I have a brand new K181 short motor and one of my W/H Raiders needs a revived engine. All my Raiders have 12hp or 16hp. Does anyone know if I can rebore a K181 block to 10hp ( or even 12hp)? Maybee I need a shorter con rod as well????
K181 (8hp) bore size is 2.938. K241 (10hp) bore size is 3.251. K301 (12hp) bore size is 3.375. As you can see there is over .25" difference which will be to large to rebore the K181 block.
K181 (8hp) stroke size is 2.750. K241 (10bore stroke size is 2.875. K301 (12hp) stroke size is 3.250. The K241 and K301 also use a balance gear setup. Don't feel that what you want to do can be done safely. Maybe these two sites can help you.
