The KLT 200 also had locking differential. I used to own one. Go to the back of the trike, and look at the very rear of the "swingarm" or hub, where the axle goes through. There should be a square shaped plastic cover. Pop that off, and roll the machine ahead until you see a mechanism. There is a plate on top of it, and underneath there is an allen bolt. You loosen the allen bolt to have it in "differential mode" and tighten it to have it in "locked solid axle" mode. As far as the lube goes, on the KLT 200 I had, there was only a grease zerk, I believe right by that allen bolt. In differential mode, it can turn on a dime on pavement, but sucks everywhere else IMO. Never have it in differential mode if your going up a hill. The machine will have a tendancy to do a turn as you are going up the hill, or have no traction, as in one wheel drive.
THE 80's RAGE! Currently owns:
81, 85 Yamaha Tri Moto 125
83 Yamaha Tri Moto 200 x2
82,83 Yamaha Tri Moto 175 project
85 Yamaha Tri Z 250
84 Kawasaki Tecate 250
84 Honda ATC 70
85 Honda ATC 350X
84 Honda ATC 250R
(2) 84 Honda ATC 200x
82, 83 Honda ATC 185s
81 ATC 200
Lots of other parts and bikes