Nice bike, I’ve had three they are very comfortable (relaxed 69 headtube angle like early Ritcheys and Stumpjumpers), about 30 ponds and full of touring bosses. Your bike is a 1986…they started making frames for that model during mid-85 to sell as an 86 model as best I have been able to gather the little information available. There should be a 5 in one of the three first serial code characters. Something like [X5] but sometimes pre-ceded by an F perhaps for a Japanese Factory. At one time during the 87 model its production changed to Taiwan.
-The Nitto MT-2 stem is reversible, still can be purchased for around $75-100. The bar should also be a Nitto B801, one of the nicest mountain riser bars, in my opinion.
-Tange Mountain Frame with earlier models came with Infinity Tubing (see Frantiks’), top tube has a nice “ping” to it, almost Tange Prestige-like. Sizes over 20” came with two bottle bosses on the downtube.
-The beautiful Suzue hubs have cartridge sealed bearings which were on the early side for production mountain bikes.
-The fork is made by Tange, this is only 2[SUP]nd[/SUP] year of uni-crowns, third if you include late 83 adaptation in some Ritchey-Fisher bikes. This was probably based on the Specialized “lost wax” (if someone can explain that term to me I will appreciated) uni-crown with the lugs. Coming from the crowned forks, the lugs probably were believed to be necessary on MTBs at the time (just guessing here).
Nutted Axles in 86 changed to QR’s in 87, also the roller-cam changed to U-brake.