4 valve Norton Manx

A while back we had a supermono class here in Australia which had no rules other than the bikes had to be single cylinder four strokes. It meant the guys with the most money won the most races. They bought dirt bike motors which were over 500cc and made them very fast, and they blew up very quickly. They also used water cooled MX motors in GP frames. The average guy couldn't afford to race competitively, mainly because the motors were either unreliable or too expensive in other ways.. Those bikes stood around unused for years after the class collapsed. It takes a very good 500cc air cooled single to beat a genuine manx or G50, let alone a Molnar or Walmsley bike. I wouldn't even control the fuel - let them run nitro if they think they can afford it.

Ken
'You did say 500 cc air-cooled singles with no other rules. Or were you thinking of only vintage singles with modern updates, or some other sort of restrictions to keep modern bikes out?;
That's what I said - no restrictions to keep modern bikes out. If you think you can beat a Molnar Manx, bring it on. The Molnar Manx is a modern bike anyway - a retro ! Do you think that because the bikes look different they should not race together ? To me it is about the level playing field and the technical difficulties in getting a bike to go fast. Also spectator appeal and the sound of the races. When we had supermono in Australia, it did my heart good to watch it. Pity about the oversize motors which killed it.

I've been following this thread with interest, and would add the current class specifications that I know of in certain European national championships. Naturally there are also regulations on tyre width, suspension, tyre warmers or lack of, etc. etc.

In France, the VMA run a 650cc Vintage class, which is for 351cc to 650cc European bikes, up to end of 1970 for 4 strokes and 1968 for two strokes, with drum brakes. This was increased from 500cc to allow 650 twins. Next year will see Japanese singles such as the Yam XT/SR 500 and the Honda XLS 500 included. This should not only increase the grid numbers by lowering bike costs, but make for interesting racing. How will the Manxs andf G50s do ?

In Spain, the Class C is for 2 strokes up to 350cc and 4 strokes up to 500cc, all single cylinder with drum brakes. This allows the TSS and AJR Bultacos to rule, witness the speed trap figures. But they normally have good numbers on the grid.

In Portugal, the Class C1 is for bikes up to the end of 1975, single cylinder 2 strokes to 350cc, twin and triple 2 strokes to 250cc and all 4 strokes up to 500cc. This class, like the other two classes in Portuguese classic racing, is very poorly supported, which is a pity as they have good circuits at Estoril, Braga and Portimao.

As regards the discussion on replicas, I had a '1962' 500 Manx up until '72 (don't ask!) and now run a 93 bore replica, and I know which is quicker, safer and more reliable. I love it, complete with belt drive, Mikuni carb, Interspan ignition, titanium valves, nicasil bore, Dunnell frame, twin plug head and everything else. But then I had a Norvil disc on the Manx back in the day - must be me. (And I painted the frame white)

A chacun son goût. A safe 2015 to all.

Tom

I think a lot of trouble comes from running races with a mixed grid of two strokes and four strokes. In Australia a while back, the A&B grade races were mainly full of two strokes and I loved watching them. I hate watching mixed races. If two strokes are to race against four strokes, - if I really wanted to win, I'd be on a two stroke however it would mean nothing to me, that is why I don't usually ride one. I think the worst aspect of the mixed grid is something which is pretty trivial - the sound. And you never see decent racing when that happens anyway. We are in the entertainment business. If we don't get decent crowds, 'profit' will always come from rider entry fees. It is a spiral into nothingness. I really love the Lansdown series however it is unrealistic to expect to ever get large grids of those bikes. The rules are a killer of enthusiasm. In Australia we have log books in an attempt to stop cheating. My approach is let everybody do their worst. Unrestricted development. What can you do to an air cooled 500cc four stroke single or a 1000cc air cooled twin which has not been done already ?

Do you think that if you were riding a TZ350 Yamaha or an RS125 Honda and blew a Molnar Manx to the weeds, you would really feel that you'd achieved something ?