It's something I'd rather not experience. But why would it happen? Is it from a mis-shift/over-reving? Or something else?

 

It happens when the valve retainers suddenly pop off from mad abuse, now there is nothing holding it up so the only place it can go is down.

 

so then the springs and retainers are first to fail when the head goes?

 

so is there anything you can do to prevent it from happening? What do you mean by "mad abuse"? I rev to 8k regularly and often stay in high rpms for a minute or 2

 

Honda motors are strong and lasts long but the more you rev your motor to 8k the quicker the valvetrain will wear down. Thats reason why most race teams rebuild their motors after a season of racing even though they have the top of the line racing parts.

The only way to prevent this from happening is proper tuning. Each time a new performance part is added to your motor you need to tune it to work in hormony with the rest of you parts.

 

if you have a stock engine thats redline is passed what your revving to...
you should be fine.

it'll take ALOT of reving to do any damage,
and prolly for years of doin it.

or at least thats what i think

 

A flat cam caused us to drop a valve. It shocks the valve train so hard that it knocks the keepers out of the retainer.

 

When somebody says to me that they dropped a valve I assume they mean that they burned one. Dropping or holing (or is it holeing) a piston is the same thing. Maybe I'm wrong. Never heard of or saw a motor where the valve spring retainers came out and literally dropped the valve, that would suck.

 

No, it definitely drops the valve into the cylinder.

 

I'm talking about when the valve actually drops and would hit the piston, bounce around and tear up everything it comes into contact with. I'm not too worried about over reving or mis-shifting (not saying I have god like driving skills, but thats human error and can't really be prevented) I was just wondering what causes it and how I can prevent it.

 

From personal experience Taking stock steel retainers to 9k on a daily basis will eventually cause them to break and drop a valve.

 

so I guess just don't rev higher then teh stock rev limit and you should be ok?