Anyone else lucky enough to grenade two counterbalance shaft bearings in one year?

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Bought a 97 SPX for my GF to ride. Went through the carbs, new fuel lines, replaced oil with XPS, ran premix in the first tank, all the good shit.

Got about 12 hours of the engine, before she says it's taking a lot of throttle to get up to speed and it's loud. Told her to pull over and pulled the seat off. Smoke, and saw aluminum chunks in the hull. Knew right away, fucking counterbalance shaft bearing.

Same thing happened to my 96 XP in May. What great luck lol. I'm still skeptical how that bearing gets oil.

I think it's only a matter of time they wear out, especially if the engine ever took on water or has high hours. That weight side at the mag end tends to be were it fails. I did the full rebuild on the GSX though it really didn't need it at ~160 hours, and the BS bearing on that weight side was noisy, so I swapped the bearing out anyway.
Really sucks it takes the case with it when it goes. I suppose if you caught it soon enough you could shut it down and rebuild it.
Just discovered that the front (mag) bearing is a sealed unit which sucks. Hopefully I don't grenade another case for at least 10 years
Luckily I’ve only managed to lose a balance shaft once, but that ski did come out of a ditch that it had been sitting in for at least five years... I was pretty impressed that I got as much time out of that motor as I did...
Ouch!!! I sheared the air compressor bolt last month. Luckily the damage was minimal. Engine was about to get rebuilt anyways....
Managed to do one this year on my 951 about a month and a half ago. It snapped the whole shaft, threw case chunks and bearing pieces everywhere. We had gone through a tight shallow passage at idle from one lake to another, ripped crazy fast for my '98 GTX Limited on the next lake, faster than it had ever gone with my girlfriend and I both on it, came back through the passage at idle and it went clunk clunk clunk. I stopped the machine, it started back up and continued to drive the rest of the day. Went back out on the water, took on tons of water and bogged down after about 4 hours. That's when I realized something was wrong. We rode it about another 4 hours after the case had blown open. I feel kind of like an idiot for telling people that, but it was still running extremely fast after this happened until we had a hull 1/4 full of water.

I guess we were lucky it happened at idle and not 7000 RPM. I put a new CV Tech AAB short block in it. Glad to be back up and running, but it just doesn't have the speed this motor had.

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