http://www.klr650.marknet.us/timesert.html

Is this the kit? The Thread-serts I have used were for sheet metal.

I still stand by my original advice. A tapping and drilling guide will attempt to insure that your parallel to the axis of rotation. Knowing where you are working and the limited area, there is a chance that you still end up drilling a little out off axis. Enlarging a hole with a drill can be tricky made worse by cast iron being a bit grabby.

That's why a guide bushing that pilots on the OD of the crank snout would reduce the chance of drilling off angle and off axis.

Also once a hole is off angle, tapping it straight becomes difficult. This is an area where you want as close to perfect threads as possible, with no angle loading

I know the job can be done with just hand tools, including a simple guide bushing, but a guide that constrains all degrees of freedom except the z axis reduces risk. In this case the stakes are very high.

In terms of degrees of freedom the bushing you are getting only constrains the off axis angle. The nose of the drill is being used to constrain X and Y. On an oval-ed out hole can make doing this challenging.

Have fun, drill away, but be really careful.



Kevin