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350 EXC Top End

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My '15 350 EXC-f approaching 150 hrs...99% single track. Manual calls for a top end at 150 hrs, I believe.  I ride most Saturdays from Dec 1st to Sept 1st, but she sits with a tear in her headlight from Sept 1st through Thanksgiving.  I average about 50 hrs per year on her, run Amsoil 10/50 synthetic and change the oil & filter every 15 hrs.  Wanting to avoid her being down during "riding season", I had planned to have the top end done before saddling back up after Thanksgiving.   However, picking through posts, I find several references where top ends have not been done until well over 200 hrs.  The bike doesn't smoke and runs like a champ.  She usually takes a few pushes of the button to start when cold, but when warm, never fails to fire right up.  Now I'm hesitating to follow through with my top end plan.  Really don't want to dive into the engine prematurely.  We've grown quite fond of one another, so want to extend her life as long as possible.  Will much appreciate thoughts from you seasoned veterans out there. Thanks!

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I can only say I'm 260+hrs on my 350xcf. Most will say that's too far, others might say it's not far enough...Its all where you're comfortable at.

A leak down test is cheap and quick and gives a good idea to where your motors at... 

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No need in my opinion for mandatory head rebuilds.

The manual is very aggressive on this issue and seems to be oriented toward hard core A class riders who race regularly and put there machines thru the wringer with highly aggressive (high rpm) riding.

There are many folks on this forum with literally hundreds of hours on the original heads, with no problems at all. Personally, I'm at 185 hours....(2012 350 XCF-W)....not all that much...but I have zero problems and have absolutely no intention of doing a top-end re-build. I can't think of a single reason to tear apart a perfectly functioning engine that is showing no signs of a problem. A complete waste of time and money IMHOP.

You are 99% single track...(my favorite kind of riding)...so most likely you lug more than you rev....your engine has had a relatively easy life...don't worry about it.

If you remain concerned, doing a leak down test like Monk suggests sounds like a pretty good idea.  That will tell you if you have any issues re the top end...if no indication of serious problems...save your money. 

If it ain't broke...don't fix it!

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