505sxf cam wear

Ok, I bought a 07 ktm 505sxf about a month ago, that appears very clean. I'm not familiar with working on ktms, so I have a few questions. I have put approximately 2 hours on the bike since I got it. It has never started very easy hot or cold (even with it turning over fast with the battery charger). The last time I rode it, It took me awhile to get it started and now I cant get it to start at all (wont even pop or try). The only work I have done to the bike is oil/filter change, clean airfilter. The bike has great spark.  The previous owner claimed the shop adjusted valves right before I bought it, but I thought I should check them to be safe.  I have taken the valve cover off, and got it to tdc and thrown a feeler gauge under the cams. Left side ex=.006 Right side ex=.010 Intakes both were .007. The left side exhaust lobe and follower has visual wear but feels smooth to the touch .  The cams almost appeared too dry to me like they were lacking some oil in the top. I know the exhaust valves are out of spec but shouldn't it atleast attempt to start?  Whats the best way to ensure the top end is getting a sufficient amount of oil (im running moterex 10w50). Also, what do you guys think of the 505's engine performance? Im a little disappointed to be honest. My stock 05 crf450 will eat my 505 from top to bottom.

Did you make sure you were getting fuel and continuous spark into the engine?


If you have fuel and spark then i would check and see if the exhaust cam looked like it was left in the oven too long. Has a bluish tint to it.


You can also just turn the engine over with no sparkplug and fuel cock closed and see if the oil jet is pissing oil on to  the cam journals. 


Did you inspect the filter screens for debris or large metal pcs...

I have verified good spark but have not completely verified fuel yet. It smells like gas after turning it over for awhile.  I decided to give it a little twist real quick to see if I could even get a pop out of it ( blurp of fuel from the accelerator pump, I know the accelerator pump is working for fact). Absolutly nothing, not even a little pop. I also verified that the oil jets are not plugged and that they are working properly. what could cause excessive wear on this lobe?

cam 505.jpg

oil oil,,,,,who cares about running crappy,,,,this engine 450/505 sx xcf has a issue with oil pump,,this is 1st & foremost,,,do a search on this,there's info,,pressure bypass  spring gets weak $1.75 ish,shim the spring with a washer,,,easy fix & replace old oil pump to upgraded plastic pumps,an easy fix,lot of guys replace it every year to be safe,,,ktm has info update on this,,search web,probably find more info on 450,same except bigger piston,cyl,rod,,,,,no oil wastes the cams/bearing,,,,,otherwise a great motor,,,505 kicks A,, i believe motocross action had a article  said the best/favorite  motor,,get that fixed 1st.......carb prob?,make sure clean pilot jet,,bike should start super easy

Thank you very much for the advice. I will try that

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