March/April 2017:
I'm happy to confirm that it is possible to cross the border from Vietnam to Cambodia at O Yadao ( C ) / Le Thanh ( V ) with a Vietnamese registered bike without any problem.
Simply bought the Cambodian Visa for 35US$, my motorbike was completely no topic on either side of the border and I was in Cambodia after less that 5 Minutes.
Road condition is good on both sides, though the Cambodian side gets some roadworks done right now.
I'm happy to confirm that it is possible to cross the border from Vietnam to Cambodia at O Yadao ( C ) / Le Thanh ( V ) with a Vietnamese registered bike without any problem.
Simply bought the Cambodian Visa for 35US$, my motorbike was completely no topic on either side of the border and I was in Cambodia after less that 5 Minutes.
Road condition is good on both sides, though the Cambodian side gets some roadworks done right now.