The smaller the cylinder volume, the more sensitive it is. If it is a 4-stroke, valves needs to be cleaned more often for example. So I vote for th bigger bore.
50cc , 65cc , 85cc , 125cc , 150cc , 250cc , 500cc are the most popular but there are a few others
Honda Unicorn
the ca95 is the 150cc sometimes referred to as the baby dream .was built in the 1960s
1.2L
The Honda Elite Deluxe runs with a 150cc engine. What a beaut! They run forever!
65cc: ktm and kawasaki are best 85cc: Honda, ktm and Yamaha are best 125cc: Yamaha and suzuki are best 250cc: Kawasaki, Yamaha and Honda are best 450cc: Honda, kawasaki and Yamaha.
Get one star rank or better on all 150cc cups.
Base price for a 2008 RM 85cc was $3099.
150cc is 0.63 cups.
Honda is way better
you need to get a star rating or better on all 150cc cups
125cc 85cc