Jack of all trades

I suggest most motorcycles are examples of 'jack of all trades and master of none',
From what I have read on this forum and my own experience, my opininion is the Norton Commando must be pretty good are what it does.
The discussions about the various models seems to indicate there was a progression towards more tractability and less top end power. Tuning a road bike to give better performance usually has a downside. I think Nigel uses his Commando for road racing. It is 920cc and has a 5 speed gear box. However I do not know if the higher 4 gears are close ratio,
One of the best incearses in performance I had with my Seeley 850, was when I installed the 4 speed close ratio gear cluster. The downside was it was too slow when starting-off from a stand-stil.
A lot depends on how you use your motorcycle. When I was a kid I usually only rode around inside towns. On a highway my Triumph 650 was strggling to maintain 60 MPH in rop gear. To pass a truck was always a problem because of the internal ratios in my gear box. If I changed back to 3rd, the motor used to rev much high and go nowhere fast. When you can change down with less increase in revs, you stay well up where the best torque is, so you accelerate faster.
I know that might sound strange, but the cam in my 850 motor is almost standard. With those timings and a normal exhaust system. the power band should be quite distivct. If you ride your Commando from a standstill in first gear, then change-up to second then hold the trotlle at about a third open, you should be able to feel where the cam starts to work, then as the revs rise there will probably be a slight surge - that point in the rev range is where you get the best acceleration.
Nigel's 5 speed gear box might be a very intelligent modification.
I was once told that 'if you have a toquey motor you do not need a close ratio gearbox'. The guy who said that was a skinflint.

My Norton is a delusional experiment.

You need money to burn if you want a 5-speed TTi gearbox. Probably money well spent if you have it to burn even on a street Norton.

The AMC box is functional, and I have no problems passing slower cars, trucks, or motorcyclists with a standard 4-speed and taller engine and final gearing riding my 750 not Commando Norton, but the AMC gearbox technology is really antiquated. The TTi gearbox seems almost plug and play as far as the internals are concerned. Mounting a TTI gearbox on some model Nortons is probably a challenge.

I don't think that much about what I have to do to ride a motorcycle. It just happens instinctively under typical riding scenarios. Sliding low side out of control I'm not really that good at though.

I am totally conditioned to ride in a certain way which I learned by crashing many times when I was a kid. When I finally got around to racing the Seeley 850, I was appalled by the Norton box. So I immediately bought a close ratio cluster for $700. Being an idiot, I did not think of using the Commando first gear with it, so it has always been a bit slow getting going in clutch-start races. But the joke is - if you rev a Coomando really high, it will jump away fast in any gear. I just don't like doing it.
Close ratio gears give much better performance. I would spend my money on that long before I would raise the comp. ratio or do anything else to the motor. The big steps you get as you come up through the standard box, make the bike much slower.
I use methanol fuel because it is easier to get the jetting right. However I suggest a Commando on petrol could be just as fast. It would just take more time and care to tune it.
The other thing is the taper on the needles. When you change up to a highr gear, the motor slows and the throttle moves up, and the taper on the needles start to have effect. With a bigger stepin the gearing, that happens quicker and the mixture richens quicker. A slightly too-rich mixture substantially slows the motor. I always use the leanest needles - slower taper. It is quicker.

Yes, I do have to keep the motor on the pipe with the widespread gear ratios when I shift if I want to actually go fast, whatever fast is. I'm over carbureted, but it does work surprisingly well.

Have to agree that spending my money on a better gearbox would have been a masterful use for it. A close ratio 5 speed probably would make riding more enjoyable.

Schwany said:

Yes, I do have to keep the motor on the pipe with the widespread gear ratios when I shift if I want to actually go fast, whatever fast is. I'm over carbureted, but it does work surprisingly well.

Have to agree that spending my money on a better gearbox would have been a masterful use for it. A close ratio 5 speed probably would make riding more enjoyable.

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I think my 2 into 1 exhaust systen and methanol fuel helps a bit. However the biggesr power boost cane from the close ratio box, and the leaning-off and shape of the needles in the carbs. After I crashed my 500cc Triton and carried a painful injury, I sold it to my mate who had built it and crashed it in the 1950s - for the current cost of ome of it's AJS7R drum brakes - $5000,
He brought it to Winton Raceway on a practice day. It was on petrol and had separate pipes with silencers. I grabbed it and had a ride on it. Even on petrol, it was fast enough to be competitive, and was almost sane. It still went sideways in one corner.
I think a lot of tuning stuff is bullshit. Even an unmodified motor can be tuned to be fast enough - especially a Commando motor. Over the years,I developed a rigorous systematic tuning process. I arbitraritly, set the ignition advance and comp. ratio - keep them constant and carefully tune the carbs.
Onr of my mates does the opposite - he tunes the carbs with an oxygen probe, then advances the ignition while the bike is on a dyno, until he gets maximim torque. His way might be even better,
When you do this stuff and ride the bike, you become conscious of the power characteristics. But if you gain more torque with a Commando engine, you usually do notb know it until you raise the overall gearing.
With the Commando motor, high overall gearing and close ratios give maximum acceleration - make the heavy crank help you. A race-change up through the gears gets my 850 really going.
It has actually surprised me because it should not because it should not be able to do what it does,
You might believe I am bullshitting-on, but I probably do know what I am talking about.
My old mate Allan Greening was with me the last few times I raced. He was standing with my wife the last time, when I rode under and passed the 3 leaders about 20 MPH faster, apparently he got all excited. Sadly he has since died, so cannot help me race again.
My wife has put the kybosh on my racing, but two weeks ago I had the cataract removed from my left eye, and the right eye will probably be fixed in ten months time.

I really have to ride the bike again, even if only on a ride day. I want to do an on-board video for my brother and my grand-kids. It is still sitting with it's transmission in bits, but I am slowly getting mentally better. At least I can now think about racing again.

Some simple facts: For acceleration what matters isn't engine torque but torque at rear wheel. At any speed best acceleration is when gearing matches top horsepower rpm.
When I raced speedway JAWAs without gearbox the idea is to have enough wheel spin to keep engine pull strong. Always changing engine and rear wheel chain wheels to match the actual track.
When roadracing fairings became common in the late fifties, top speed increased about 10 MPH. Adjusting overall gearing to match meant that first gear became higher too, impairing acceleration from standstill and you had to slip clutch in hairpins. So a lower fifth gear and later a sixth gear was needed.
Usable power band depends on cam timing and other engine set up. My Manx and RDLC are dead below 6000 and tops 8000. The CB250 and the little everyday Ninja works best between 9000 and 12000.
Friends who races 50cc which has a very narrow power band has 8 gears.
When I designed 5 speed gearboxes for sidecar racers, I made a simple sawtooth diagram of speed versus rpm. Angle of lines to match gear ratio. vertical lines to find rev drop on upchange.
As air resistance increases at speed you need more closely spaced gears at high speed. The outfit racer wanted max rev drop between 4th and 5th to be 700 rpm. Or maybe 900? Don't remember.
When I fitted a 5 speed TTI box to the Manx, I ordered it with a lower first. Then got nice gear spacing progressively closer at higher gears. Their 6 speed ones have not so good spacing.
Even with the lower first the Manx needs clutch slipping in the pit. Once on the track it works great.
On wide ratios and close ratios. If revs drops too much when shifting up, ratio is too wide. Depends on engine tune.
Once had a road going Gold Star with close ratio gearbox. Completely useless in traffic.
Remember when cars first got 5 speed transmissions? A very high 5th that improved fuel consumption but lousy acceleration and need to shift down uphill.

When data is multivariate, cause and effect can be established through pattern recognition. Changing only one variable usually does not achieve much,. When kids go to university to get a better job, it is usually abiut the rates of pay, and not a geuine interest in achieving anything other than becoming wealthy. Money-motivation is a curse. on society. Our whole global system is bult upon gambling. Most money exists as debt We borrow to gamble. Sounds like sin to me.

In motorcycle road racing, there are two predominant patterns
Fast down the straights but slower in the corners.
Slower down the straights but faster in the corners.
An increase in horse power is always good, But a Commando 850 is usually faster in corners than any TZ350. What you lose on the merry-go-round, you can pick-up on the hurdy-gurdy. Never have a victim's mindset when you get blown to the weeds halfway down a straight.

We are all programmed to think in certain ways. Life is just a game like any other - be systematic.

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If it rains when I am racing, I am always in with a chance. I usually speed up relative to the other guys, If you crash in the rain, it usually does not hurt as much.