Barton Motors / Norton motorcycles etc

911uk MODERATOR EDIT: Moved from a different thread.

Funny you should mention Norton's - because I am writing a book about my motorcycle exploits for which the first issue was to find a way to make the gearbox of a fellow students 600CC dominator more suitable for racing (as the lower gears were too low to use on track and we couldn't afford a full C/R gearbox changing all 8 gears). We found a way to make the 4 gears closer ratios by making and changing just the sleeve gear ratios - just 2 gears to manufacture (because of the sleeve gear system and top always being 1/1). We made a sleeve gear with a ratio to speed up the layshaft so all the internal gears (1st, 2nd and 3rd) would then be higher - and third was then closer to 4th because 4th was always locked out at 1/1. 3rd to 4th became the same as a Manx ratio and it was this invention that enabled me to start Barton Motors and initially manufacture and sell those gearbox conversions World-Wide - leading on to the Sparton's (that were fastest at the TT and 1st and 2nd at the North West 200), the Phoenix fours (that won several TT's, The Silver Dream racer (for the film), several upgrades for Barry Sheene's Suzuki (including a 6 speed gearbox to replace the TR500 5 speed box and making his RG500 into a 650 (later adopted by the factory), the carbon fibre framed Armstrong 350 engine (that won the British Championship for several years and obtained podiums in full GP's etc.


Sorry - a bit off subject but while on Norton's and compression ratios - we fitted huge inlets and carbs and very high compression pistons to it - but then it only ran well if it was much too rich (because we could not influence a change in ignition timing throughout the range in those days and running too rich slowed the burn speed with H/C and made it faster and with more torque).


You are right about the studs - the reason they broke was because the only place not sealed off from the outside atmosphere was where the head joined the cylinder so moisture could creep in and slightly corrode the stud just there.


Then corrosion created a notch so "notch metal fatigue" set-in and because the cross sectional area gragually reduced just there so the load/unit area increased and each time the engine was run, got hot and then got cool again the thermal expansion of the cylinder and head stretched the stud increasing the tension in it creating fatigue cycles.


Eventually the cross sectional area could not withstand the cylinder head torque that had incr3eased of course as the cylinders and heads expanded and when they broke you could clearly see the typical metal fatigue polished rings where the section had gradually cracked and the smaller area where it finnaly broke- text book stuff.


Plastic coating largely overcame the problem but also keeping cars in heated garages for most of their later life also helped.


Baz

Again starting with an apology for drifting off topic, and bow to the mods decisions should they bin my ramble ...

Not binned but a new thread started by 911uk moderator.


ALL very interesting Baz, cash and engineering education were ever very limited in my automotive formative years, Motor Cycle Mechanics mag was the primary educator and apprentice through to tradesman income and other social circumstances, ever demanded non mechanical priorities took precedence over the desire to make machinery go faster.. (-:

Those were different times indeed. Over boring cylinders, higher compression pistons, fitting twin carbs, lumpy cams, all limited to standard gearbox ratio issues on bikes that were at times older than us, and with engines that we "tuned" to have minimal power bands, all long before the days of "easy money," that has long since created a different set of options with the passage of time...

But it was sure interesting to learn that it is all so easy to totally spoil the enjoyment potential of a machine by setting out to "improve" it`s performance, destroying it`s original engineering balance while spending plenty of cash in the process..?

Seems to me that there will ever be plenty of folk who like me were keen to learn to be able to maintain their machines themselves, in order to be able to afford even to own a machine in the first place, or to permit them to stretch that bit further to be able to afford a more expensive/performance machine in time.

Having gained access to basic knowledge and tools, the next stage was seeking to make it go yet faster, entirely natural...? (-: Seeking to control the extra power generated by way of improving handling would have to wait for a time of "disposable income" to arrive...oil soaked rear tyres, drive train shredding engine performance, worn swing arm bushes etc.etc. and all with brakes designed for a less urgent rate of progress....Gaining rudimentary automotive engineering appreciation was a... slow... process indeed in the pre internet world..and was perhaps a tad more..err.. hands on dirty fingernail, many cuts and bruises to body and wallet alike, in order to increase understanding than might be absolutely necessary today..

Lapped the I.O.M. on my old 600 Dommie with wide-line, and years later did the same on the isolastic 850 Commando. Of course the Commando`s engine rubber mounts did not vibrate the teeth out of one`s gums as did the Dommie, and was far more powerful but the frame seemed bendy when flat out on the slow consecutive sweeping bends coming into Ramsay causing me to wonder if it was any kind of improvement over my old featherbed...(-: Returning to m/cycling in later life, my last bike a R850R was a then new design and far superior to all I had known before, but still it had it`s faults...(-:

Backing up a bit in time, When I moved on to four wheels Vizzard`s Tuning for Speed, Cars And Car Conversion mags of the late 60`s took over in terms of acquiring mechanical knowledge... But still limited funds and equally limited brain power, equated to creating similar imbalanced cars by prioritising engine performance over all, it took rather too long to learn that it was best to buy a machine initially designed to provide high performance as opposed to dragging old mundamemobiles out of their initial design configuration to force them to go faster.... But then to be involved in the former definately was key to gaining a level of appreciation as to how stupid one could be...(-:

Seems I am still learning today on this forum... just that remembering it and much else seems ever more difficult... Greatly appreciate your input Baz and that of the rest of the guys here..

Cheers. :thumb: