Katana Owners Club U.K.

interesting 400. gsx400 engine, the aircooled 1980's version (with iirc the plasticine crank, theres a reason you dont see these any more) in what appears to be an identical chassis to a gs550kat. its not badged or marketed as a kat, but its clearly infused with the katana family genes. interesting little bike, and quite a rarity to see one thats survived to now..

https://www.ebay.co.uk/itm/GSX-400/3234 ... 0009.m1982

This model was sold as a katana in Germany etc ... The plasticine crank was quickly sorted by a recall and fitting a larger sump. A spot of weld was added to the engine number to show The work completed.
( then people filed off the lump of weld because it looked odd!)
Any still running should be fine.
Never seen one with a Kat seat and panels fitted before though.

notice how, shorn of the word 'katana' the price is incredibly reasonable for what it is.