Checking Valves - Have question?

First post but do alot of reading. Couldn't find any past post to answer my question. I have an 06 YZ450 that I bought used, raced motocross last season & finally getting around to checking the valves. The bike ran fine, made plenty of power, but occasionally the bike would be hard to start when warmed.

I went throught the proper procedure at getting the piston at TDC, making sure the I mark is aligned with the crankcase cover. After doing that, the cam lobes are pointing at each other, not away from each other as stated in manual. And the alignment marks on the cam sprockets are on the inside and not on the outside as in the manual.

Is this correct or is everything off by 180*. I can provide pic if needed be. Sorry for the long post. Thanks in advances.

Eddie

First post but do alot of reading. Couldn't find any past post to answer my question. I have an 06 YZ450 that I bought used, raced motocross last season & finally getting around to checking the valves. The bike ran fine, made plenty of power, but occasionally the bike would be hard to start when warmed.

I went throught the proper procedure at getting the piston at TDC, making sure the I mark is aligned with the crankcase cover. After doing that, the cam lobes are pointing at each other, not away from each other as stated in manual. And the alignment marks on the cam sprockets are on the inside and not on the outside as in the manual.

Is this correct or is everything off by 180*. I can provide pic if needed be. Sorry for the long post. Thanks in advances.

Eddie

Your at TDC on the exhaust stroke you need to rotate the the crank 360 degrees then the cams will line up correct.

My advice? take alot of pictures if its your first time doing it and you are not confident. That way you can put it back together and compare, as its easy enough to get it mixed up

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