the air box was more restrictive to again meet the decibel regulations

although the Combat was justifiably plagued by main bearing failures, it was not alone in being signaled out because the Mark3s suffered from a spate of quite soft cams, some that needed replacement at only 6K miles

So what happened to your "much heavier" earlier statement that this was the reason for the slow 1/4 times by the MkIII?
Can you advise your reference material about the soft cams? Not on topic but you have raised it in here.

Phil
 

tomspro

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Among the many factors effecting quarter mile times, and especially top speed, seems to me GEARING might be the most relevant.
Final gear ratios were changed many times over the years, and I suspect this accounts for much of the differences listed.
 
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So what happened to your "much heavier" earlier statement that this was the reason for the slow 1/4 times by the MkIII?
Can you advise your reference material about the soft cams? Not on topic but you have raised it in here.

Phil


you are asking for a reference for the Mark3 soft cam statement, Phil?

here you go:

December 1975 Motorcycling Monthly "Norton Commando Mk3-The Inside Story"
 
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I've described here before the amount of work required when a silencer (muffler to you 'mercins) is changed. I don't believe anyone, let alone NV in the 70s would design, develop, test a new silencer on a whim. There would always be a new rule/regulation to be met. I know that when I was there (Sept 69 to Nov 70) nothing was entertained that would actually reduce performance. I was also told by the head of the Development Department, that a road going fourstroke was far harder to silence to meet any regulations than a two stroke, all to do with mechanical racket rather than pure exhaust noise.
Again it may come as a surprise to those from the former colonies that 1/4mile times were pretty much "what you got" after the bike had been "optimised" for other criteria like top speed, cruising speed, fuel economy etc etc.
I'm still amazed that HD can appear to get away with what they get away with.
cheers
wakeup
 

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wakeup said:
I'm still amazed that HD can appear to get away with what they get away with.
cheers
wakeup
It's a matter of pride, albeit arguably misdirected. HD is one of the older manufacturers around, they're employee owned, and they're made in America (the Mid-West, no less). While I'm not offering this as an excuse, understand that there's a lot of home pride surrounding the HD marquee. Unfortunately, this also tends to cultivate a considerable amount of arrogance. It's because of this attitude of most HD owners that I've chosen to distance myself from their world over here. They really tend to snub their noses at you. That, and the antiquated design, the rear cylinder is mounted backwards so it has to be fed extra fuel just to keep it from going into melt-down, the split rod design that likes to toss its cookies at anything over 5000 rpm, everything HD-related is at least 50% more expensive than it should be...

I met a Harley owner who joked that HD stands for "Hundred Dollars", since that's what's constantly flowing out of his hands to the bike shop. 'Nuf said.

Nathan
 
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in addition to the exhausts the air box was more restrictive to again meet the decibel regulations

But the rubber snorkel inlets to the plastic box were removable and have disappeared from most Black plastic air boxes, leaving big holes behind so I doubt the airbox is now restrictive.
 
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All factory Commandos are mostly just fragile dangerous underpowered quaint antiques to me and general bad boy HD bunch everywhere, many remembering their start in cycling on British bikes and Commandos themselves to know the facts. Still a Brit bike can get ya let into HD only parties but of course not many proper BI bikers would be seen at such nasty loud events. To be invited to ride and join in with the HD hog guys that show off running two abreast through tights at breakneck speeds and just need to nail throttle a bit more to spin rear w/o wheelie or brakes requires Norton performance beyond factory issued capacity. If ya think the 1%'s picked a wimpy sloppy handling breed, dare ya to allude to that before leaving with them. It does take a mean mannered mood to get the most out of a drag test against another with every possibility to blow up crash or get beat. If ya can pull it off though the highs will never leave ya.

1200 drag only Sportster on its wheelie bar in near lane. Not his leg out back, light track shoe toe is on rear set peg. Best launches gotten by clutch drop spinning rear to wheelie pass 6800 peak power before the X-mass tree.
39321424AdGaOv_fs_zpse79e2499.jpg
 
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1up3down said:
So what happened to your "much heavier" earlier statement that this was the reason for the slow 1/4 times by the MkIII?
Can you advise your reference material about the soft cams? Not on topic but you have raised it in here.

Phil


you are asking for a reference for the Mark3 soft cam statement, Phil?

here you go:

December 1975 Motorcycling Monthly "Norton Commando Mk3-The Inside Story"

Yes I was asking, as per my post which you have quoted. Thanks for this information.
The MkIII certainly wasn't perfect, there were issues (of its own) with it just like every other Commando had suffered one way or another. Impending regulations required the swapping of gear lever and rear brake, no big issue for a rider. Electric starters were now the norm. Norton's was pathetic. Bean cans and black box actually came out in Sept 73 in Europe. Bean cans had no effect on performance but black box certainly did.

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

So we are looking elsewhere for this slow performance. Standing quarter times was an obsession in the early to mid seventies in the motorcycle world until it occurred to someone that melting tyres and burning out clutches was not everyday riding technique and so useable power became more of interest. Not the need to have to change down all the time for a hill, for example, as required by some Japanese bikes. The Commando (all Commandos) was very high up on these measurements. Lots of torque.
In 1973, standing quarter times could virtually sell a new bike. Many of those who read them and bought a Kawasaki MachIII, later wished they had never seen the report.
 
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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.
 
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While thread is hot can anyone find records of US National drag bike events in '68 to '77 that list single engine machines and times?
 
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Ran across this.
http://www.musclecarclub.com/musclecars ... fast.shtml
Except for the 427 Cobra, which you can argue wasn't a true Detroit assembly line product, the Commando was running in the same neighborhood as the hottest of the muscle cars. Especially by 1972 when US auto manufactures had generally dropped compression ratios across the board.
 
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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
 
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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
 
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