Which is better for mx, trail, dunes and dragging? Also reliability along with the costs of the two? Thanks

 

for mx, the 686 would probably rev faster and shouldn't lag behind the 720 unless there are long straight-aways. For trails, the 720 is overkill. You wouldn't be able to open it up. Dunes and drag racing, the 720 would probably be the clear winner.


JaMeS

 

i read somewhere about the 720 exeeding the raptors frame capabilities. anyone had this problem?

 

For most people, the 686 is just fine. Stick with the lower compression piston and a mild cam if you want your engine to last and run on pump gas.

The 727 or stroked 760 require a new sleeve, case boring, high perf connecting rod, valve springs, etc.

 

686 is the more reliable way to go, if you go 720 you need to make sure you are working with a quality shop that knows what they are doing (requires sleave for 105mm piston). also for mx 720 is overkill, if dragging is your interest 720 may be the way to go