Motorcycle Questions? Ask a Mechanic.
Hello, the motor from a 77-79 860 GTE or GT (non electric start) will both work and are 863CC as the 900 GTS engines were.
Sourcing one is in a word, difficult. There are currently some case halves on ebay and other needed parts to assemble an entire engine. You might also want to try Oddball auto parts They have helped me source hard to find vintage bike parts in the past.
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