certified quarter-mile time.

12 even , @ 114 . ppphhhhph .

http://www.classicbike.biz/Norton/Broch ... ochure.pdf

Mags below have cover NORTONS . F-750 . Hop up was in this mag too , dunno which month / year .Will tryn find it .


http://www.ebay.co.uk/itm/Motorcycle-Me ... 230ed07e78

http://www.ebay.co.uk/itm/1972-Jul-MOTO ... 4ab227dc32

Mohamed & the Mountain .

http://www.ebay.co.uk/itm/Motorcycle-Me ... 4cfcb8a935

ppphhhhph

http://www.ebay.co.uk/itm/MOTORCYCLE-ME ... 3f119285ad

At least they wernt all asleep back then .
 
All very impressive.............seems strange that the times posted by a factory prepared bike being raced by a good rider, are slower than those suggested by magazine tests of bikes which were supposedly stock?
 
[quote="Murray]
When I bought my Commando in 1975 the Combat problems were already ancient history and most bikes had already been corrected. The high-compression motor with its hot camshaft made the Combat the quickest stock Commandos of all the original bikes. They regularly ran the quarter in the low twelves. Bikes like my ’74 850 only ran in the low thirteens on a good day but could use regular fuel instead of premium. Comparing a Combat to an 850 is like comparing a hot Detroit made car of the sixties with an equivalent model from the mid-seventies. The earlier models could easily beat the later ones in every respect by a considerable margin. "

Note the link provided by Matt . It is an 850 which was used by Norton to run a 12 second flat 1/4 mile.

Also note the factory horsepower figure for the standard 850, 60 crankshaft hp at just 5900 RPM with California approved mufflers. Presumably a free flowing exhaust would give considerably more. More importantly, even with the restrictive exhaust, it makes 47 horsepower at just 4500 rpms. A lot of modern sport bikes do not produce this much power at such low revs.

http://www.classicbike.biz/Norton/Broch ... ochure.pdf
 
worntorn said:
Note the link provided by Matt . It is an 850 which was used by Norton to run a 12 second flat 1/4 mile.
Click to expand...

Thanks for the information but the bike does not seem to be stock. Note the text from the brochure,
“...tuned in accordance with Service Release M3/56 dated June, 1973...”

According to the NORTON VILLIERS CANADA LIMITED “Service Sheets” a type 56 is a “1973 - 850 Model Commando – High Performance Modification...”

See http://www.eurooldtimers.com/functions/get_file_manualy.php?id=3506

I could not find the type 56 Service Release but I did locate the type 73 which supercedes it. A type 73 is, “850 MODEL COMMANDO “STAGE ONE” HIGH PERFORMANCE MODIFICATIONS”. This service release involved installing an ‘SS’ camshaft and doing a “Cylinder head Conversion to Full Flow High Compression [10.0:1] Condition” among other things.

See http://www.eurooldtimers.com/functions/get_file_manualy.php?id=3496

I always wondered how an 850 “Combat” would have performed if they had made one and now I know. This still leaves the 750 Combat as the quickest stock Commando from back in those days.
 
"This still leaves the 750 Combat as the quickest stock Commando from back in those days."

Only one way to find out.
Where are you located? My 850 is running real strong right now., I'd love to give it a go: :D
 
Oddly, there has been no mention here of the Dunstall Norton 810, that all the performance lads back then were using ?

Kit'o'parts that bolted on an 810 alloy cylinder and pistons, with a performance cam etc.
Suitably geared, claimed 133 mph. Or, quite a fast quarter.

We haven't seen a 1/4 mile time for a Combat 750 in its prime, either.... ?
 
worntorn said:
Where are you located? My 850 is running real strong right now., I'd love to give it a go: :D
Click to expand...

My bike is also an 850, a 1974 model which I bought new in 1975. It has been a great and reliable bike but I always knew the stock 850s ran about a second slower than the stock 750 Combat in the quarter mile. It is too bad that Norton never offered a "Combat" type option for the 850 or ,at least, I don't remember them offering such an option from the factory.

P.S. If your bike is stock and you do find an improved Combat to race then prepare to receive your arse on a platter. It would be like putting a low-compression Dodge 440 up against a high-compression street-hemi. The 440 will generally always lose to the 426 .
 
September 72 Two Wheels Mag. ( Australia ) had a 750 Combat test . They used a drag strip & got entusiastic, so times were realistic . Havnt got it though , now .

The ' Stage ONE ' hot up was cpontinued through to ' Stage Three ' , Norvil spec ( Hemi /Dunstall ' big valve ' ) Head , 4S cam , Gears shifted closer ( 1st , 2nd ) .
With a 18 in KR 84 Dunlop for ridding of excess whell spin , I believe it was 10 . 5 sec .

Keep searching those service releases , thanks .
 
There was no Tuning Sheet 3.

Tuning Sheet 1 used a 4S cam, etc.
Sheet 2 was a pretty full-on performance motor.
Same as Dave Rawlins had - 143 mph (2 way average at Elvinton International meet) out of a stock looking Roadster. 11.5 sec 1/4, with a change of gearing.

As repeatedly mentioned here, Dennis Poore wanted a Combat spec 850, but it couldn't be built to meet noise regs. So the factory released Tuning Sheet 1, and Tuning Sheet 2.
 
Well WHERES the bleedy information . Please . Says ' 2S ' rthere old beane .

It IS the One D.Rawlins ' had ' . THAT was the ' Test Mule ' . pictures , pictures .
Intresting the Combat was higher (Engine ) spec than first P.R. almost , putting the Hemi non squisband (short stroke ) HEAD on the 850 , with the 4S cam ,
gets the 850 as a ' Stroked ' 750 s.s. :D :wink:
thisll do it

http://www.eurooldtimers.com/cze/manual ... racer.html

NOISE , thats NOT noise . , its MUSIC .

===========================================

http://commando.yolasite.com/performance-mods.php

' ONE ' will NOTICE 36 m.m. Carbs , down the bottom here . Being that Mk IIs flow a few mm over Mk Is , 32 Mk IIs on a later (beefed) 750 , Fancy treatment to the
valve mechanism ( attention ) along with a Mk III ' Tapered 32 to 30 port with the 1 5/8 Valve , will get the little booger stomping .Setting the 2S camshaft a trifle
early , will get a 4.000 to 7.000 powerband . The tapered port Now being regarded as the better cylinder filling .

This'll tear the balls of any two valve wobbler such as a Z1 , if you can stay on and steer it . Not that Simple .
 
What are we talking about here - I find your cryptic shorthand difficult to interpret as to meaning ?

The 750 pdf you link to has nothing to do with the 850 Tuning Sheets.
Different animal.
 
WOT .

" the Tech. Release on the Norvil Head 4S cam " THE WRITE UP . in motorcycle manias , & a few of the yankee comics also .
The one in M.M. was a bit of a page in the back somewhere . The ' CLYMER ' workshop manual has some of the info as a supplement in the rear .
 
.

P.S. If your bike is stock and you do find an improved Combat to race then prepare to receive your arse on a platter. It would be like putting a low-compression Dodge 440 up against a high-compression street-hemi. The 440 will generally always lose to the 426 .[/quote]


There is an exaggeration if ever I have seen one!
The 426 street hemi dynos an easy 500 to 515 hp.

A low compression 440 puts out 220-250 hp depending on model, less than half the power of the hemi.

According to the people who built our bikes and would have an inkling of reality, the Combat produced 65 crankshaft horsepower and 49 pounds torque, and it has to run up to a higher rpm to accomplish this.

The same people, and remember, they built them so they ought to know, tell us that their regular 850 model makes 60 hp at 5900 rpm using their new california approved restrictive mufflers. It also makes 56 foot pounds torque.

I think you have raised the Combat model to mythological status. I know all about this, i have Vincents!
 
)However , for the record . A steel crank 440 out of a motorhome ( or any of the rest ) Given a Cam , intake , large 4 BBL
and valve gear ( not a big spend ) will run 500 hp . Best value round for Horse Power .

We Suggest You follow the same course with youre 850s . :D 8) :lol: ( see info above :mrgreen:
 
Yep, but the comparison was between the 230 ish hp low tune 440 and a 500 hp 426, definitely an no contest kind of contest!
 
worntorn said:
.
According to the people who built our bikes and would have an inkling of reality, the Combat produced 65 crankshaft horsepower and 49 pounds torque, and it has to run up to a higher rpm to accomplish this.

The same people, and remember, they built them so they ought to know, tell us that their regular 850 model makes 60 hp at 5900 rpm using their new california approved restrictive mufflers. It also makes 56 foot pounds torque.

I think you have raised the Combat model to mythological status. I know all about this, i have Vincents!
Click to expand...

Some folks think that Nortons just didn't revise the horsepower figures downwards to where it should have been after the Combats demise, triumph of the Sales Dept over the Truth Dept ?

Those plastic aircleaners and blackcap mufflers were dog-slow compared to previous, so something happened. Other threads mention 45ish hp at the rear wheel, and less for the Mk3, where the Combat had more, in the low 50's, so maybe these numbers are more than just idle gossip ?

And then there were the Dunstall 810 boys, those things really flew = fast as a Z1 - until the cylinders lifted off the crankcases. Bring on the bolt-through 850 cylinders, for a reason....

Ever taken on an early Commando with your Vincent ?
Any Commando should do a Rapide, although a slow Commando might lose to a good Black Shadow ? On paper, anyway...
 
Well i have another Vincent tucked away that I bring out for special occasions. Its internals are all lightning spec.
It only has a couple of thousand miles on it since the resto, so I just recently got a chance to really exercise it. It is very quick.

The one in the Brake test video is at US Black Shadow spec. US Shadows were a touch higher compression than most other shadows due to the better quality fuel available in the US at the time.

I actually prefer to ride the one that is at Shadow spec, it has better midrange for pulling those long mountain grades loaded 2 up with luggage. It also has better brakes and is the easiest starter I have ever had.
The guys in England thought I had an estart on it because I can start it with a drop of the leg while my wife and I are seaed on the bike. Watching from the primary side it is tough to see any kick start motion.

http://www.cyclecanadaweb.com/articles/5442/ This is an article about our Vancouver Vincent group. The author ended up following me for a 150 miles or so on the way home, as he explains.

Oh and to answer the question, no I have not taken on any Commandos with the Vincent. In a Sprint, i think either one would be a bit much for a Commando, tho it might be close with the lower tuned bike. Out on the road and loaded pulling those big grades, the Shadow tuned Vincent would be the favourite, tho an 850 is also a nice torquey machine. Pretty sure the Vincent would reign supreme for that tho. Even climbing The damn thing will snick up from 60 to 90 mph, fully laden with two large people and gear, just in the time it takes to pass a semi. Kind of amazing really.


Glen
 
Matt Spencer said:
September 72 Two Wheels Mag. ( Australia ) had a 750 Combat test . They used a drag strip & got entusiastic, so times were realistic . Havnt got it though , now.
Click to expand...

Well, I hope they gave it a fair test compared to the very biased test by Cycle Magazine in 1973. 49.7 horsepower is obviously from the low-compression 750 and not the high-compression Combat.

worntorn said:
Yep, but the comparison was between the 230 ish hp low tune 440 and a 500 hp 426, definitely an no contest kind of contest!
Click to expand...

Comparing the low 8.5:1 compression 850 to the 10.0:1 compression Combat is similar to comparing the Dodge engines. The results at the drag strips were also no contest. Raising the compression increases the engines thermodynamic efficiency and changes the thermo chemistry by getting more Nitrogen involved in the reaction. The marketing horsepower and torque are irrelevant but the certified drag strip times are not. When did a stock 8.5:1 compression 850 ever run under 13 seconds in the quarter mile? The old 9.0:1 compression 750 often ran 12.70 on a good day and the Combats were faster still. The 850 just wasn't that quick.
 
Well yes, it woud be an apt analogy if the 850 was about as powerful as the old Model 7 Dommie, around 30 hp.

I dont think i can win the argument Murray, you have knowledge of these bikes that the makers didnt!

Here is one last road test for you to look at and denounce!

This one is a 12.75 et.

http://www.classicbike.biz/Norton/Mags/ ... -World.pdf
 
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