The search for information and locating original parts has been very frustrating. It seems simple just find a 48, 55 or 60 hp twin cylinder and you have what you need. That is true but to build the best motor you just can’t use any motor. The problem is Yamaha built several different models....3 different cubic inch displacements from 45 to 49, 3 different exhaust systems, and 3 different gearcase ratios.
They did limited production runs of 2 models...the 60D which was raced prior to the 70CES...and the 6f0 which is the 49 cubic inch version.
The strange part is the cylinder sleeve porting is similar on all the motors, as is the crank.
Our T750 rules allow two cylinder up to 49 cubic inch models to race. That allows the 6F0 Yamaha blocks and the Suzuki motors to race.
The Suzuki model is very rare and I have only seen one short shaft with power trim in Ontario.
https://alberton.southafricanlisted.com ... 68463.htmlI started this thread years ago and got some people interested and one person building a Mod version.
Here is where he started posting about his project.
https://www.boatracingfacts.com/forums/ ... maha/page6Now years later here is the finished project
https://www.facebook.com/reel/1140064363912807Now if your wondering why would you want to race this Yamaha against the dominant SST 45 blocks in the class?
Reason...it is impressive!
https://www.boatracingfacts.com/forums/ ... ecord-1986
