[no bs]

got the wife to show me how to put these on here... I hope!

[TWinOKC]

Wow!  Looks like a lot was going on in there in a very short time.

Thanks for posting the pictures.

[suitcasejefferson]

A broken valve caused all that? Worst I've ever seen. I don't see a single tiny spot on either the piston or the head that has not been severely damaged. You would think that as soon as the valve broke, the engine would have stopped immediately, and not destroyed every millimeter of the piston and head. An engine cannot run with a broken valve and a hole in the piston. Maybe the wheels kept the engine turning for some time if you did not pull in the clutch immediately.

[ace.cafe]

The UCE engine that I have here is the same, or maybe worse.
Same failure. Same damage.

[gremlin]

When did it happen ?  under load on the expressway ?  How many miles on that engine ?  was it the exhaust valve that failed ?

[no bs]

26 feb on a back road between davis and dixon ca, 55mph. that is the exhaust valve(or what's left of it).

[heloego]

Damn!

[Ragmas]

And the sticker and handwritten note that both say, OK.

[no bs]

Damn!

as the son of a submarine sailor and my self a former coast guard seaman i remember using slightly more colorful language.

[heloego]

Sorry. I wasn't Navy. 

[johno]

Great pictures.
Although it seems that the valve has caused that damage, to me looking at other engines in various circumstances I have worked on professionally an hobby wise. That damage actually looks like the results of a detonation of some sort the valve failure a result of the explosion................and then the impact damage.
I wonder what would have be seen if there was a camera within the cylinder at the time of failure

[gremlin]

...... That damage actually looks like the results of a detonation of some sort the valve failure a result of the explosion................and then the impact damage.......

cool !   are we talking dynamite here ? -or- multiple flame fronts in a perfect mixture ?

[johno]

Unusually this wiki link describes it pretty well!
http://en.wikipedia.org/wiki/Engine_knocking

[BrashRooster]

You said you was riding @ 55mph? That was a 2011 right? How many miles? Just curious because I have been riding again like I use to before I was sick. Now that I am doing pretty good I ride a bit faster usually riding 70-75mph on the two lane.  I only have 9000 miles on my C5 but I already have put about half the miles I rode on my bike last year in March.  My bike seems to be holding up damned good considering I take it off road as well.  I almost have it payed off so I have been bike shopping except I am keeping my C5 no getting rid of her I just want to know what went down with your bike just so I am aware of it should something happen with mine.  I really love my C5 I would cry if that happened.

[ace.cafe]

The bike has a top speed of around 80mph. Some of them can't even hit 80, some can hit a little over 80.
In any event, doing 75 is very close to holding the bike at top speed. This is considered to be abusive, unless it is only for a few minutes.
It will reduce the life of the engine, and it 'could' even have a very dramatic result as seen on this thread.
If the engine is not modified to go fast, then it is prudent to consider the cruising speed to be 75% of maximum.