Forum

[Ian W]

Hi chaps, just wondering if anyone could help me with some info.

I'm interested in what the horse power of twins were / are, 500cc, 700cc and 750cc engines. Ballpark figures, no real reason just interested.

Thanks
Ian W

[Chris Tindal]

According to Roy Bacons book the BHP of the twins is:

500 Twin 25-26
Meteor Minor 30-33
Meteor 700 36-39
Super Meteor 40
Constellation 40-51
Interceptor 52.5
Rickman Interceptor 56

[Ian W]

Perfecto, thanks Chris, that was very nice of you to look that up for me, cheers.

[Mark M]

Ian, as Chris says but one detail is doubtful. The quoted figure given in the sales material at the time gave 56 bhp for the Rickman Inter but the engines are the same as in the Enfield Interceptors quoted as 52 bhp. Salesmanship? Probably! REgards, Mark

[Riggers]

Hey Mark. I think that when the Rickman came on the scene it was just at the time when manufacturers started getting a bit 'over enthusiastic' with their BHP claims. I reckon this was caused mainly by the Japs who used to claim ridiculous output figures for thier little tiddlers. Just one example was the Honda CB250 with its claimed 30bhp and 100mph performance. At the time I was duped and bought one. I reckoned it fealt more like a genuine 20bhp which managed a genuine 75 to 80mph as long as the wind was with you. I flogged it soon after buying it and brought home a Triumph Trophy 650 which claimed a more convincing 41bhp and propelled you at what seemed to be a more genuine 110 to 115mph. Cheers. Tony.

[Mark M]

Riggers, that's my memory of that era too. The 56 bhp claim seems to have popped up in American sales literature so you can make of that what you will! And my Honda 250 K1 which needed a thorough rebuild before it became my first bike would definitely exceed 100mph. In first. Honest! REgards, Mark

[Anders F. R.]

Mark M: If the 56 bhp figure first appeared in US sales literature, it might be bhp SAE. The Americans had (maybe still have?) a habit of giving bhp measured after a different standard than us, that normally give bhp DIN. The SAE figures are always higher than the DIN figures, due to the different measuring method. Maybe that's the reason? Regards, Anders F. R.

[Mark M]

Anders you could be right (I'm not an Engineer!) but these figures were quoted in the early 1970s before the UK was a member of the EU and the DIN specification was a European one so I suspect we would have used the same Imperial measure as the US? REgards, Mark

[STU]

The Rickman ran different exhausts and silencers from the Enfield bikes - would that have made any difference to the output, I wonder?