Brolga Bill's Bike Trail (BBBT)
'Twas Brolga Bill, from Rutherglen, that caught the cycling craze,
He turned away the good old wings that served him many days...
This geoart shows Brolga Bill's bike.
It is designed so you can be like Brolga Bill, and complete the trail by bike.
(and hopefully not come to the sticky end like his mate Mulga Bill)
All the puzzles are about bike riding, and can be solved with an easy online search.
The puzzle
In the 1980s, the first triple chainring bicycles started being sold in Melbourne. Ron Shephard, an engineer and founding member of the MBTC and Bicycle Institute of Victoria relentlessly promoted use of triple cranks to promote cycle touring among a wider audience.
Question: What was the slang name for the triple chainring system? (two words, no spaces)
You can validate your puzzle solution with certitude.