I am looking to buy a used cyl for my 86 250R 4 trax and I am have trouble finding one for 86 because it seems that the years 87 - 89 are more available. I would like to switch over to the 87-89 design cause of the better port layout. What would it take to switch my 86 motor over to the other set up? Can I just bolt on the 87-89 cyl? What about the piston? Do I need a spacer plate? What about the shorter rod in the 86 motor? Any info would be helpful

 

switching to the 88-89 cylinder is your best choice. you will have to run the 86 piston due to your short rod, but that is ok because the 86 style piston is the prefered design with its large intake cut away. the spacer plates are for the guys with the long rods running the 86 style piston.

 

Check here - www.macdizzy.com There is a huge amount of "R" info there!