R80 motor in an R65 frame?

[steve hawkins]

If it were me and it were a road bike, I would put in a standard R100 motor (post 81).  There is not the performance difference between the R65 and R80 to justify the effort.  Unless you had an R80 engine on the floor of the garage...

You will need a pair of carbs and an exhaust for the new motor, so factor that in.  And a final drive....

Do not worry about lean angles, the engine in my R65 is slightly higher than that on my R100, as although the forks are longer on the R100, they are also longer travel.  With a fat bloke on board (me), there ain't much in it.  And the rear shocks are only shorter as the swing arm is shorter.

You are no more likely to rub your heads on an R65 with an R100 motor in it than you are in an R100.  In fact as the R100 is generally more softely sprung as standard, with its long travel forks, you are more like to rub you heads on a standard R100.

It is the best bike that BMW never made.......

Cheers

Rev. Light

[juliansr]

the r65 or r100 is the best?

[EGRG]

the best way to go fast with an R65 would be to get a faster bike?

This is getting into the category of doing something because it can be done.
Interesting, how development of new engine designs arises from sheer curiosity.

My hat's off to any who try.

Identify the goal
Design,
Have two heads of people you trust look at them,
Modify design.
Will the design meet the goal?
Go.

As it is, many of my ridding buddies down here have cruisers that can only dream of keeping up with the little R65 in the curves.