This is a GSX1400 Yoshimura ST-1 cam installation.
It’s nice when the cam is exposed like this—the CB1100 SC65 doesn’t have this option, unfortunately.
Remove the holder and hold the bare ST-1 cam up to check for interference, then carefully grind away any spots that look like they might hit using a rotary tool.
Since I don’t want to over-grind,
I go through the cycle repeatedly: look → grind → air blow → look → grind → air blow → look. Many times.
The digital Mitutoyo calipers had a nightmare year-end with both battery terminals snapping off. Analog is the way—much easier to read and refreshingly forgiving.
Each time I hold onto faint hope, install it as-is, and measure valve timing.
As usual, the adjustment is marginal. Grinding itself is quick, but setting up the degree wheel is tedious—though I do wonder which approach is actually faster. I mull over it constantly.
Being off by even one tooth is impossible, so the grinding is minimal.
Since these are inner shims, the clearance doesn’t match.
Remove the cam chain tensioner → remove the cam → carefully extract the small shim → install it in all 16 spots → reinstall the cam → hand-tension the cam chain (it can fly off) → check clearance → often it still doesn’t match, and this repeats several times.
Even if I don’t tighten it that much, once it seats, it’s locked in.
I went with NGK iridium spark plugs.
The right-side damper under-tube has to be shifted to get it out.
It was pretty loose. Good timing for this work.
Stock design, but the configuration isn’t ideal: plastic with metal (aluminum) + rubber + grommets for fastening. Rubber shrinks and it gets loose; aluminum shrinks and it gets loose.
Plus it’s hard to remove—a double whammy of frustration.
Push rivets or well nuts are rock-solid and easy to replace. I’d like to remove the screen occasionally to polish it too.
If the thickness is marginal or you need to gain outer diameter, you can add POM washers.
That’s all for now.
