Head/cam Install Help

[400ex2072]

Getting my engine back together and have a question. I have installed a new 12.5:1 piston. With the much larger dome on the piston, I was wondering if there are any precautions I need to take? Also, I have a service manual, but it doesnt say anything particular about putting it back together. Just how to do it in order. Doesnt say if the piston needs to be at TDC, or what stroke, or anything. I dont want to crank this thing over and bend a valve.

I have the lines on the cam sprocket lined up correctly, but havent reinstalled the bolts to the cam yet until I find out if I need to change the stroke/position on the piston first, at which point, Ill realign it. Head is already installed, just curious as to this cam setup, and getting the timing right, which I know is the most critical make or break point in this process!

[2muchquad]

yes the piston will have to be at TDC,then you'll have to align the marks on the cam with the surface of the head.im sure your manual shows this procedure.good luck:)

[terko440]

Also, with the piston at TDC, you will have all four of the lobes on the cam facing down while installing.

[400ex2072]

hey thanks for the replys everything went together smoothly and turns over great by hand. Just one last question. When I turn it over by hand there is like a click coming from the area of the right front exhaust valve on the compression stroke. This is due to the Decompression mechanism correct? Im pretty sure thats what it is, but Ill wait on getting the engine back in the frame til someone confirms this. Everyones help is really appreciated, this aint the #1 atv site for no reason!