Looks like an excellent bike for the money.
54cm Miyata Track Bike/Fixed Gear w/ Dura Ace 7600 group – $700 (Fishtown)
For sale is an excellent condition Miyata track bike built up predominantly with Dura Ace 7600 parts. It is in excellent condition with low mileage. It has Dura Ace 7600 hubs, DA seatpost, DA 7600 48t crankset (170mm length), DA 18t cog, Koga saddle, Shimano 105 brake caliper and lever, and Cinelli stem (120mm) and handlebars (40cm wide) The hubs spin smoothly and are laced with 28 spokes to Mavic Open Pro clincher rims with Vittoria Rubino Pro tires with plenty of life left. Top tube dimension is 54cm center to center, seattube length is 52.5cm, and headtube length is 145mm. The standover ht is approximately 32″ or 81 cm.
This frame was an extremely high-end frame for its time, and has very little use. It is a splined triple-butted frame, which is a proprietary product that Miyata was making at the time.