1981 Japanese model. Based on the braze-ons, most likely a Limited, as previously suggested. During this period Limited were typically Ishiwata 022. If you want to be sure, pull the fork and check for a stamp on the steerer tube then check the size of the post. Ishiwata 022 typically uses a 27.2mm post, 024 uses a 27.0mm and a 26.8mm post is typical of a Tange tube set. Anything smaller than that is into the range of a plain gauge tubeset and a lesser model.