Crank Timing

Newbie here. Did search but can't find the answer here.

I am adjusting the valves. Look through the timing hole to crank and there is 3 marks " I I I " - which one is TDC?. If I line it up on the 3rd mark then the cams are in the correct place (alignment dots at 180 degrees flat with top of case -just like in the manual). If I line it up with the center mark cams are not in correct location - slightly off.

2008 YZ450F - any guidance here ? Not sure why there are three marks, manual only shows one ?

Thanks for your help.

Most YZ's have an 'H' and then an 'I'. You want to line it up with the 'I' in this case, which I guess would be the third line.

screw driver in the spark plug hole.

Look more closely. The first two, from left to right, are joined with a horizontal bar, forming the previously mentioned "H". The third vertical line is the "I", and the TDC mark.

Perfect, thanks. This makes sense. Thank you for the responses - excellent to have a place to come to when taking on late night projects :busted:

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