sx4tec

I have just bought a 2002 GTX 4 Tec NA for a $1000. It has 75 hours it, but the motor was described as "blown" when I bought it. Apart from that, the condition is perfect! Just got it home and started tearing the motor down. Found the timing chain snapped, along with both of the rocker arms for the exhaust valves for cylinder 2. I now have the head off, the valves and pistons all look OK with slight marking on the valves for cylinder 2. It looks like the piston knocked them closed snapping the rocker arms when the chain failed. They really are very light marks and don't look damaged at all.
I managed to pull the timing chain out, nice and easy, so I don't think the bottom end is damaged. However there are two tiny parts of the chain missing when you re assemble it.
I will tear the whole motor down as I don't want to leave the chain remains floating around in there.
The questions is what should I take the opportunity to replace while I have the motor apart?Obviously the rocker arms for #2 and the timing chain, and I 'll measure everything else? It has 75 hours on it, I don't want to have to go back again in a few hours more if I don't have too. I have rebuilt a dozen two strokes, but this is my first 4.

JasonZE

i would bet money those valves are bent and wouldnt risk running them,
I would check the rod is not bent (unlikely) and at least do rings and bearing shells while apart. make sure you replace all the bolts that are stretch (torque to yeild) bolts which are rocker bolts head bolts rod bolts and flywheel bolts

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currently riding sxr or what ever has gas in it!!