The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Crossrodes on October 02, 2009, 01:09:47 PM

Title: HP Rating
Post by: Crossrodes on October 02, 2009, 01:09:47 PM

I believe I have read two differing statements regarding the rating of the R65.  One said that the R65's built for the European market have a lower rating than the ones built for the US market.  The other statement said the opposite.  God knows what was built for the Canadian market.

I have a '79 R65 which was built for and originally sold in the German market.  The bike was later imported by the original owner when he emigrated to Canada.

So does anyone know the truth about these HP ratings???

And the answer begs another question...what is/are the difference(s) in the engine design that would deliver more HP?

Title: Re: HP Rating
Post by: Bob_Roller on October 02, 2009, 02:03:34 PM

There were two different hp ratings for European markets, I don't know the precise numbers .

The reason, was for driver licensing, I think it was mandatory to have a low power bike, until you gained some experience, I'm sure our, European members can fill in the details .

I know insurance played into this as well .

The low output engines had 26 mm carburetors .

Title: Re: HP Rating
Post by: Barry on October 02, 2009, 02:59:07 PM

In Europe at least the original 79 - 80  R65 was 45HP and this was increased to 50Hp for 1981 models by increasing valve sizes.  Inlet from 38 to 40mm and exhaust from 34 to 36mm

The R65 with 26mm carbs was a 27HP insurance special. I would think these are extremely rare.

That would make your R65 a 45HP model if it has the standard 32mm carbs.

Title: Re: HP Rating
Post by: Motu on October 02, 2009, 10:39:56 PM

R65 mono has 48hp and max torque at 3,500rpm.