Yours is an ST400 built in 1987. 19" (maybe 21")frame size. Suntour Alpha3000 6 speed indexed shift system. 27" rims and tires.
These are great bikes. I have 4 in the 27" frame size and 2 in the 25" size.
One of my completely updated ST400's is my ride of choice for a pleasant day in the saddle.
Many smaller riders found the stiff (efficient) frame to be too "harsh" of a ride, more in the race models than the ST series, with their longer wheelbases and more relaxed angles.
The basic frameset is well setup for touring, with adequate eyelets front and rear for rack and fender mounting.
If that is your size, tune it up and ride it! It is a quality American made bike.
Due to its age, it may only fetch $200.00 or so on the market. However, the small frame size may have some demand.
Last edited by Ronno6; 02-25-13 at 07:06 PM.