Howdy,
My neighbor recently gave me a 1990 polaris trail boss 250 4x4, with the carb in pieces. He had tried to clean it using a basket in his blender, but the basket failed and the blender ate most of the little parts. Needless to say, I now need a whole new carburetor. So here is my dilema, I live in a remote part of Montana, so online is pretty much my only option. I have found a carb on ebay, but they want about $150 (for a used carb). I also found on Amazon a Mikuni VM30-83 and a VM28-49 that were both around $80 each. So here is my question, the original carb was a VM30ss, I think, which has a 30 mm bore. The VM30-83 has a 30 mm bore but the outlet spigots are bigger. The VM28-49 is almost the same dimensions as the original, but only has a 28 mm bore. Which one should/could I use? Then should I plan on changing the jets to factory specs? (145 & 40) I am looking for the best, least expensive option here.

By the way, the air box is cracked up, so I will be going with a clamp on filter and a new rubber flange to match the new carb.

I haven't really found any good info on retrofitting a new Mikuni carb so any expert advice is welcome! Thanks.

 

Get the VM30 if it's the same price as the 28,then try stock jetting. If you run a clamp on filter you may have to bump the main up. GENUINE MIKUNI HEX MAIN JETS 4/042