Bike lost power, ran very rough, now no start

[interfuse]

Yes... but I'd want to make sure I have bad compression before opening the motor.

[Wrider]

You'll also want to check to see you didn't bend a rod or put a hole in a piston.  That high RPM with a non-compressible liquid suddenly stopping the motor is NOT good for it.

[400banditman]

Aight, got the plugs out an the value cover off...engine does turn over, an shot oil onto the ceiling lol...only thing that's weird so far is number 4 spark plug was all chewed up electrode side...gonna keep stripping...stand by

[canyonbreeze]

If the main bearing on that rod went out the piston may have hit the plug.  Not good.

[400banditman]

pictures:

[400banditman]

more

[Squishy]

Ouch...

[Wrider]

Ah shoot, just put some Marvel Magic Mystery Oil in there and you'll be fine!

Yeesh that's bad.  Sorry to see your engine is toast bud.  Time for a new motor or a motor swap.  Personally I vote trying to shoehorn in a 600!

[400banditman]

I would love to fit the 600 in, but I just don't plan to keep her that long...an I talked to a parts breaker in Florida. He said it looked to him as if my number 4 cylinder carb was way rich...cause its the only one that's burned through like that. An there's little play between the piston arm an crank, so hopefully that's not damaged.
No matter happened, I plan to install replacement pistons, rings, cylinder sleeve an ...basically the whole top end. Maybe gsxr cams?
It's all gotta wait tho

[Squishy]

What..no way a 600 would fit?

[Wrider]

Umm bud, you need a new parts guy.  Rich doesn't cause detonation like that, it'd be too lean.  The coloring comes from the oil it ingested.  And I'm guessing since it was (obviously at 100+ MPH) running fine, then suddenly it went kaboom, it was the oil it ingested that caused that damage.

As far as there being play between the connecting rod and the crank.  There ought to be some, but not enough to feel it once the conrod big end bolts are tightened down.

When you have damage that severe it usually ends up screwing up the bearings between the conrod big end and the crank.  Fixing that involves machining and more money than the bike is worth (by a pretty decent margin).

[400banditman]

Yeah I still gotta pull off the oil pan an check for metal

oh an rich, lean, whatever, the point was that mis-...calculated carb settings or whatever did it. Not riding at high speed. although that prolly excelerated things LOL

[Octane]

Wow! I was close. If it were me, and I wanted to keep it, I'd source a replacement 2nd hand engine less all the bits that hang off it.
Take the buggered bits to the scrap metal guys and cash it in. Alot of work and $ goes into rebuilding an engine. If you can get a replacement that can be compression tested all the better. 

[interfuse]

Yikes.

[canyonbreeze]

Keep an eye on ebay.  I picked up an entire 400 engine including most of the ancillary parts (starter, clutch, stator, etc) for $300 + $75 shipping.  I took it apart and found one cylinder had bad rings, otherwise it was all ok.  I coated all the parts in oil and packed them away in freezer bags in storage, long term project.