1987 Ski-Doo formula plus snowmobile with rotax "521,2CC" water cooled motor number 3570475, tool kit, studded track, and heated grips, odometer reading 0448. ID number 372902046.
That was a fast year for the 521. !!!!! 40mm carbs stock I think?.? I had a uncle that had one tunnel ported , some rotary valve 5.. something. Head was decked. Pretty sure a set of vm44s . That thing would shut down anything anytime!
I had an 87 Plus, that little 521cc pulled the front end of that heavy PRS chassis right up in the air.
Had a Black 86 , Fun Sleds
That was a fast year for the 521. !!!!! 40mm carbs stock I think?.? I had a uncle that had one tunnel ported , some rotary valve 5.. something. Head was decked. Pretty sure a set of vm44s . That thing would shut down anything anytime!