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What does a Yamaha TA125 race bike have to do with the weather?

What does a Yamaha TA125 race bike have to do with the weather?

Unicla director Mark Mitchell explains his relationship with racing two stroke motorcycles in the 1970s and testing HVAC systems in various psychometric conditions.

 

In this video Mark explains as a teenager he raced Yamaha two stroke motorcycles in the 1970s.

A Yamaha TA125 was his pride and joy, and the bike on which he had the most success. Mark explains how he mastered most aspects of racing this bike except for the tuning of the carburettors which is a task very dependant on understanding atmospheric conditions and features from the psychometric chart.

Basically, the weather.

Maximum engine performance and horsepower from a carburetted engine can only be achieved by getting the air to fuel mixture just right. This mixture is influenced by the dry bulb and wet bulb temperatures of the air entering the carburettor, as well as absolute and relative air humidity.

Mark retired from racing at the grand old age of 21 without understanding these parameters and therefore didn’t properly master the tuning of these exciting machines on his own.

Fast forward 40 years, and after a career as a student of mechanical air conditioning and refrigeration, and now owning an advanced vehicle thermal test centre, Mark has re-visited this challenge by acquiring two TA125 machines. The bikes have been restored back to their original condition, and the plan is to run the bikes at full power in the main Unicla vehicle test chamber.

Modern technology will be used to manipulate the weather conditions in the chamber to suit specific racetracks where Mark competed. The carburettor settings will be tuned accordingly.

It will be a journey back in time, a reflection on something learnt, a celebration of modern technology, and a lot of fun.