I am trying to remember if the FST and FSX ever had a twin top tube like a Master, or was it just a platform like a sport.

I came across a bike that definitely looks like an '87 Master but then I thought maybe it's an FST or FSX.

What was the difference anyway? Maybe the FST and FSX were all hi-tensile steel, versus the Master and Sport being 4130 chromoly ?

From what I remember, the FST and FSX were more of an "entry level bike." The FST came with 48s, and the FSXs came with either Tuffs or OEs -- I can't remember, which, exactly -- probably OEs. I'm sure others will chime in.

Other than the wheels, I'm pretty sure the FSTs and FSXs were the exact same bike -- and yes, they were tri-moly. They had a top tube like a Sport, but if I remember correctly, they were slightly shorter than the Sports. They never had twin top tubes like the Master.

Also, in 87 or 88, the back ends of the Sports and Masters were chrome (or at least had that option). The back ends of the FSTs and FSXs were never chrome, they were painted. The FSTs and FSXs also came with black painted, not chrome, forks. The Sports and Masters -- at least for a time -- came with chrome forks.

And finally, I believe there was a difference in the rear frame platforms after 86. The Sport and the Master had the more subtle platforms in 87 and 88 with the giant pointy teeth, whereas I think the FSTs and FSXs retained the old pre-87 platforms. Of all the details, I'm least clear on the rear platforms. I know there was a difference, but I'm a little foggy.

As stated, no top tubes. late 80's FST's had rear platforms. But the earlier ones did not. FST was bottom of the barrel for a Haro until the design/graphic change. As said, Sports & Masters went tri-moly, FST's got platforms & FSX took over as the entry level. Then the grind / bracket guarded frames started showing up..........

My first real bike, bought new in 1987