certified quarter-mile time.

Have a quick Google Matt............always useful if you are not quite sure about info relating to older bikes!

Carbonfibre said:

Have a quick Google Matt............always useful if you are not quite sure about info relating to older bikes!

Click to expand...

The problem with googling anything is that the internet is inhabited by people who have appointed themselves as experts & state "facts" which are really nothing more than their own biased opinion.

Ian

Exactly right............posts on here about Nortons that run 12s 1/4 miles, and have 140mph top end speed seem to fall into that category!

Matt seems to unaware of the fact that the Rudge Four was in fact fitted with a four valve head, and I think Google might be able to assist him with accurate info relating to this, but not so sure about the Rudge Four having a 120mph top speed, or any other of the sort of claims coomon on here?

Balderdash :roll: , check youre miss quotes . :lol:

Id had access to the largest libary of automotive and engineerring books in the country , early 90s , and used the time I had
reading them , seeing it was the National ' Stack ' I wasnt burdened with suffering the Oriental innadequaceys .



Essentially you can see that the mass production engendered by the industryalists / WW II stuffed the evolution of motorcycles completely .Allong with ' regulators ' defineing the course of development .Honda was 50 years behind
with their V-4s , and never got round to superchargeing it .

A machine set up specifically for or with a top speed matching that attained at the quater mile mark is obviously
going to have major inadequaceys as a touring or performance mount . It stands to figure .

The significance of the quater mile other than as a mark on the road is little in comparison to the distant horizon .

Essentially you can see that the mass production engendered by the industryalists / WW II stuffed the evolution of motorcycles completely .Allong with ' regulators ' defineing the course of development .Honda was 50 years behind
with their V-4s , and never got round to superchargeing it .

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If ya look into the early Japan industrial foreign financiers you find 1st the Wall Street bankster bunch then 2nd the City of London bankster bunch. Its an additional factor along with each companies on shooting selves in their own tires. It took about 30 yr to earse Made in Japan as crappy fast used up then thrown away. Transitor pocket radios were a new thing Japan pretty much dominated market with and enjoyed that cheap wonder low fidelity music.

Harley is about as close as a Brit Iron bike as ever was outside England that still around, look at their evolution and what after market race buiders do with em to smoke even hopped up Asians in the sprints.

[video]http://www.youtube.com/watch?v=uNygpSJPLL0&feature=related[/video]

This is why im saying Norton ( ! ? , Me !? ) needs to do a ' real bike ' , Just looked at a stinkley bonnerfull . ASIAN . ' production engineering '

H.D. had the nous to get porshe to do a ' once over ' and appraisal of the funny thing , as to its durability and longivity / maintanance .The old Tutonic Logic bit .

Theres a precident for getting the best of the latest kubble wagon . Pre both WW I & WWII it was arranged so hostilities would commence immediatly after the international Grand Prix .
Fairly devious no doubt . They therefore detained the Grand Prix Mercedes and Rolls Royce dismantled , inspected and analysed the latest wonderous most advanced engineering no how.

The 2/5 Merc in fact has a Cosworth top end , ( :lol: ) so is British ( obsession and medling ) ANYHOW . For some 150 mph two up highway chariot , the displacement & output would be the minimum .

If theyd have the brains to keep the transmission as a seperate entity , the stability , sevicability and usefullness could be enhanced , You could run Sawbenches or Waterpumps & powerstations off of it . :wink:

Matt Spencer said:

This is why im saying Norton ( ! ? , Me !? ) needs to do a ' real bike ' , Just looked at a stinkley bonnerfull . ASIAN . ' production engineering '

H.D. had the nous to get porshe to do a ' once over ' and appraisal of the funny thing , as to its durability and longivity / maintanance .The old Tutonic Logic bit .

Theres a precident for getting the best of the latest kubble wagon . Pre both WW I & WWII it was arranged so hostilities would commence immediatly after the international Grand Prix .
Fairly devious no doubt . They therefore detained the Grand Prix Mercedes and Rolls Royce dismantled , inspected and analysed the latest wonderous most advanced engineering no how.

The 2/5 Merc in fact has a Cosworth top end , ( :lol: ) so is British ( obsession and medling ) ANYHOW . For some 150 mph two up highway chariot , the displacement & output would be the minimum .

If theyd have the brains to keep the transmission as a seperate entity , the stability , sevicability and usefullness could be enhanced , You could run Sawbenches or Waterpumps & powerstations off of it . :wink:

Click to expand...

Matt I wonder if you were a pro cycle racer, whether or not you would chose to use a penny farthing in the Tour de France?

Theres a Thing , I hadnt thought of that ;
Obviously , :wink: Putting a Z1 Engine in a penny farthing could well be the way to improve it .
They were so desperate , theyd try anything back then .

However , The Gestapo isnt that popuar of late ,
If you ask a stupid question , you get a stupid answer .

Why dont you answer the question Matt? You seem to feel that penny farthing technology is superior to that which came later, so surely you would opt for old style technology if you were competing in a cycle race?

batrider said:

But there was no Combat anymore in 1973.

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According to the NOC the improved Combat engines were available in 1973 for part of the year at least. Once the problems with the engine were discovered the factory took their existing Combat engine inventory and rebuilt them with improved parts. These improved engines were available in 1973 as I understant it.

hobot said:

...Maybe someone can find the American drag race organization records for late 60's if they exist online as I've always wanted some evidence beyond my own seat of the pants that my first 750 Norton ran 1/4 mile in 10.49 sec with a drag slick. It was not a Commando nor with near a Cdo's massiveness...

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Well, hobot, I believe you since Nortons and H-Ds dominated the strips back in those days. It seems to me there was a Norton engined bike called "Hog Killer" which really indicates the main competitors back in those days.

Matt Spencer said:

...Norton at two thirds the weight would do it @ 60 horse with a Slick aft ...

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The strange thing here, Matt, is that horspower to weight ratio is part of any racing fan's 101 course but our trolls do not seem to grasp even this simple concept. Not only is there a generational difference in the posts but there may be a gender one as well. It seems pointless to depreciate brands that ceased to exist over thirty years ago and yet the trolls are putting a great deal of time into their efforts. Perhaps this is more about attacking the site than about attacking the Commando.

worntorn said:

Maybe you are expecting too much from the poor old Combat. A skim off the head can only do so much, especially if the port alterations are done badly.

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The Combats were new for '72 and by '73 the weaknesses had been corrected. There is no way that a good Combat should not be quicker than a stock Commando with the standard engine. There was something very wrong with Cycle magazine's '73 test.

It is my understanding that there are several evolutionary models in between a Penny Farthing and a current generation Tour De France racing bicycle (I may even own one, a 10-speed Triumph "English Racer").

I wonder why none of those intermediate models are ever mentioned in comparisons and criticisms?

But there was no Combat anymore in 1973.

Click to expand...

Murray B said:

According to the NOC the improved Combat engines were available in 1973 for part of the year at least. Once the problems with the engine were discovered the factory took their existing Combat engine inventory and rebuilt them with improved parts. These improved engines were available in 1973 as I understant it.

Click to expand...

If you read up on your Norton engines, the 750's built in 1973 were not built to Combat spec, and were referred to as Mk 5 (or Mk V). They no longer had shaved heads to give higher compression, and without pulling out the books, no performance cam fitted either....? hth.

This is really basic stuff, any Norton history book gives this info...

I think youll find it depends on which information you acces , rohan .

Stock Inventory would dictate production to a extent , Sure they may have no longer planed quite as much of the heads ,
Cams , if know to be duff ( soft / poor heat treatment ) could be sensibly discarded .

Basically a specification is set , pre production run ( X - units ) and adhered to unless known cause to vary .
Most Catalouges " Specifications may vary & without notice " disclaimer is to cover such events .

however , I think youll find each batch or series would have Jigs and tooling set , so more than one specification over
the 1973 manufactureing period is likely assured .( i.e. no two batches would be identical specification, if seperate)
Likelyhood of finding good workman must have been irksome . Meridan stuff ALL had errors on inspection, pre coustomer here . And they purported to be ' entusiasts Loveingly building them ' .
As for books and magazines , half of that written , particularly in regard to opions of design features is ranting of ill
informed untrained jouranlists . Good copy , ? perhaps . But far from fact or accuracy .

Matt Spencer said:

But far from fact or accuracy.

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Well, Matt we do not have any books specified by the trolls but there are some books that do mention improved Combat engines.

In Roy Bacon's "Norton Commando - All Models" starting on page 35:

"The 1972 engine...was also available built to a higher degree of tune...called the Combat...option for the Roadster and Interstate. The extra power came from a raised compression ratio...hot camshaft and larger carburettors. The block was painted black...very short main bearing life...Norton...dismantled...engines went back and forth between Andover and Wolverhampton. All engines had the new mains...left the high compression ratio on the Combat...no way of replacing the 1mm that had been machined off..."

In the Norton Owners Club's "Commando Service Notes" they even provide a photo of one with the caption, "One of the most popular, the 750 Interstate 1973, with Combat engine, signified by black barrels. Photo credit: Motor Cycle"

Notes posted at
http://archives.jampot.dk/Book/Workshop ... _Notes.pdf

So there is little doubt that at least some Combats were sold in 1973 and there is no reliable source that shows they had their compression reduced or their hot camshafts removed.

Combats / 1973 .

Combats . Full stop . , o.k. the notes I had , mayhave / must have / parrallel reality ! / :shock: :?: :wink:

Had mention of " Case / Oilway / Drill 1/4 posn , oil pick up "/ cases . Definately took to it , preume NOC info .

Had mention off " Rocker feed pipes / plastic / melt / oops etc " " USE Nylon Hi Temp " ,

also mention of " two of our . . . 100.000 Miles , on rings ? / Bores / pistons . AIR FILTRATION Tips "

cant find these referances in that or the NOC internet , so , this is annoying , and could be bewildering .
The Combat cam wasnt unknown to Norton , as was the early P.R. camshaft . Apparently the Lifter hight
could cause scrapeing / interfearance on a few . i.e. the Cam pushed the lifters higher than they were Free to Travel .
Exasservated if no Base gasket installed .

So soft etc Cams , that , Mains ,& Valve spring Lift / Clearancing were the initial ' production ' Issues on Some .

Presumably rectified in production through the second production run . Thereafter , I Believe ( from My recall )
they were a bit carefull who they let have them , and ' Phased Out ' rather than discontiued them .

i.e. in ' production line ' terms the specification was superceeded , then bacame obsolette . Not Utilised ,
However finished parts would have to have been utilised or returned to stores ( Spares ) Thereafter
Machineing of castings may have been to altered specifications / tool settings .

With , what they called " The Mk 5 " the Combat had been superceeded .
Presumably , untill then , you could ORDER a ' Combat 750 '.

With the perception that Ducati production lines then worked on a similar ' keep the line moveing ' principal
ad hoc variations were , in that era , bound to occur . Even if just from batch to batch of components .

Tecnically , a 73 Combat is without the Magneto Blanking plate , according to the Californian site .
so appears simple , :lol: to identify .IF Original , 32 mm Carbs , Disc , Interstae 750 = ' Combat ' maybe . :lol:

Its 1974 Im worried About . ( just kidding ) Frame tag gives build date , so we need a ' Cut off ' date ,
Though again , depending on WHO , a dealer Order for ' Combats ' may well have been supplied
from current stocks , or Assembled from Current Components .

Which all tells us nothing really , or S.F.A. , Bar ' theres a later more detailed N.o.C. notes , or they wrote a differant one , just for me . :lol:

Murray B said:

Matt Spencer said:

But far from fact or accuracy.

Click to expand...

Well, Matt we do not have any books specified by the trolls but there are some books that do mention improved Combat engines.

In Roy Bacon's "Norton Commando - All Models" starting on page 35:

"The 1972 engine...was also available built to a higher degree of tune...called the Combat...option for the Roadster and Interstate. The extra power came from a raised compression ratio...hot camshaft and larger carburettors. The block was painted black...very short main bearing life...Norton...dismantled...engines went back and forth between Andover and Wolverhampton. All engines had the new mains...left the high compression ratio on the Combat...no way of replacing the 1mm that had been machined off..."

In the Norton Owners Club's "Commando Service Notes" they even provide a photo of one with the caption, "One of the most popular, the 750 Interstate 1973, with Combat engine, signified by black barrels. Photo credit: Motor Cycle"

Notes posted at
http://archives.jampot.dk/Book/Workshop ... _Notes.pdf

So there is little doubt that at least some Combats were sold in 1973 and there is no reliable source that shows they had their compression reduced or their hot camshafts removed.

Click to expand...

Was the "improved" Combat motor the one which did 6000 rather than 3000 miles before needing a rebuild? Trying to tweak the Norton motor so it could live with far quicker bikes like the H1/H2 Kawasaki's, was a very good example of the abysmally poor management of the Brit motorcycle industry in the 70s, as it cost Norton a great deal of money, and provided a lot of bad press related to the major mechanical problems.

"The last of the 750 series, the MkV was produced from November 1972 to mid-1973 as a 1973 model and featured improved crank bearings and the standard grind camshaft. Compression was reduced to 9.4:1 "

No Combats in 1973.

So the first run of those is preumably ' Combat ' castings , machined to ' Mk V ' specs .
Though a ' Combat ' may not be listed , Id think were still ' Supplied to Order ' , to more respected dealers .

The issues with Kamakazi kawsakis were more the reason , that ' a low profile ' was adopted .
Once the problems were identified , the fixes were applied in short order . SUBJECT TO AVAILABLITY .

My 70 / 71 had torn out the mains at 7.000 Miles , which was the recognised ' Combat ' Ball Race life . ! :shock: :lol:

Superblends wernt inexpensive . Dunstalls HD bearings caused shaft problems . Essentially they HAVE to sell at a profit for Continuity . Better wouldve been to up the price significantly ( and Fire All the slack workers ) & raise the pay of the ones who knew what they were doing .Wouldve saved a lot of money , long term .

Rohan , look up ' Evan Green ' = supercar scare .

http://v8racecar.wordpress.com/the-1972-supercar-scare/

Vivid Imagination ? Industrial Espionage and PARANOIA personafied , My P-38 was a 4 wheel ' Commando ' ,
springs , swaybars , dual Ex , Rover Vandenplas headers & covers , Holley . Dunno what the Honda was ,
equal or superior cornering in mountains to a 1000 / 1100 white whizz bang , better power transferance out of the twisties .
http://allsuburbs.com/clubs&org/leyland ... /targa.htm
( I built the thing , mustve just been my superrior skills & driveing :shock: :lol: :roll: :wink: )

But this is a p.o.s. & Lemon , according to popular belief . 1/2 Build Time to GM & Ford had them BRICKING ,ESPIONAGE
at ALL levels , Unions Particularly & G.M. particularly ( Theyd sold the Engine Design to Rover ) had a meanacing effect .

Repco Brabham ( F1 world Champ ) and Traco Oldsmobile are derivitives .

This is sheer delusion tho , like a certain cretains inteligance , reason , and logic . ???

http://www.youtube.com/watch?v=sXOlKqh2UXo
Would somebody care to explain this please . :mrgreen:

Matt Spencer said:

Though a ' Combat ' may not be listed , Id think were still ' Supplied to Order ' , to more respected dealers.

Click to expand...

The 1973 Combat is a known but fairly rare type but it does make sense that they were still available in that year. Norton chose to correct the Combat engines in inventory instead of paying the dealers to do it in the field. This took time and it is likely that some were still in inventory when the model year changed. It is no surprise that some Combat engines were fitted to bikes with 1973 stamped on their identity plates but I have no idea how the factory would record it.

Another engine available in 1973 was the low 8.5:1 compression 750. This one made less power than the standard 9.0:1 compresson engine and is most likely what Cycle magazine tested in 1973. This would explain why the bike ran so slow compared to the others.