What year is this?

Advertised as a 81'420, what year was the first plastic tank? Maybe they put a later tank & seat on an 81'

Well that frame is 83 or 84 and 84s had the first plastic tanks, looks like 81 420 motor though.

It looks odd to me too, forks look like 35mm, some one put a after market tank on there and a seat ?

frame CR 1981/1982
rear shocks ohlins ITC 1983
front forks 1981 35 mm !
motor 1981 !420 auto !
front wheels 1981 !
tank ?

Talked to the owner ( nice guy) says 81' frame and engine, longer swing arm, Acerbis tank

The frame in the rear part has been deeply modified....
Automatic for sure....
A mix of different years, why ?
....

Don't know the current owner got it that way, probably an attempt to trick it out like I used to do

agree about the frame, you can tell its 83 or 84 along with the itc shocks and tank...seat and side panel are aftermarket..
silencer looks like an old answer unit with a big gun sticker on it. they never made any swede husky parts.
someone added the older 35mm forks and smaller triples to it. definitely a hodge podge of parts, not someone trying to build the ideal "purpose" bike. if set up right probably still handles well.

thats the factory 84 acerbis tank..they made the husky tanks up into the 90s..the curved area above and behind the pegs gives away the 83-84 frame style.

original picture husqvarna
420 auto WR 1981

Frame does not look modified to me, it looks like an 82 AMX with 83-84 ITC shocks and aftermarket sest and tank.