What is the crank run out issue with gear drive cams? What do people like better. Gear drive cams or the new upgrade to hydraulic cam chain tensioners.

 

Manufacturer states that gears shouldn't be used if crank run-out is in excess of .003. What do people like better? That's a matter of opinion, but in '07- later bikes, most will tell you that there's no reason to switch to gears. The hydraulic tensioners are way better than the old spring style tensioners.

 

The issue is that runout that exceeds .003" (total) exceeds what gears setup at the proper lash can comfortably accomodate. IAW, when you setup a set of gear drive cams and crank runout is out of spec, it will be impossible to setup the gears and maintain the required lash through a 360* rotation. The gears will be loose at one point and tight 180* later in the rotation. This condition will be noisy and if the tolerance is to tight, or the crank should shift another .001", the gears can break.

There are two options for the early models. You can convert to the '07 up full hydraulic tensioner and roller chain setup but this will require a cam change; the old cams won't work in the new cam plate.

Or, you can go the "hybrid" route with the billet plate, upgraded oil pump, hydraulic tensioners front/rear, outer roller chain but old Morse inner chain. this will allow you to run the older cams.

Either chain drive setup will tolerate more crank runout than a gear drive setup.

 

Thanks I get it now.