[lennie]

bigred,

The difference is as follows.

I now have the sprockets manufactured with a new CNC machining process.

As part of the original manufacturing process, the sprocket locating pin holes were reamed oversize of the 3mm required for the pin due to the fact the hole shrinks when heat treated.

The new CNC process lacked this step and after installing the pins they have a small crack between the location pin hole and the cam mounting hole. There is nowhere for this crack to propogate as it stops at the mounting hole.

I have redrilled the holes to the 3mm and the locating pin fits without causing the crack to open at all. The drilling removed 2 thousandths of an inch. The hole being undersize by this amount was enough to cause the crack due to the proximity to the cam mounting hole.

Once installed, the sprocket mounts to the cam, the locating pin and sprocket are covered by a large thick washer under the mounting bolt and this sandwiches the sprocket to the cam and there is no possible way for it to cause any issues.

I sell these at a discount price of $140.00 AUD and I can guarantee that they will not fail during use.

I have sold many sets of these to date without issue.

I discussed the issue with the original machinist, the new manufacturer and a metalurgist friend and we decided that now they have been drilled to 3mm and with the sprocket clamped to the cam, there is no issue with use.