notes when installing new cam

When I was installing the 03 YZ autodecompress ex cam into my 02 wr426 the manual shows the TDC mark to run from pointer to pointer on the cover. I couldn’t find this mark so I lined up the cams and saw an “H” followed by a small mark that lined up perfect when the cams came into alignment. Has anyone else noticed this and is this the correct mark? I’m assuming it is because the bike runs perfect.

Also the chain looks different when sits on the new cam, almost like it doesn’t sit down all the way onto the teeth. Anyone else notice this?

As a point of reference, I have seen some threads saying you will not need to change the shims. I checked and the gaps were perfect with the old cam and the instructions I have say you will need to re-shim when installing the new cam as it will be off by .1 to .2 mm and the instructions are right on. So if you do this mod be prepared to re-shim.

There are different pitches on the cam sprocket teeth, depending on model or year, I can't remember which. I ordered Hotcams and they were very careful about supplying the proper sprockets. If your chain doesn't look like it's sitting properly you may want to confirm that you have the correct pitch.

The Yamaha part number I installed is 5TA-12180-00-00


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