650 SS Head

acotrel said:

Aermacchi 350s have won a lot of classic TTs. They arrived in about 1963 just as the two strokes took over. Notably, a while ago our Bill Horsman won the IOM Classic TT on one. He was told that he should have been there years ago. He was one of those guys that if you saw him on the grid beside you, you knew it was probably time to go home.

Click to expand...

How long after 1963 did all these wonders take place?

Rohan, About metallurgy - plating techniques, casting technology, selection of materials, heat treatments, corrosion resistance and strengths all come down to metallurgy. Italian bikes have shown some of the worst examples of how it should be done. When you say that the Italians didn't use the copper and nickel precoats to their chrome plating, what are you really saying? It is not rocket science , the outcome is entirely predictable. The common definition of quality used in all Free Trade Agreements is 'fit for purpose'. A better definition is 'fit for purpose with obvious attention to detail'. The Italians did not lose the plot, they never had it. This issue is having a major effect on our Australian economy. Our wages are high and to justify our overheads we must compete on the basis of quality and charge higher prices. Our remaining vestiges of manufacturing industry still have the mentality to cut wages and join the race to the bottom. A race we must lose to the Chinese and Indians.

Triton,
'How long after 1963 did all these wonders take place?'

In the last decade or so , however a 350 manx and an aermacchi 350 both have the same opportunity to access modern technology, and both have the same design limitations as far as number of cylinders, valves and gears are concerned. In fact the Aermacchi 350 is a pushrod motor - it will still beat a 350 manx most times. When it raced in the mid 60s, the main opposition became the Yamaha TD1C , and the Suzuki TR250, so both the aermacchi and the manx then became non-events in most races. I would not have liked to race a two stroke on the IOM back in those days, it would have been extremely scary.

acotrel said:

Triton,
'How long after 1963 did all these wonders take place?'

In the last decade or so , however a 350 manx and an aermacchi 350 both have the same opportunity to access modern technology, and both have the same design limitations as far as number of cylinders, valves and gears are concerned. In fact the Aermacchi 350 is a pushrod motor - it will still beat a 350 manx most times. When it raced in the mid 60s, the main opposition became the Yamaha TD1C , and the Suzuki TR250, so both the aermacchi and the manx then became non-events in most races. I would not have liked to race a two stroke on the IOM back in those days, it would have been extremely scary.

Click to expand...

So you were talking about the modern series of classic races.

Irrelevant to your "point" about Norton and Macchi in 1963.

Why is it irrelevant ? I suggest the comparison is fair. Time has passed and both bikes have had the same opportunities for development. The playing field is still the same, the speeds are just slightly higher for both bikes. Neither have had radical design changes such as four valve heads or watercooling or fuel injection fitted. The only difference might be that back in 1963, the aermacchi would have had five speeds as it came from the factory. A lot of manxes were fitted with Schafleitner boxes. The problem was that the Aermacchi came along too late. By the time it arrived the days of the four stroke single cylinder racer were over. However just in an objective comparison, the Aermacchi was a better package.
Those two bikes never get raced in the same historic class in Australia. If you own an Aermacchi, you have to contend with the methanol fuelled two strokes in Period 4, Manxes run in Period 3 Pre '63). It's always the same problem when you base race classes on date of manufacture.

Fine. When new model 350 Aermacchis arrived in 1963 they made the already out of production 500 Manx Nortons look silly, twenty years later, after both factories were long closed.

I hope I've got that right.

A friend has owned three 350 Aermacchis. One was an Othmar Drixle Drixton 350, one an ex Charles Mortimore Ala D' Oro, the other was also the genuine item. Compared with a Manx, they were relatively cheap. However like a lot of things they were a waste of space. When he raced them, it was always against bikes of entirely different technology. They way our historic racing is run, it is difficult to ever get onto a level playing field with many very desirable bikes. I once rode the Drixton 350 and it is a great bike, however if you want to race competitively on an old bike, it is not the way to go in Australia. A very sad situation.

'Fine. When new model 350 Aermacchis arrived in 1963 they made the already out of production 500 Manx Nortons look silly, twenty years later, after both factories were long closed.

I hope I've got that right.'

The 1964 350 Aermacchi made the 1962 350 manx Norton look silly. A 500 manx is faster. What I am saying is that both the 350 manx and the 350 Aermacchi are bikes of similar technology, and the 350 Aermacchi was the better package. By the time they ended up on race grids together in about 1964/5, the exercise was irrelevant. The two strokes had arrived.

Today in New South Wales, there is a group of guys who specialise in bucket racing. A major problem has been in adjusting capacity limits in races which cater for both two strokes and four strokes so that the game is fair and equitable. My feeling is that there should always have been separate races for two strokes and four strokes. It would have save a lot of angst.

You're making more sense.

Classic racing is just another formula. People will do and spend what they have to, to win.

Triton,
'
Classic racing is just another formula. People will do and spend what they have to, to win.'

With me it is not about winning, it is about getting the lovely competitive ride with a bunch of guys all on bikes of similar technology and capacity. That is the best fun you can ever have. I don't care if it is in a two stroke race, a superbike race, or a thunderbike race, as long as it isn't a mixed grid of various technologies. I cannot see anything wrong with racing a 500 Manx, an SR500 Yamaha, and a Seeley G50 off the same grid, in fact I would love it.
Racing a 350 Aermacchi against 350 Manxes and BSAs would be very inspiring, and there is no easy win in that, even with the best Aermacchi, compared with what a 250 two stroke would do in the same race.

Triton, the last few times I raced my Seeley 850 were a fair while ago. I had a few races at Winton where most of the field were irrelevant to me. There were really only two bikes that I had to beat. There was a guy on a Yamaha XS 650 whom I blitzed, and another who had a Harrier framed 750 Triumph with a Rickman head, and he finished just ahead of me. I had a couple of rides at the old farts meeting at Mount Gambier where I won a couple of races which meant nothing, because there was nobody there who actually meant much. I outrode one guy on a Honda Four who kept outbraking me, and finally beat him when he got out of shape under pressure. However for me, that stuff doesn't justify the expense. It is OK - barely. I see bikes that I would love to race against, however they are mostly all in other classes. I think I have to take up lawn bowls.

acotrel said:

Rohan, About metallurgy - plating techniques, casting technology, selection of materials, heat treatments, corrosion resistance and strengths all come down to metallurgy. Italian bikes have shown some of the worst examples of how it should be done. When you say that the Italians didn't use the copper and nickel precoats to their chrome plating, what are you really saying? It is not rocket science , the outcome is entirely predictable. The common definition of quality used in all Free Trade Agreements is 'fit for purpose'. A better definition is 'fit for purpose with obvious attention to detail'. The Italians did not lose the plot, they never had it. This issue is having a major effect on our Australian economy. Our wages are high and to justify our overheads we must compete on the basis of quality and charge higher prices. Our remaining vestiges of manufacturing industry still have the mentality to cut wages and join the race to the bottom. A race we must lose to the Chinese and Indians.

Click to expand...

What a load of (mostly) drivel ?

English bikes didn't use copper or nickel under their chrome either, in many instances, they just used more chrome to make it good.
They had their own plating tanks, mostly ?
If someone the italians used/outsourced somewhere put the nickel on a bit thin at times, this hardly makes it an international incident ?!!
How many Italian factories operated at a profit around the decades of the 1970s... ?

Repeat - Italian bikes (and bicycles) are renowned for their casting quality.
I'd suspect that some Commando bits came from there (?).

Not those porous Commando heads though....

acotrel said:

'But Nortons had no money, and several designs of inline 4's hadn't made it even to the prototype stage.'

A while ago I mentioned the lack of a Marshall Plan for post war Britain, and this was denied. Yesterday I watched a documentary on the Morris minor and the Mini, and the lack of funds for rebuilding their industry was mentioned again. That wartime and post-war relationship between Britain and the US was very strange and I've read a bit questioning Roosevelt's motives and attitudes towards the British Empire. The assertion was made that there was intention for the US to capture the trade areas in which the British had previously dominated. What is really strange, is that in spite of everything some parts of British industry really excelled, and today the F1 teams, the kit car industry are great. Also some of their defence equipment is excellent.

Click to expand...

No one "denied" it.
There simply wasn't one.
The English were on the winning side.
Don't try to re-write history....

It has been commented, frequently even, that it is somewhat ironic that the US made large profits from their "allies" through the Lend-Lease program (giving arms now, on credit = pay later). And the losers got handsomely paid for, well, losing....

Not that this post-WW2 navel-gazing has much to do wif 650SS heads....

To my knowledge all UK chrome plating was over copper and nickel. Up here in 'Straya I used to work for a guy who apart from being a Senior Engineer was also an MGB owner. He used to maintain that the best commercial chrome plating came from England, he was very critical of Australian and especially American chrome plating, saying that it was little better than shiny crap. He was talking about chrome plated bits specified as original equipment, not after market stuff which was a bit of a pot luck situation wherever it came from, I'm thinking Dunstall mufflers here.
cheers
wakeup

I did an electroplating course - which allowed me to chrome some small bits for my bikes.
(the tanks weren't big enough to do wheel rims or petrol tanks).
This involved stripping off the old chrome, of course.
The nickel underneath is much tougher to remove.
Not all parts I stripped had nickel underneath.
Some of these would have been 1950s or earlier.

Chrome back in the 1950s and into the 1960s was different.
It was applied in a MUCH thicker coat, and then ground and polished back smooth.
Since then, chrome plating has come a long way - it somewhere gained some 'self-levelling' abilities, saves all that that grinding and repolishing.
Really thick ground chrome is reasonably waterproof, and will survive well.

A friend had the front bumper of a Stutz replated.
Now that was an adventure.
The quantity of chrome involved was colossal - as was the final account !
That taught the plater a thing or 2 about good chrome...

This is a pic of a gearlever, circa mid 1950s.
Not sure if it is obvious, but where the chrome is gone is just bare steel.
No copper underneath, no nickel.
Chrome will stick to polished steel perfectly well, bit of a false economy long term though...
The area under the diagonal is just bare steel, to the upper left and right is still chrome.
Will try for a better pic, later...



A lot of chromed rims are just chrome on bare steel.
No copper or nickel is visible when the rust sets in, as you would otherwise expect to see. ?

And this is a chromed tank, as Nortons used to do them.
Circa 1950 ish Dommie, a Model 7.

Thickly applied, and then ground back smooth and polished.
Lookat that chrome - inches deep, and still as good as the day it was applied...



Dunno what this has to do with 650SS heads though, or how we got here....