Sprocket alignment runout

[theiceman]

As I am doing some work on my car I went to my buddies house who is further ahead doing his. To try and learn a few things.

He we went to show me the measurement against the inside of the sprocket on the left side as he had out his tensioners back in. he me measured it on the outside and he was 10 thou off .. WTF !!!

so we took the tensioner off and discovered there was 10 Thou difference between the inner measurement on the sprocket and the outer. The stromski tool is set up so you can measure both sides of the sprocket so it was easy to see without moving anything.
As a further example ( just as an exercise) we saw a greater deflection on the chain housing. although not a recognized measuring spot we were demonstrating the same phenomenon.

So we switched it over to measure the right side .. The opposite phenomenon was observed which made sense and confirmed our findings.

On the drivers the closer side of the sprocket to the centreline on the case was 10 thou closer than the outside.

On the passenger side the closer side of the sprocket to the centreline of the case was about 6 thou further away than the outside.

This caused us to suspect either the tool was running out , or the webbing on the case we were measuring against was out of alignment.

Was really fascinating so i thought i would ask here in case anyone has run into this .

As our options were limited we ended up putting a two tho feeler guage between the tool an the passenger side of the case when we attached the stormski alignment tool. This squared up the tool to the case and everything matched. Then we were able to redo our shimming. Then we called it a night while we thought it over.

The case is pinned and glued so there is no going back now, and doubt there is anything we could do anyway .

Any thoughts on this ? i found the whole exercise very educational on how all the measurements inter relate.