1983 is a different tooth count but 1984 and 85 are compatible , in 1985 the gears were made a little thicker but fit just the same , I guess Honda realized their was an issue . Also a few years of the xr200 were also compatible , 1990-2002 I believe .
Here is a set , little pricey but an upgrade if yours is an 84 model .
https://www.ebay.com/itm/20431707674...Bk9SR_SWmr34YQ