There is very limited knowledge on the internet that is in English for modifying specific Japanese scooters from the mid 1980s. So in effort to try and point people in the right direction, we've assembled a list of scooters that are compatible with the traditional styling commonly seen in Japan that are available in North America, Europe, and other markets outside of Japan. Although there are more scooters that are commonly modified within the style we seek, there are only limited models that were exported at the time that can be converted to the Japanese Domestic Market spec.
Most Popular for the Style
North America: 1985-1987 Honda Aero 50 (NB50M) : Tact (AF09)
Likely the most common model found within North America on this list, the Honda Aero 50 (NB50M) can be converted to the JDM Honda Tact (AF09) and JDM Tact Fullmark S (AF09).
1987 Honda Elite 50 (SE50) : DJ-1 (AF12)
The next most commonly found model in North America to convert into JDM spec is the one year only 1987 Honda Elite 50 (SE50). In Japan it was sold as the DJ-1 (AF12). Also sold in Japan with upgraded specs as the DJ-1R (AF12), and the DJ-1RR (AF19).
1986-1987 Yamaha Riva Jog (CE50) : Pelican Jog (27v)
The third most common scooter to find in this group is the two year only 1986-1987 Yamaha Riva Jog (CE50). In Japan this was sold as the Pelican Jog (27v).
1992-2002 Honda Dio (SK50) : Super Dio (AF27)
In addition to the 1980s styling that we encourage, a 1990s style scooter that is very popular to modify in Japan was also sold in Canadian markets as the 1992-2002 Honda Dio (SK50). In Japan it was sold as the Honda Super Dio (AF27).
For more information on the difference in generations of Dios, we would recommend visiting this page: https://xn--bnq35iwd30u.com/entry27.html
Not Very Popular for the Style
Now that we have covered the most popular scooters to use for kyuu-gentsuki style, here is a list of some other scooters that could be used, but arent as common.
1987-2001 Yamaha Razz (SH50) : Yamaha Mint (1YU)
The Yamaha Razz, and it's counterpart in Japan, the Mint is not an ideal candidate for modifying as there is very few aero for them, along with them being chain driven (instead of belt) for a top speed of 30 mph. It can work if you are looking to be different or interested in doing a motor swap.
1987-1991 Yamaha Jog (CG50) : Yamaha Jog (2JA / 3CP)
This version of the Yamaha Jog, along with other Yamaha Jogs, are hard to find in America via used websites. If you come across one, you would be able to find some aero for this model.
1992-2001 Yamaha Jog (CY50) : Yamaha Jog (3KJ / 3RY)
This version of the Yamaha Jog was made for a longer period of time, so you might have better luck finding one to buy. This falls more into 90s styling like the Honda Dio. There is a few aftermarket aero available for it.
1983-1984 Honda Aero 50 (NB50) : Honda Tact Fullmark (AB09)
Like the later Honda Aero, we received the Fullmark (think of it as a bigger plastics version) of the Tact. There isnt any aftermarket aero available for this one, but visually it has an older vintage look that could be a good base to start with. Maybe convert out to the regular (smaller) Tact plastics for a different look.
Wrong for the Style / No Aftermarket Aero
While we might not recommend these scooters, it is purely due to the ascetics of achieving proper kyuu-gentsuki style. They were not popular for modifying in that way, as there was plenty of other "cooler" base models to work with.
1988-2001 Honda Elite S / SR / LX (SA50) : Honda Tact Fullmark (AF16)
While this model is VERY popular to modify in America, it is primarily due to the fact we didnt receive the Honda Dio and it was close enough for people to use. This model is the 4th generation Tact in Japan. I have heard this referred to as a "college student" type of scooter in the early 90s Japan. Something just for commuting. There is also another model that is similar to this in Japan that is the 5th generation version of the Tact (AF24). The AF24 had an electric center stand that would "park" the bike when shut off. The AF24 has aftermarket aero available, but isnt confirmed yet as to if it would fit the AF16.

1988-1990 Honda Elite E /ES : Honda Pal (AF17)
The Elite E/ES is basically a stripped down Elite from above. It lacks storage and speed. Think of it as the Spree to the Aero 50. This Elite lacks a variated motor so it has a top speed of 30mph. It also lacks aero. It would be a good candidate for a motor swap, but there is other models that are better bases.
1984-1987 Honda Spree : Honda Eve Fullmark (AF06)
Although the Spree is a very popular and common scooter in America, it is not a good candidate for the kyuu-gentsuki style. There is no aero parts offered for the spree or eve, so custom work would be required, and is possible by modifying a AF09 Tact undercowl. The better looking Japanese body panels from an Eve Smile can be very expensive ($300-$1000) because of their popularity and scarcity. Also, the weak and non-variated motor (similar to the Elite E) has a top speed of only 30mph, requiring a motor swap to keep up with others. We would recommend other models to start and modify with to achieve the correct look rather than using the Spree.