Help replacing 07 ktm 250sx topend


I am looking for some help doing a top end for the first time on my 07 ktm 250sx. Normally I would just follow a good "how to" from here or ktmtalk but am really hoping someone with more experience could guide me through it.  I got a topend end kit from Andrew Cooksey (thanks Joe for the recommendation) and am just hoping to get it done sometime before the summer. I live just south of Tacoma in Steilacoom and will happily provide the beer





Is this a 2 stroke or 4 stroke?


does it currently run or are there other problems?


Is it safe to assume if you have not done this you may not be set up too well with tools? micrometers? compression gauge?


I work grave yard and have plans for most weekends between now and June (getting ready for our clubs enduros and poker run) but I might be able to lend a hand if our schedules allow.


I live near the canyon Rd exit of hywy 512

Thanks for the video, I think I could at least attempt it myself first using that as a guide.  


It is an 07 250sx 2 stroke. It currently runs great-zero problems(did look like I had a good amount of blowby last time I had the pipe off).  I have just owned it since 09 and want to do a top end for piece of mind.  Granted, I have barely ridden it during this time as was away at college/residency. I do have a compression gauge and and setup well with tools in general.  Do not have a micrometer but need one anyways so that is easy enough to obtain.  I work a mix of days and evening shifts but mostly 1500-2330 for hours and have a decent amount of random weekdays off.  If you dont mind helping I could PM you with some of my days off and see if one works for you?

Didn't I weld your pipe and subframe a couple of times? I to could also give you a hand if you want. I'm in the Spanaway area

Little Jeff

Yes Jeff that was me!  Thanks again, both have held up perfectly!  With the help of the video I decided to give it a try myself and so far the disassembly went fine.  I am hoping you guys can tell me based off these picture if everything looks ok?  I am not sure the exact amount of hours on the bike as I am not sure if/when the previous owner did a topend.  I have not put very many hours on the bike at all since buying it in 09. 


Are the marks on the cylinder in between the ports normal?  It is perfectly smooth without .  The carbon buildup on the exhaust port seems like a lot to me? Any other thoughts?  











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