Originally Posted by sp115
Genuninly curious as to how the RG500, a rotary valve, square four, is related to these bikes?
The MZ RE 125 was a twin reverse cylinder rotary valve water cooled bike with a highly tuned expansion chamber and very efficient scavenging
this is an early one:
Up until 1962 Suzuki were abymsmal failures on the GP circuits.
In '61 Suzuki built clones of the MZs using the info smuggled out of East Germany by Degner (he brought not just inside knowledge but expansion chamber blueprints, hardware including pistons and a rotary valve and details of the loop scavenging port system MZ had perfected). They created bikes like the RT61 and RT62.
The engine was a mirror image of the MZ with the intake on the left rather than the right but otherwise very similar (and way different to their earlier bikes).
With the new bikes, Suzuki suddenly went from being the joke of the GP circus (I don't think they had a single point from several years of competing in several classes) to regular winners in the following years (I think they got the manufacturers title the first year with the MZ clones in the 50cc class)
The next development was adding more cylinders (something Honda started pushing). They took the smaller engines and arranged them into a square four with water cooling in 1964 to make bikes like the RS64. Same rotary valve, porting and expansion chamber technology that came from MZ.
This is the 1967 version of the RS series:
The RG500 was the culmination of this development. Suzuki took the MZ technology and pushed it very hard over the next 15 years but it was still based on the stuff MZ had pioneered. The RZ is in a sense 4 MZ 125 engines wrapped in a water jacket
(NB I am not an expert - others may have better knowledge - most of mine comes from reading the book about Ernst Degner and Walter Kaaden I mentioned earlier (thanks to M.G.Vig) 'Stealing Speed')