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Discussion Starter · #1 ·
:unsure: Hello everyone. I would appreciate some advice from the community. I acquired a 2013 250 xcf-w that had been partially disassembled by the original owner. (Long story). I am looking to rebuild the top end of the engine and I need a complete cylinder head with cams, valves, bearing bridge etc. I have had no success locating a used head and I cannot afford to buy all the parts individually. I have looked at part numbers for hours and I realize that the only direct replacements would be from a 2012 250 xcf-w, a 2013 250 xcf-w, (obviously), or a 2013 250 exc-f. Does anyone here know where a person might track down this head? Alternatively, has anyone fitted a 250 sxf head (much more common around the US) and had success despite the intake cam and the valve guides being different? At this point, I would consider an entire engine at the right price. Thanks!
 

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2015 SDR, 2010 250xc-f, 2007 wr450f, 2016 Can am Renegade 1000 xmr, 2001 WS6, 2006 ZO6, 2006 GTO
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sir,
Hopefully you purchased this basket case bike for a parts bike price, especially if it is missing the complete head. You will certainly have $1k in the engine by the time you purchase this $585 complete head. I am not certain but i would guess that an sx-f would be the same head with more aggressive cams. Not a waste of time but I have learned that "mechanics specials" on any motorcycle can add up to what it would have costed to buy a functional bike.

 

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First off a caution for you. Purchase of a used 250 4 stroke motor is a dangerous game. If you purchase it cheap with expectation of using it for parts you can get lucky and find one with a rebuildable cylinder head. Most 250 4 strokes are well worn out after a few riding seasons and are ticking time bombs afterwards waiting to explode your bank account. Most of those heads can swap but the SX motors used titanium valves and other valve train parts that are different than your XCFs. No reason you couldn't use either. My advice would be for you to examine your serviceable parts and your parts required to restore your motor/ bike to operational condition. You may find cost of repairs and parts exceed the value of your bike and would be a poor investment. At this point you may find a better plan would be to sell bike as is or strip parts from it and sell them and use funds to purchase a running bike. Check back as needed for help as needed. Good luck
 

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Discussion Starter · #4 ·
First off a caution for you. Purchase of a used 250 4 stroke motor is a dangerous game. If you purchase it cheap with expectation of using it for parts you can get lucky and find one with a rebuildable cylinder head. Most 250 4 strokes are well worn out after a few riding seasons and are ticking time bombs afterwards waiting to explode your bank account. Most of those heads can swap but the SX motors used titanium valves and other valve train parts that are different than your XCFs. No reason you couldn't use either. My advice would be for you to examine your serviceable parts and your parts required to restore your motor/ bike to operational condition. You may find cost of repairs and parts exceed the value of your bike and would be a poor investment. At this point you may find a better plan would be to sell bike as is or strip parts from it and sell them and use funds to purchase a running bike. Check back as needed for help as needed. Good luck
Shield9, Thanks. The bike was bought with the intention to part out if the rebuild is uneconomical. With the current price of these bikes, I could technically rebuild it with new parts and still not have too much invested, but I'd have to do it in stages as finances allow.
 

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Discussion Starter · #5 ·
Shield9, Thanks. The bike was bought with the intention to part out if the rebuild is uneconomical. With the current price of these bikes, I could technically rebuild it with new parts and still not have too much invested, but I'd have to do it in stages as finances allow.
Augiedoggie. Thanks for your input. I understand that the four strokes 'turned a corner' when the twin cams and shim adjusted valves appeared, so maintenance and repairs are on a different level than my old 2002 400exc. I still think that this particular bike is worth repairing. It has been in clean dry storage for about seven years, the damage having occurred at 99 hours and about 1900 miles. I don't imagine that there were many of these built in 2012 and 13 so the idea of finding the used head is fading fast. If I had the original head, I'm almost certain that a company like Fastheads could recondition it. However, the head, cams, valves and followers were disposed of by the previous owner after he was advised that they needed to be replaced.
 

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Discussion Starter · #6 ·
Augiedoggie. Thanks for your input. I understand that the four strokes 'turned a corner' when the twin cams and shim adjusted valves appeared, so maintenance and repairs are on a different level than my old 2002 400exc. I still think that this particular bike is worth repairing. It has been in clean dry storage for about seven years, the damage having occurred at 99 hours and about 1900 miles. I don't imagine that there were many of these built in 2012 and 13 so the idea of finding the used head is fading fast. If I had the original head, I'm almost certain that a company like Fastheads could recondition it. However, the head, cams, valves and followers were disposed of by the previous owner after he was advised that they needed to be replaced.
The
Shield9, Thanks. The bike was bought with the intention to part out if the rebuild is uneconomical. With the current price of these bikes, I could technically rebuild it with new parts and still not have too much invested, but I'd have to do it in stages as finances allow.
Augiedoggie
Augiedoggie. Thanks for your input. I understand that the four strokes 'turned a corner' when the twin cams and shim adjusted valves appeared, so maintenance and repairs are on a different level than my old 2002 400exc. I still think that this particular bike is worth repairing. It has been in clean dry storage for about seven years, the damage having occurred at 99 hours and about 1900 miles. I don't imagine that there were many of these built in 2012 and 13 so the idea of finding the used head is fading fast. If I had the original head, I'm almost certain that a company like Fastheads could recondition it. However, the head, cams, valves and followers were disposed of by the previous owner after he was advised that they needed to be replaced.
Augiedoggie, my understanding is that the valves in these years of xcf-w and exc-f are also titanium, like the sx/mx bikes. That doesn't seem to pose a problem, however, I'm wondering if the different intake cam in an sxf head wouldn't play nice with the EFI or some other system. Thoughts? Again, thanks for your help. Have a good one!
 

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Your 02 400 was a hell of a cool ride. I would own one today if I could find one. Too bad that your previous owner scrapped the old cylinder head but that's probably the reason he parted with it. The good news is there is a healthy amount of blown up 250Fs out there on ebay and in motorcycle salvage yards. The bad news is a lot of them are in poor condition. Hopefully you can source a repairable head and move forward from there. Check crank carefully. I wouldn't hesitate to replace all bearings once a motor destroys it's valvetrain. Metal particles will kill crank and bearings quickly. If memory serves you can substitute stainless valves if you prefer. Cam mix and match is sometimes used with these motors. Some guys switch exhaust cam only to make them bark a bit more on top end. No reason either tune should affect fueling. I would expect your XC ignition might soften the effect of the SX cams if used. The SX is tuned to be more of a screamer.
 

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Discussion Starter · #8 ·
Thanks Augiedoggie. The pickup screens are good, no evidence of any chips or fractured metal. No aluminum sludge and nothing on the drain bolt magnet. I have decided to proceed with a 2011 sxf head from a reputable used parts supplier. I don't anticipate any problems but I will keep you guys posted as to how it's going. I was wondering though, the factory repair manual states that the oil pressure in a warm engine should be 9 psi at 1600 rpm and 29 psi at 6000 rpm. I know it's essentially idle, but 9 psi barely seems enough for the plain cam bearings in the head. Does anyone run higher oil pressure with, say, a longer spring in the oil pressure regulator valve? With so many ball and roller bearings in these engines, the cam bearings sure seem to be the ones that need a little extra protection. I had also thought about having the cam bridge journals treated somehow to reduce friction. I'm probably overanalyzing though.
 

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Good plan. Not to worry much about oil pressure as specified. The trouble with increasing pressure is it also increases work for pump and drive. Engines don't need much pressure at lower speeds because the shear load on parts do not exceed film strength of oil on moving parts. It needs more pressure as speed increases and it is calculated at factory for proper pressure to retain oil film on sleeve bearings and cooling/flushing oil flow on roller/needle bearings. Some builders like to bore and sleeve cam carrier/cam journals with bronze inserts when original alloy journals become galled or scored. No need for this unless journals are damaged. There is virtually ZERO friction advantage over the aluminum cam journals. The cam rotates in a film of pressurized oil and the journal is simply a vessel to contain and distribute pressurized oil. You can be well assured your engineers have done proper study for your engines survival. Most of the engine troubles are owner/rider created problems caused by abuse or neglect. I'm fairly certain from your care and study shown here your bike will be well cared for. No worries here. Simply restore your motor as it was designed and give it good care and it will reward you with good service and performance. Check back as needed for assistance during your overhaul. Good luck
 
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I don't like the twin cam 4 stroke ktm engines. The single cam bikes were 10 times more reliable. The twin cams did go like a shower of sh-t though.
You will find a heap at wreckers, but they will all have the same issue as yours (rooted top ends).
We actually had heaps of the first twin cam ktm's (07-10) blowing up over here, so many of us actually did 2 stroke conversions with old 90's 250/300/360 and 380 ktm engines into them. End up with a frame and suspension that was heaps better and lighter than what the engine originally come out of and a powerful 2 banger.
I personally would cut your losses, but if you want to build it, than happy to help. I will do a little research and see what I can dig up over here.
 
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Sir,
The bike will be worth it. I have an older (2010) 250 xc-f that i have built with a 280cc cylinder and a rekluse clutch that is the most enjoyable woods bike to ride. I know this is an older bike and there have been many improvements made to theses machines over the years but once i have a suspension setup for my ride weight I am reluctant to "upgrade" to newer bikes. My riding skills aren't advanced enough to claim that the bike is holding me back. haha.
 

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Discussion Starter · #12 ·
DW. Thanks for your reply. I agree with you that the single cam four strokes were much more reliable. I don't race or push my bike near as hard as racers do. Most of our riding is following the kids around , seeing a bit of the country, ( North Western United States ) and riding the trails around our camping and fishing spots. I know the two stroke conversion is tempting, but I think staying with the F motor is the best fix this time. Thanks again.
 

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Discussion Starter · #13 ·
Shield9, I'm right there with you. The bike will be way more capable than I am. This will be my first step into suspension with real adjustability, so I'm hoping to do as you have and set sag and damping etc. for the kind of riding that my group commonly does. Onward and upward, as they say!
 
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