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Is piston rod slop normal?

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I have fragged my motor, apparently from running it low on oil (I know, I know--don't want to hear about it.), and am trying to assess the damage--how far down it goes from the top end, which appears to have suffered the worst of it. It appears that the damage is piston up. But my piston rod has some side-to-side slop on the crank--it jiggles quite freely against the crank lobes on either side of it, maybe 1/8" play at the top. Is this normal, or sign of a damaged bearing at the crank?

In case it might help to know what else is going on: First symptom of an engine problem was rapid tapping/ticking noise from head area for about one day followed by sudden seizure going about 50 mph. Spark plug tip was smashed. Thought it was a thrown piston, but piston still attached to crank, crank apparently intact and turning smoothly. Both exhaust valves broke off their stems and were found lodged inside the recess for one. Exhaust cam cap fractured in two pieces, between L and R fastening points, close to R side. Exhaust cam cap and head both badly scored on L side, where the oil journal goes around the camshaft. Blowback burns in vicinity of left-side exhaust cam cap. Piston face badly gouged, apparently by broken off valve(s) bouncing around inside combustion chamber. Cylinder wall visibly nicked at top, above piston rings at TDC. Some lighter (brown colored) burning or rubbing or possibly very fine scoring on cylinder wall for a most or all of stroke. The piston pin had to be tapped out with a socket--it did not just push out with finger pressure; it has friction rings. Below the piston, except for the browned piston pin area, all looks okay--no metal flakes found. No flakes in the oil, but there were some fine metal particles and molybdenum grease on the magnetic case drain plug.

Apparent cause is low oil--measured 250 ml (out of 1700!) when I drained the oil. I don't know how I did it. I change oil/filter regularly, and nothing unusual happened there--I was not especially overdue. I had not checked the level since I filled it, but assumed it to be okay since my bike stayed clean (no leaky gaskets or bad seals on fasteners) and it didn't smoke and ran fine for about 2,000 miles after the oil change. Is it possible that I drained the oil and replaced the filter during the last change, but forgot to refill the frame with oil? I can't imagine that I did this, but what else? Do thumpers/DRZs typically burn massive amounts of oil? My DRZ was an 06 with less than 10K. I thought perhaps the oil escaped through the exhaust when the valves broke, but there's no residue on/in the exhaust header, canister tip.

Thanks in advance for any suggestions.

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time for a new crank

you need to compleatley tair down the motor becouse you have little bits of rod bairing every ware

this means if you do not get every thing spotluss clean the next crank/rod will be wiped out buy left over bairing

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Side to side movement is normal. Any up and down is not. But.....

2,000 miles since you changed the oil (rec. change interval is 1,000 or less) and not checking it, riding hearing 'bad sounds' from engine, it sounds like time to ship the mess to Eddie. I would not fix the top end without a teardown of the crank too.

One quart per thousand miles is not considered excessive. Some bikes use none at all though. Your bike does not hold two quarts.

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The rod big end bearing sounds marginal plus VERY BAD to tap the piston pin out side loading the rod bearing. Better to use a piston pin puller. I would not trust it now.

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