The construction looks like the Bill's pipe on my Tri-Z. But there's just no way to know, for me anyway. My Tri-Z pipe has a tag on it that says Bill's so that made it easy to identify! I need to post up pics of my running 250R's pipe. It has an answer silencer, but the pipe I'm not sure of. It's definitely aftermarket and painted black.
1986 Tecate
1984 Tecate
1985 Tri-Z
1986 ATC350X
1985 ATC250R (2)
1985 ATC125M (2)
1982 ATC70 - Original Owner
175 TriMoto Frame with Pro-Tec Rear Suspension
3-Wheelin' since '82