Ideal replacement motor for 70's model argo?

[alaskacody]

Ok everybody I have a ??????? about my argo conquest it is a 2000 all the drive chains have slack adjusters on them except the very front there is none on them is there a way to adjust the slack in them there is not enough slack to remove a link but there is a lot of slack so what do i do

[Mike]

You just have to replace the chain.

[smog]

Snowmobile manufacturer started using high rpm 4 strokes engines; if you can get a used engine with clutch out of a yamaha phazer, if will give you speed and lightweight.