MkIII Gearbox

I read a test report recently (can't remember where) by some know it all dick who was loaned a MkIII for testing. I had a feeling it was a recent test but not sure, I have read a lot of stuff on MkIII's having never before owned or ridden one so lost track.

He criticised everything, more about Commandos than MkIII's in particular. But he commented that the one redeeming feature of the Commando, the AMC gearbox had been ruined by swapping the gear change lever to the left. Made it feel like a mush bowl he claimed.

What bullshit! My gearbox feels as nice as any Norton gearbox I have used and if anything, the long gear change movement may be even shorter. On a good day, neutral is as easy to find as wombats on Joadja road. Also, a little green light goes bing "you are here sir".

So I don't know what the whacker is talking about. I don't know if ratios were changed at all for the MkIII, I haven't yet researched it. First to second could perhaps be a little closer but more going down than up. Torque covers up. Second is sometimes just a bit tall in a rolling turn at an intersection, with first being fractionally too low. But that was always a Commando trait in my opinion.

I would never want a five speed box, not for street use. It is something of a modern luxury to be on a bike with so few gears as opposed to thrashing backwards and forwards with six gears, as per modern trend, never knowing what one you are in or should be. My Beemer told me on the dash, and you needed it!

The tester was a claimed authority of some sort. Just another sycophant in a world of bullshit.

phil yates said:

I read a test report recently (can't remember where) by some know it all dick who was loaned a MkIII for testing. I had a feeling it was a recent test but not sure, I have read a lot of stuff on MkIII's having never before owned or ridden one so lost track.

He criticised everything, more about Commandos than MkIII's in particular. But he commented that the one redeeming feature of the Commando, the AMC gearbox had been ruined by swapping the gear change lever to the left. Made it feel like a mush bowl he claimed.

What bullshit! My gearbox feels as nice as any Norton gearbox I have used and if anything, the long gear change movement may be even shorter. On a good day, neutral is as easy to find as wombats on Joadja road. Also, a little green light goes bing "you are here sir".

So I don't know what the whacker is talking about. I don't know if ratios were changed at all for the MkIII, I haven't yet researched it. First to second could perhaps be a little closer but more going down than up. Torque covers up. Second is sometimes just a bit tall in a rolling turn at an intersection, with first being fractionally too low. But that was always a Commando trait in my opinion.

I would never want a five speed box, not for street use. It is something of a modern luxury to be on a bike with so few gears as opposed to thrashing backwards and forwards with six gears, as per modern trend, never knowing what one you are in or should be. My Beemer told me on the dash, and you needed it!

The tester was a claimed authority of some sort. Just another sycophant in a world of bullshit.

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Just thinking, maybe no one told the guy it was one down, three up on the MkIII.
Took off in fourth.
And wondered why top speed was 30mph when he got to the bottom of the box.
And why is neutral between third and fourth??!!

:?:



:lol:

Time Warp said:

:?:

:lol:

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Very accurate Time
It matters not what anyone thinks. That's why Hobot has an important place in here. He offers a point of view not supported by many.

I'm not weird, just sick.
But I'll get better, promise. I've been giving a lot of thought to this gearbox issue and I can't conclude anything but that the tester is/was an ill informed idiot. There is nothing wrong with the MkIII gearbox that I can pick.

On a totally different note, today I noticed the side stand getting harder and harder to flick out with the heal of my shoe, to the point where I couldn't. I thought my foot was shrinking, but upon inspection found the bolt had loosened and the stand was tucking in under the frame on retraction. I will get Jenny to re-tighten it when she is down there counting teeth on my C/S sprocket. She is pretty excited about wearing my grey dust coat. But again I told her, if you don't put on some underwear, you are not going down there. The neighbour will have a seizure!!

Sorry Les, where do we put this post??

Jenny fixes gearboxes and counts teeth on C/S sprockets.
Also very handy on CSU propellers.
Superb flyer as well. I taught her.
But never rides the Norton because her feet can't touch the ground.

Sorry Les
Totally off topic. But all Norton mechanics should at least learn to fly an aeroplane before laying a spanner on your Norton. Riders? Not so much. Riding a Norton is a lot more fun than flying an aeroplane, any aeroplane!!

just above ' Test Conditions ' left column , spec sheet . " Milage at completion of test . 1170 .

Note : AT COMPLETION . ! well run in indeed . :roll:

The Two Wheels ( mag. ) Test of the Red Interstate , where they whined versifferously at its gutlessness , had I believe almost 1.000 miles on it at the ' completion of test ' .
Most people have some idea how warm it sometimes is here . So after sitting idling in traffic , a dozen timed runs down the dragstrip , and neumerous ' hot laps ' around
Eastern Creek , the TEST and ' Run In ' for the supplyer , Was Completed . Or was that Running Out .

As 2.000 careful miles run in , and a further 2.000 of restrained use is at least preferable for Full Capeability Potential , we can see a few twerps were a few screws lose themselves indeed .

Matt
I worked out long ago that road tests aren't really worth much. A bit of a guide maybe if you know nothing. The Combat was tested as being the hottest and best Commando ever. On the strength of that I bought one (well, I fib, I was getting the sucker regardless of what they said). Hottest? yes. Best? yes, until 3000 miles where upon it was in more pieces than my mechano set. But god it was a beautiful machine to ride. I will never forget it.

English and American tests gave us a better clue. Chris Wright couldn't even turn the motor over. He was waiting for the MkIII but was three years too early. Then he fell off the BSA standing still and they sacked him anyway.

Across the big pond, they were burning out clutches and tyres to achieve best standing quarter times, as if anyone but Hobot was doing or much interested in that.

The poms were better, but could only do tests two weeks a year, due inclement weather. I didn't want to know what a Commando was like with chains on the tyres riding in ice and snow.

So if you don't make your own mind up regardless of tests, you are a silly boy.
We were all silly boys for buying Commandos in the first place. And still are.
They are very addictive.

But what about the MkIII gearbox? Les has one, so what does he think re the gearbox?
Or is he still counting teeth lying under the chain? It occurred to him he didn't know himself.

:roll: :roll: :roll: Phil , as you know 1974 -77 used 22 tooth sprocket on the g/box the US used a 20 tooth , re the feel of the G/box on MK3 never had an issue except when I had a combat and a MK2 then went for a spin on the MK3 made you think . So I sold the Combat and MK2 no more problems about thinking what gears went up and down Ha!!! The big differences on the later AMC 3 was stronger cases on G/box and 2nd gear got an extra tooth 18 to a 19 hence going from a 1.704 ratio in second to a 1.614 in the 74-77 models . Why they went from right to left was US laws , funny they never shifted the gear stick in their cars to the left .We change manual gears in our cars with the left hand and they change theirs with the right . But on bikes they like left foot changes aint that America for ya but their house light switches work in reverse too , might upset some yanks here . Any way never had shift problems on MK3 "s and yes the neutral light is handy . Not all bike .reports are the same as with two different riders that is what makes us humans special .

Norton Dave said:

:roll: :roll: :roll: Phil , as you know 1974 -77 used 22 tooth sprocket on the g/box the US used a 20 tooth , re the feel of the G/box on MK3 never had an issue except when I had a combat and a MK2 then went for a spin on the MK3 made you think . So I sold the Combat and MK2 no more problems about thinking what gears went up and down Ha!!! The big differences on the later AMC 3 was stronger cases on G/box and 2nd gear got an extra tooth 18 to a 19 hence going from a 1.704 ratio in second to a 1.614 in the 74-77 models . Why they went from right to left was US laws , funny they never shifted the gear stick in their cars to the left .We change manual gears in our cars with the left hand and they change theirs with the right . But on bikes they like left foot changes aint that America for ya but their house light switches work in reverse too , might upset some yanks here . Any way never had shift problems on MK3 "s and yes the neutral light is handy . Not all bike .reports are the same as with two different riders that is what makes us humans special .

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Dave
Thank you for this. I was wondering what changes may/may not have been made to ratios for the MkIII, interesting.
I have never ever had to "think" when swapping from right to left gear change, nor up or down. Or inside out. It just
never has bothered me. As kids we owned a horrid old Oz bike called a Waratah. It had a right gear stick change and ours
was always falling out due a stripped thread. That made you think. Like where the F…. has third gear gone?? Where
the F…. has the gear lever gone? We would spend the rest of the afternoon looking for it up and down the old bush
track we rode the bitch of a thing on.

I've never read it, but always assumed the US law regarding uniform gear change for all bikes was for common
control position with Japanese bikes which were by far the majority. And also it made sense to have front brake
and rear brake on same side as each other. Clutch control and gear change on the other. Just my assumption,
nothing to do with a preference for one side or the other. As I said, it never bothered me where any of them
were. Still doesn't. I once got smart as a kid (age 9) and tried driving mum's VW into the garage with my legs
crossed. Worked fine until I went to stop and pushed my left foot down hard thinking clutch. But it was
accelerator. More upsetting than hobot hitting his tree at 300mph. Even more when dad got home and saw
the crumpled front bumper bar. I told him my foot had slipped, too scared to tell the truth.

Yes, all testers are different in their opinions, on some things. But referring to the same gearbox as feeling
like a mush bowl, or similar comment is a death sentence job in my opinion. The man was eventually rounded
up and summarily executed, in front of his terrified family of Suzukis and others.

We won't be hearing from him again!!

As soon as I saw the word 'Combat' I got all attentive

I don't have a MkIII, but have a MkIIA 850; no crossover, but the same gear ratios, and you're right about the gap between the gears - can be nasty on downshifts with unexpected rear wheel drifting into corners. Apparently it was done to keep the revs down for noise regs testing, but marketed as a 'better matched ratios' thing.
Where it is better is going from 2nd to 3rd, where most of my 'happy times' on the bike seem to be - it's a noticeable step up on my slightly overgeared Combat.

Back to the proper Norton :mrgreen: I read that they got some stick in the USA regarding the claimed standing quarter times, as the US testers couldn't achieve the factory numbers (like Japanese horsepower 'at the crank'), and certainly didn't believe them, so they sent Norman White over to California







I like the off-topic photos - I had a go in a Piper Arrow a few years ago, but at 6'10" there wasn't any room for my legs; 'full, free and correct' rudder movement simply wasn't in it :roll:
My 'day-job' vehicles have funny seats that pop out quite fast if you feel things are going badly and pull the yellow & black handle. The Lightning had a short cockpit and wasn't ideal for big lads as the windscreen frame would have your legs remaining in the cockpit on ejection.

I prefer Commandos

I like the off-topic photos - I had a go in a Piper Arrow a few years ago, but at 6'10" there wasn't any room for my legs; 'full, free and correct' rudder movement simply wasn't in it :roll:
My 'day-job' vehicles have funny seats that pop out quite fast if you feel things are going badly and pull the yellow & black handle. The Lightning had a short cockpit and wasn't ideal for big lads as the windscreen frame would have your legs remaining in the cockpit on ejection.

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I prefer Commandos

That's my 1967 235 B. If I croak it, at least Jenny can get herself back on the ground. That's the idea of teaching her to fly it.
It goes a lot better than an Arrow, but fixed gear undercarriage. Nothing like the Cessna Dragon Fly jet I tried. Hobot would have blown his brains in that.

So noise regs responsible for the gear ratio change?
Hmm, not sure what difference it could make. But I'll believe anything when it comes to idiot government regs. I haven't tried drifting the rear wheel at 5mph. I just don't like having to blip the throttle so hard going back to first. The bike immediately feels like it wants to go up to second again. Not something to cry over, but don't tell pete.v about it, please.

Second to third is indeed nice and fourth is choof around town in a lazy fashion. My combat with 19T C/S sprocket would eat it, but I ain't into screaming acceleration anymore. Just cruising around town looking like Johnny Pretty Boy on his new toy. But don't challenge me at the lights (I'm talking cars), she'll go if I let her.

phil yates said:

Sorry Les, where do we put this post??

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Do you really want me to tell you? :? :roll:

phil yates said:

But all Norton mechanics should at least learn to fly an aeroplane before laying a spanner on your Norton. Riders? Not so much. Riding a Norton is a lot more fun than flying an aeroplane, any aeroplane!!

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Even a Norton powered aeroplane? :shock:
http://en.wikipedia.org/wiki/MidWest_AE_series

phil yates said:

But what about the MkIII gearbox? Les has one, so what does he think re the gearbox?

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It's OK in my opinion but nothing to write home about. The Mk.3 crossover linkage can get a bit sloppy.

phil yates said:

Or is he still counting teeth lying under the chain?

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Of course not, how could I be typing this? :roll:

phil yates said:

It occurred to him he didn't know himself.

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Oh yes I do. 8)

phil yates said:

I was wondering what changes may/may not have been made to ratios for the MkIII,

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Changes to the Mk.3 internal ratios? - None, when compared with the previous "high 2nd. gear" 850 model (1A, 2, 2A) gearbox.

phil yates wrote:
Sorry Les, where do we put this post??


Do you really want me to tell you? :? :roll:

I think I was going to suggest the same when you moved my photos.
But yours, not mine

But I thought better of it!

Thanks Les, I'd be interested to know what approx mileage before linkages get sloppy. And what's involved in the fix.

phil yates said:

I'd be interested to know what approx mileage before linkages get sloppy.

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Difficult to say.

phil yates said:

And what's involved in the fix.

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A new = crossover shaft, shaft bush (the small one in the primary cover), crossover coupling. These can help to reduce play.

phil yates said:

She looks bloody silly with my boxer shorts on under her grey dust coat.

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Probably not as silly as she'd look if she wore them outside her dust coat. :mrgreen:

phil yates said:

So noise regs responsible for the gear ratio change?
Hmm, not sure what difference it could make.

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As I understand it, this was a rolling noise test conducted in second gear, which required the motorcycle to be ridden at a certain speed as it entered the beginning of the noise test area, the motorcycle then had to be accelerated at full throttle up to max revs.

Apparently the higher 2nd. gear ratio lowered the RPM (and thus noise output) over the test distance just enough for the 850 Commando to meet the test requirement.

L.A.B. said:

phil yates said:

I'd be interested to know what approx mileage before linkages get sloppy.

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Difficult to say.

phil yates said:

And what's involved in the fix.

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A new = crossover shaft, shaft bush (the small one in the primary cover), crossover coupling. These can help to reduce play.

phil yates said:

She looks bloody silly with my boxer shorts on under her grey dust coat.

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Probably not as silly as she'd look if she wore them outside her dust coat. :mrgreen:

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Thanks again Les
Mine is still very firm (gearbox, not……..) as it has only 350 miles since rebuild. The previous owner put ten miles on it in five years and took it back to Baxter's who had built it for him. It had gotten dusty, he wanted something else!

phil yates said:

I've ordered in a grey dust coat just for her. It comes with fish net stockings and school shoes, worn with a tie.

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'They' are gonna want to see photos again! :roll:

Will they still be wanting photos??

L.A.B. said:

phil yates said:

So noise regs responsible for the gear ratio change?
Hmm, not sure what difference it could make.

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As I understand it, this was a rolling noise test conducted in second gear, which required the motorcycle to be ridden at a certain speed as it entered the beginning of the noise test area, the motorcycle then had to be accelerated at full throttle up to max revs.

Apparently the higher 2nd. gear ratio lowered the RPM (and thus noise output) over the test distance just enough for the 850 Commando to meet the test requirement.

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How effing ridiculous!!
Typical of mad over regulation.

So it passes the test, complete with bean can mufflers.
Then everybody rips them off and puts on pea shooters.
Then ride around in first, third and fourth only, just
to piss the cops off!!

It is a sad world run by total f…..g idiots!

And I and others have a too bigger gap between first and second. Like a hole in your front teeth.