Topic: What is the length of F2 valves? Do these look worn out?

[banzaibob]

4"?  How much is the service limit?  The faces and seat look good as well as the diameter.  However the end of the stems look as if they may have been beat hard.  In fact, the stem shown was so distorted it had to be chamfered before I could remove it.  The surface of the end shows what looks like small perforations similar to metal transfer.

[thirsty 1]

Toast

[thirsty 1]

I'd imagine the adjuster screws are to. Sorry

[70CB750]

Thats what some valves looked like on my F2 head.  Replaced them all.

[MRieck]

I am sure the rocker arm threaded adjuster is equally toasty.

[martin99]

You mean you had to chamfer the end to be able to pull it through the guide? Wow, never seen one flattened out like that before. Is this a ridiculously high mileage bike? Did the valve stem tips lose their hardness somehow? Metal transfer from the rockers?

[thirsty 1]

You mean you had to chamfer the end to be able to pull it through the guide? Wow, never seen one flattened out like that before. Is this a ridiculously high mileage bike? Did the valve stem tips lose their hardness somehow? Metal transfer from the rockers?

I'd say lack of maintenance. When the rocker has to much valve lash the adjuster screw beats the hell out of the valve stem. Once it gets through the hard face things go south quick.