?A fast Norton?

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May 2, 2005
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Without another Norton nearby to go head to head with, I'll ask the question: How "fast" are other people's Nortons? My bike will put ~60mph on the clock in 4th at ~3800-4000rpm. I blast up to 70 is terrifying and I cant imagine doing 100 on my bike. This means that a CB750 will kick the snot out my Norton, and of course I won't accept that!

Going up mountain roads with a headwind is hard work for my bike and I'm just wondering if they all go like that? The facts: I have twin Amal 930's, electric ignition, stock everything else.
 
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Aug 20, 2005
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Check what gearbox sprocket you have gearing seems a bit low to me. 21 teeth is a good road sprocket. Mine (rough guess) is doing 70mph on 3800 rpm. Main thing with commando is torque, it has massive instant throttle resposne & can pull trees out of the forest from 2000 rpm. Cruising at 90 is a doddle, Top speed I dont know because I dont want to cain mine out of mechanical sympathy, but with chin on the tank 110 plus probably. Dont kid yourself, modern jap bikes 400cc upwards will run rings round it for speed any ride on the commando is way more satisfying. They also use far less petrol, insurance & spares are cheaper, consumables last longer.
 
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May 2, 2005
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Hey Geoff, Thanks for the reply. My gearing is 21 front 42 rear. At 90 my engine is around 5000 rpm. Not so easy for me since its so damn windy here im usually getting blown all over the road. 55 is a much more sensible cruising speed but im an accident waiting to happen going that slow on the highway.

The norton is much more fun than a modern jap rig for sure...and that counts for something.
 
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Oct 9, 2004
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Well, let's see... breaking in the new engine on George Dean's dyno I've got 59.7bhp @ 6600rpm and 48 lb/ft @ 5200rpm (corrected) at the rear wheel - or about 30% more than a stocker. Power's pretty flat between 4500 and 7k, torque's flat from 3600-6k, so it should be very streetable as well.

The bike tips the scales at 393lbs wet. I'm 160. The belt drive gears it more like a 23x42. Stock gearbox gearing. Slightly (1/2 inch) shorter rear tire.

Hmmm... I had to estimate the frontal area, but Desktop Dyno says 0-60mph in 3.6 sec , 1/4 mile in 12.1 sec @ 103mph. My guess is that it'll run out of gear before it runs out of power - so 130mph or so.

Plenty fast for me.

(George thinks it would pick up 3-5 hp with 35mm Keihin's. Not for $1500 dollars it won't! :lol: )
 
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Apr 7, 2004
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I pull 50 HP at the rear wheel on the dyno 44 lbs. Belt drive and a 20 tooth front. third gear to red line 6500 rpm gets the speedo reading 115 mph no faster in fourth gear. This same bike gave me 59 MPG at 55 mph on the way to Mid Ohio this summer. I can go 80MPH at 4250 RPM all day long. Get yourself a gps unit to run the right times. norbsa
 

MichaelB

"Sons of Arthritus"
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$1500.00 for Keihins!!!!!! I was quoted about 750.00 with cables and throttle. less manifolds direct from Sudco about a year ago.
 
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Dec 2, 2004
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? a fast norton

Mountain roads, that is about all I have. E-Bay a set of 36 Del'Orto pumpers and mount on Amal Mk II manifolds for a true high RPM rush with a 21 sprocket. Works a charm on a Combat with slight head modification or two. Also iidles at 750 RPM.

JT
 
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Oct 9, 2004
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Michael:

Thats what Matt at CNW wants for a jetted ready-to-run kit he's been working on. Its all inclusive and has all the necessary Norton bits.

He's got some time invested in getting them to work right, so I guess he's entitled. (Jus' not to my money.)

JT:

Tell me about them Dell'Orto's. Set up, jetting, etc. Much of a headache? How did they fit? What'd they come off of and how much did you pay for them?

Do tell.
 
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Aug 29, 2005
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if you are worried about what a cb750 will do when you are riding a norton then perhaps you should be riding a different brand of bike....a honda may be faster or quicker although i really doubt it...when you get into any bikes that have the power these do it is a matter of the riders capabilities more than the bikes....there has yet to be built a honda or any other make for that matter that comes anywhere near a norton in that undefinable quality of nice....go and enjoy the bike because it is a really nice bike...if ya gota have the fastest bike on the block there are plenty of them out there that will eat a norton for breakfast and then come back for lunch but none of them wil put a smile on your fae like a norton :wink: barry
 
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Jul 18, 2005
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I agree Nortons aren't about going fast but to address the Norton/CB issue that was brought up my friend has a 73 CB750 he's restored that's perfectly stock and I can take him easly with my stock 70 roadster.....and have a lot more fun doing it.
 
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Dec 2, 2004
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David, I kept fairly percise notes on any and all changes I made to various machines, mine and others, in dated steno notebooks, however it indeed required a bit of research, so here goes.
What you need is 1 PHF 36 BS
1 PHF 36 BD
F is small body w/accelpump
B is rubber mount
D is right hand
S is left hand

Find an early model non EPA version of the above, possibly off of a LeMans Guzzi. EPA versions have different mixture screws and can't be exchanged.
According to my notes, my last setup was
main jet 140
needle k 6(top clip)
idle jet 60 (1/2 turn out)
slide 60/3
K&N airfilter attached to v-stacks K&N # RU 1320
Central oil tank ala 'S" except for reversing battery/tank location, to make room for the Filters.

I usually tune backwards, main first, because it is easier to get that circuit right and it is the least important in everyday riding.. I guess if you have access to a dyno, which I never have had, it would be a treat.

I have used both Amal MkII and Molossi rubbers, the Molossi being easier to use; Amal MkII inlet manifolds, and some custom ones made by Syd's Cycle in St. pete., Fl.

I paid 270.00 in 1978 for one pair, pre e-bay.
This has been just a quick overview as I have to go, my son is playing in a football game this afternoon and I have to ride north into the mountains, what a shame!

Feliz, Where have you been, in the end it is all about speed and competition, it is the rush that keeps you young, in moderation, ofcourse.
JT
 

ILLF8ED

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how fast?

A similar vintage CB750 is no match for a Commando, at least my experience in 1973.

My '72 combat is well capable of +100mph indicated. Smiths is very optimistic. I'm using a 21T gearbox sprocket.

Dr David - coincidence with the numbers 12.1 sec 1/4 mile at 103mph. I did a run at Ontario Speedway in southern Cal in '73 with my first combat roadster. The result was that exactly. Can't prove it though as the strip ticket is long gone. Don't forget to take into account your own weight (mass) when calculating. That's another reason Commandos were faster 30 years ago - we weigh more now.
 
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Sep 27, 2005
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how fast?

Don't have any clocked speeds but had a couple of combats in the late 70's. My riding buddy had a new RD 400 that topped out about 110 which I believe was pretty accurate. He usually jumped me by my front to his rear wheel till 3rd gear. After that I seldom saw him. My speedo on both bikes would go silly right at 110 but the bikes kept getting up.
I was wondering about the "terror" from 60 to 70. Are your isolastics right? The rear end on one of mine would slap back & forth from around 60 up unless I was in a turn.
 
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May 2, 2005
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By terrifying I mean I could not hold a straight line to save my live. It wasnt the bike, it was this miserable Hawaiian weather ;-)

I'm planning on going to a 40T rear when I get to Cali but that's about it for speed. Nice to hear what guys are running as always.
 
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Apr 13, 2005
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Hey KATESCOTTAGEIOM, what needle jet did you use?
I'd like to compare the setting you used to what I used in my 900GTS Ducati with 36mm delortos'.(32mm stock).
Bill edwards 850 commando/combat.
 
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Aug 29, 2005
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dellortos? DELLORTOS? ok, since i have had a set of 36 pumpers waiting to go on either my 750 or 850 or even my kid's [son Mark ll] SR500 yamahoppie.....can anybody give me a lead on parts? preferrably in canada....are any of the mikuni jets useable in these[or kehinie]? and do the numbers correspond? what about manifolds? i have the clamp on type with the nylon insert gasket...i can machine up a straight flange setup if i can get something that will offset the things enough cuz they are a lot wider than the anals...what would the jetting be for a single carb on a norton using a mikuni manifold or on the sr500? i am also looking for sr500 bikes or parts if any of you canadian folks have some looking for a good home...this gives son Mk.ll a bit of experience with big singles and kickers before i cut him loose on the real thing.....there was a 1951 garden gate manx just [did not sell] on ebay from kingston ontario[barrys bike barn] it only made 12400usd out of a buyitnow of 25000usd and it did not make the reserve....kinda puts things back into perspective dont it? zzzzzzzzzzzzzzzz
 
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Dec 2, 2004
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111
fast norton

Edward, I am in Columbus Ohio so can not retrive that info. Will be up here for the next three weeks, but I believe it was a 269ab or 265.
jt
 
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Sep 27, 2005
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23
Weather

callow,
oh I gotcha now. Been quite a few of those days here on the east coast this year too. Gusty winds, bridges & oncoming traffic made me skip a few rides on the Bandit S.
Dr. Hillers speeds seem more like what I remember from the 750's.
Never had an 850 before so if I ever get it set up right I guess I will see.
schiz
 
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