Despites the restriction on engine capacity, vietnam is fabulous for riding.
Get the Vietnam Road atlas (blue with white bridge) from the bookshops near the post office in Hanoi and start playing.
We did Hanoi - Mai Chau - Son La - skipped Dien Bien Phu in favour of an incredibly beautiful shortcut from Tuan Giao to lai Chau - Pa So (where we spent some extra time in the hills) - Sa Pa
Sa pa - Bac Ha (best on sundays) - Ha Giang - Meo Vac - Bao Lac - Cao Bang
There are not many tourists outside of SaPa and Bac Ha at all, but this northeastern loop is drop dead beautiful. You're supposed to have a permit if you want to stay overnight in the border area though. We didn't want the hassle and rode the whole bit in one day, which is a bummer as it's too beautiful for one day. Two up with gear, a Minsk is powerful enough for this stretch, but only just. No alternative though.
If you've more time, the ho Chi Minh Highway South of Pho Chau is gorgeous.
No need to carry fuel, but some rain clothing and gloves are needed, you may have some rain. Road conditions are generally great.
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