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2014 250f broke a valve..

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hey all, yesterday had a DNF from an engine issue, well got it home and in a couple hours of washing and tear down found out it had broke an exhaust valve... the bike has aprox 260 hrs all together, obviously i never thought about when i should be replacing valves, top end has about 60-70 hrs on it (hour meter fell off and didnt notice for a race or too... oops.)  it didnt damage anything it looks like other than the valve and the piston. 
so onto my questions. 
im looking at all the valve options. i have lapped many a valve and have even done a few 3 angles myself. but i dont know which one i should go with being all relatively equally priced? are stainless just as good? if my titanium lasted this long should i just put oem's back in?
only really asking because i am extremely hard on the bike (3 hour races brutal dust and mud constantly tapped out in 5th.) 
also because ive seen alot of engine carnage but have never seen a valve break like this. 

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Check that the connecting rod is not bent, something had to give when to make room for the valve head.  If you told me you rode tight trail there would be no problem with SS valves, but they are heavier and will not let the motor rev as fast and may cut down on top RPM.  Valve seats should be cut, some automotive shops can do it and may be more reasonable in prices

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Even before I read Rockyracer's above post, those were my thoughts as well :  ' he better check for a bend connecting while he's there '

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1 hour ago, Rockyracer said:

Check that the connecting rod is not bent, something had to give when to make room for the valve head.  If you told me you rode tight trail there would be no problem with SS valves, but they are heavier and will not let the motor rev as fast and may cut down on top RPM.  Valve seats should be cut, some automotive shops can do it and may be more reasonable in prices

but why not a bad valve guide? after being able to pull the valve with the big bur on the top through it with little to no effort i assumed that was what caused the breakage.

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Just curious, stock valves and valvetrain? 260hrs of racing - i would say thats quite respectable for a modern thumper, no?

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12 hours ago, XRalways said:

Just curious, stock valves and valvetrain? 260hrs of racing - i would say thats quite respectable for a modern thumper, no?

yea im not dissapointed in its longevity at all lol but never really thought about life span of valves i guess haha 

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10 hours ago, BIG_FAT_&_SLOW said:

If oem lasts 260 hours that's what i'd buy again.  I know of another one that had over 300 hours on the valve train

true, i was off on my price eyeballing though. difference is apparently a bit more.
i ended up being talked into a pro x stainless by a good engine builder that i've trusted many a time and hasnt let me down. 
side note, getting a 250fx this winter so i only need it for the rest of the season. 

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