pair of 400's spot 10 things different....

84 WR 400 was not the last of the twin ohlins

and the silencers are different. right is stock...left is aftermarket. left bike missing chain tension roller

the 1985 WR250 and WR400 were the last. The WRX 250 and 400 came out in mid 1985 and that became the end of the beloved twin shocks as there were none in 1986

These were liquid cooled twins ?

That chain tensioner and the up stop chain roller are very important. I've seen the case crack with out them. I believe there was a 400 air cooled twin shocker posted here somewhere.

The WR 400 was, I cannot speak for the 250 as I was under the impression it was a leftover 1984 model like the 400. The 84 250WR is aircooled.

The 84 250wr ac was kit bashed with left over ac parts they had cr cylinders on the WR tranny. My 83 250wr ac and my 84 250wr ac are two different rides. At '84 1/2 the 250wr was liquid cooled.

"and the silencers are different. right is stock...left is aftermarket. left bike missing chain tension roller"

its actually the stock muffler with mods to the end cap. the bike on the left is a Californian bike but I gutted the spark arrestor out, fitted a straight pref core and reversed the cap and added a down turn to quiet it down. if you look you can see the two spring hangers still on it ( I painted it silver !)