Gunze Sangyo offer both plastic and multimedia model kits. The plastic kits are like the typical plastic kit. And on the other hand the High-Tech multimedia kits are like no other motorcycle kits I've seen.
NOTE: I am not a retailer and the kits listed here are not for sale. If you're looking for a place to buy models, check out my mail order houses page.
Note: The 1/12 High Tech model kits are are very different from the typical plastic model kit. In addition to the plastic parts, the kit includes die-cast metal engine and frame parts. Wire rod for the wheel spokes and control rods. Photo etched parts for chain rings, chains, name badges, exhaust clamps, and for other fine detail. All this results in a far a more realistic looking motorcycle.
These kit look rather intimidating and rightfully so. A lot of fabrication is needed and you'll be working with materials you may not be familiar with. You need to assemble the wire wheels. Cut and bend wire into complex shapes for control rods. Bend photo etched pieces into complex shapes. Etc.
The only con that I can see is that some parts that are die-cast are out of scale and toy like because of the limitations of moulding in metal. Overall, they are incredible motorcycle models.
Having said that: These kit these are only recommended for experienced modellers.