I am mechanically inclined, but working outside of my realm. My nephew has 2011 Honda CRF150R dirt bike. He decided to do his own own change. He seemingly drained the engine oil, then filled the transmission oil. He proceeded to ride, it quickly locked up.it would not kick over, then eventually did, but no fire.
I have taken it apart, expecting the worst. Right away I found a broken piece of cast, sitting atop the head, below the camshaft. I found the casting in the cam holder was broken. I took the head off and it looks ok, no cont
act or issues. The cylinder wall still had slight oil, and piston looks ok. I did not remove the cylinder as I do not see a need to as of yet.
The camshaft looks as it got hot, but lobes look OK in my opinion. Should I just change the cam holder? I have attached a video I found where the gentleman had the same concern, and exact same piece missing/broken. He changed the cam and mentioned it is not at the correct location when set at top dead center. This makes no sense to me as the cam is directly bolted to the gear.
Similar video: https://youtu.be/Qn4k4yuSk9I
Your opinion and help appreciated. Trying to fix on the cheap
Have a look at 1.15 of the video it looks as if he's placed the bolts in the wrong holes possibly?
The other 2 holes definitely look like they have had bolts in them previously.
Your cam is roached. Also, the cam sprocket bolts to the 2-bolt flange part which is pressed on the cam. Yours has slipped time. Just like the gentleman in the video. And, your valves may have contacted the piston, just like the video.
Thanks, valves and piston look good luckily. I don't think I got the full story from my nephew. So new cam and holder? The lines all line up at TDC etc. Yes the ca looks as it got hot, but I don't see worn lobes etc, so what would it even change? Thanks
Like FGR said - the part that the sprocket bolts onto is pressed onto the cam and can spin, if the cam locks up in the journals. This throws the timing of the lobes off.
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This is why I reached out. Thanks! Figured was all one piece. Off to the dealer tomorrow, hope I don't go broke haha
Good luck! And make sure your nephew puts enough oil in it when doing an oil change, and make sure the filter is installed correctly. Make sure the oil pump is getting oil to the head before running it too long when you first get it going also. Most bikes have a check bolt in the head that you can loosen and see oil come out when its running. Don't want to see your brand new parts seizing up again.
Where is this bolt. To me, looking at rhe head etc, the only way I see oil getting up there is slinging off the chain almost like a chaincase.
So i just looked at the 150r head again, and it doesn't look like it has a check bolt like other bikes do. but oil is pumped thru a very small passageway next to the intake/timing chain side head bolt. It goes thru the cam cap to lube the cam when it is running. Take a closer look at it. Since there is no check bolt, i would run it for a few minutes, and then pull the valve cover to make sure there is plenty of oil sitting in the head afterwards.
I bought one for my son in same condition. Look at the oil filter, I'd be willing to bet it is installed wrong.
I will check that, bought th oil and filter today actually. For the cam, holder and bearings my dealers wants almost $600 CAD. Anyone have any suggestions? I'd prefer it all assembled (cam, holder, bearings). I saw that lastnight on ebay or something but cannot seem to find now. Your help sourcing is appreciated
It might be easier and cheaper to ship a whole head from the states over
Could be, but would that be included, as the head sits below the cam holder and seems separate. Any options seem better
I'm not sure the exchange rate For CAD to U.S. but those parts are about $400 retail.
Looks like your nephew better get himself a job.
I own him this summer by the looks of it haha. Can clean my race car and cut the grass lol
try rockymountainatvmc.com or motosport.com. OEM parts finder. Not sure if they ship to Canada tho?
Thanks. Once all together, I have an oil question
I see it suggests 10w30 or 10w40 4 stroke oils
I have some Lucas oil 10w40 for my street bike. I'm assuming I ca use this with no concerns? I know on my street bike I'm picky with shifting and I can notice different oils
Just use a good quality oil. From what i remember, the 150R has seperate oil fillers for the crank/cams, and another filler for the transmission/clutch oil. They seperate it to keep the clutch debris out of the crank/cams. Just use a quality oil - 10w30 in the winter / 10w40 in the summer.
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