Jump to content


Photo

Formula 750/MCN Superbike rules, help needed.


  • Please log in to reply
4 replies to this topic

#1 RaceFanAdam

RaceFanAdam
  • Member

  • 40 posts
  • Joined: September 14

Posted 21 November 2018 - 15:30

Hi, could someone in the know possibly explain the rules around Formula 750.

 

I have the rules and regulations for superbike and TTF1, F2, F3 etc but looking through old books, programmes and acu handbooks I can't find anything for either the FIM F750 championship (1973-1979) or the British MCN Superbike series (1971-1982) which I gather ran to loose F750 rules.

 

I understand the capacity limit was 350cc - 750cc (possibly 1000cc for the MCN series?) but need help understanding if the series was limited to 2-strokes or 4-strokes (or both), Were the limitations regarding cylinders, weight, chassis design etc.

 

Any help would be great as it's one of the final parts of a large project I’d love to have complete. Cheers.



Advertisement

#2 Paul Collins

Paul Collins
  • Member

  • 959 posts
  • Joined: April 09

Posted 21 November 2018 - 22:13

Well I think FIM Formula 750 rules dictated road bike origins, with original engine casings and external cylinder shape,but I think any frame and running gear could be used, and 200 road machines to be built for homologation purposes.

But somehow Yamaha got around this as the TZ750 was never a road bike only a racer, although they did show a prototype road bike at the Tokyo show just before the first TZ700 came out.

I was reading something recently that said Yamaha argued that the rules werent specific in relation to ROAD bikes, so they built 200 TZ750 racers and got away with it!!

MCN Superbikes was 501 to 750cc and as you say pretty much ran to F750 rules which I think were also 501 a 750cc, 2 or 4 stroke, I think maximum 4 cylinders amd 6 gears would also have applied to both series, but if someone had brought out a 6 cylinder 7 speed road bike I assume they would have had to let it in, as long as they made 200.

Edit to add - towards the end of the MCN series I think they relaxed things a little, as Sheene had a couple of bored out RG500's a 653cc and later a 680cc which he rode in selected rounds.

Edited by Paul Collins, 21 November 2018 - 22:49.


#3 Robin127

Robin127
  • Member

  • 460 posts
  • Joined: May 10

Posted 22 November 2018 - 16:29

...But somehow Yamaha got around this as the TZ750 was never a road bike only a racer, although they did show a prototype road bike at the Tokyo show just before the first TZ700 came out.

I was reading something recently that said Yamaha argued that the rules werent specific in relation to ROAD bikes, so they built 200 TZ750 racers and got away with it!!...

 

Remember also that the TZ350 was raced in the F750 class prior to the TZ700. The building of 200 bikes and them being made available to the public was the argument they made and we all know how successful they were with those bikes.  Anybody seen a Foggy Petronas?...



#4 Paul Collins

Paul Collins
  • Member

  • 959 posts
  • Joined: April 09

Posted 22 November 2018 - 23:35

Yes TZ350's were definitely around in the early days Robin, I remember Saarinen winning at Imola and Silverstone, but I'm not sure if the official F750 World Championship had kicked off at that point or if those races were just classed as up to 750cc races, it's all so long ago now and a test of the old memory, but Saarinen died in May 1973 so those victories must have been in 1972, and according to Adams post the championship started in 1973.

I'm pretty sure the 350's were not allowed in the MCN series, as I remember in the early years of the championship one of the unique points mentioned in the editorial for the race in one of the programme was 'and a race with no Yamaha's for a change'

#5 Robin127

Robin127
  • Member

  • 460 posts
  • Joined: May 10

Posted 23 November 2018 - 16:16

Yes, the first round was in 1973 at Imola, where Saarinen won following on from his Daytona victory in the same year. Although the race in the US wasn't a round of the championship I believe it was run under the same rules.