[m2905]

hello all, i have a 2005 crf450x...had water in the oil and white smoke.....the head was put on without the washers from previous owner and the nuts were not very tight...so i assumed head gasket or warpage

got the head planed and valves checked and new seals installed, and rings...all good... new head gasket installed and now im redoing the valve shims...for some reason the valve shims that i checked and replaced before the head problem were a little tighter on the right intake and exhaust...so i ended up with around .006 clearance on the intake and .011 on the exhaust/.014 decomp...i believe this to be correct

my question is...

what kind of oil should i run in it to flush the old oil out? i plan on changing the oil and filter a few times before adding the proper oil...i am just wondering if i can get away with a cheaper oil just to clear it all out...

what would you do? thank you

[JimDirt]

Welcome to the site !!

You can run any cheap oil as long as it meets the JASO and MA requirements (Wet Clutch compatible if you are also changing the tranny oil) , if the oil meets those specs you can use it .... the viscosity does not matter at this point , so you can run 0-40- ...5-30...10-40 , etc , whatever is cheapest and meets the requirements

I will give you a tip for flushing ......... when you drain the oil , and remove the filter cover on the ignition cover , you will notice 3 holes the cover aligns with , take a air hose with a tube nozzle and using maybe 30-50 lbs of air , blow out each hole till you hear just air going thru the tube into the crankcase , this will push the milky oil down to the pump pickup area that is in the 3 channels , flush out the filter (unless you have several of them to replace each time) and fill the engine with oil ,(check to make sure the oil in the tranny side is clean , not milky as well) run the bike for a few minutes (no more than a few minutes otherwise the bike will overheat) and drain again , tilting the bike from left to right as you get to the end of the flow , and you will find more oil comes out ....... Then , blow out the tubes in the filter area again , repeat these steps till the oil comes out looking like oil and not milk ,you will not be able to do much about the top end channels , so running the engine is the only way to flush the entire system ,,Then ride the bike for a few to let the engine heat cycle and hopefully push thru any milky oil left in the system , then pull it in and drain the oil and blow out the tubes again , and see if the oil is still clear ... if so , replace the filter and fill with the "good" oil , and you should be good to go .... , if not , keep repeating the cycle till the oil is clear .....then replace filter and fill with good oil

[m2905]

thats great news jimdirt, thank you for the info and tips! hopefully get it done next week! thank you again

[JimDirt]

No problem , Glad to help !!

[m2905]

Thax again jimdirt, i just got to it today...running great and fully flushed. I used rotella t4 in it...is was the only one with jaso approved...i noticed that others are running it normally...i was buying honfa oil...but i have half jug left...can i keep using it?

[JimDirt]

Yes , I ran Rotella for a long time .... no issues

[m2905]

Great to hear, this bike has aftermarket led brake light installed , blinkers and vapour tach etc...i cannot get the brake lights to work...do you or anyone have a wiring diagram for this bike....2005 crf450x...im gonna clean up all the mickey mouse wiring now that its running well...or point menin the right direction, thank you again

[JimDirt]

I have the OEM diagram , but it will not include anything about the aftermarket brake light , as the X stock only has a tail/headlight but no brake light

But I can post a pic of the stock wiring diagram from my Service Manual if it helps

[m2905]

That would be great jimdirt, its a place to start, i usually end up disconnecting all addons..then redue then to my liking, so stock is a good place to start , thank you again

[JimDirt]

That would be great jimdirt, its a place to start, i usually end up disconnecting all addons..then redue then to my liking, so stock is a good place to start , thank you again

Here ya go ..