Suzuki 2 Strokes

I need to replace the power valves on my 91 rm 125 and since i have had absolutely no luck finding a used set i was wondering if any other year besides 89 and 90 could fit with little to no modification?

First of all, welcome to the forum. Sorry nobody has responded yet but I suspect it's because your bike is too new for most of us here. Most of the discussions on this forum revolve around T & GT series bikes of the 60's & 70's.

A helpful tool for you might be an online parts store like Alphasports.com. They list all the part numbers for bikes so you can compare them from year to year. If you're looking for the exhaust valve itself then 1991 & 1992 125's shared the same part number. If you click on the part it will tell you if it's still available through Suzuki, although the price for the valves might shock you.

When I rebuilt my 1985 YZ250 I had to replace most of the power valve system. It was Yamaha's first attempt with one and it was just a poor design. I spent quite a bit for new power valve components (as there were few used ones around still in working condition) right before they went NLA around 2005, then I had to have a machine shop repair the arm itself, also not cheap.