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250f cam timing question

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I am trying to help my son finish the rebuild of his '09 YZ250F.  The prior owner blew up and repaired the clutch, but didn't bother to clean all the debris out of the crankcase.  A very bad rod bearing was the result.  It now has a new crank, piston/cylinder, balancer bearings etc.  The reassembly has gone well until I got ready to time the cams.  It appears that the prior owner installed an adjustable cam sprocket on the intake side.  It doesn't match the pictures in the shop manual.  The above picture (if it loads correctly) shows the current timing at TDC.  There are 2 dots which I have aligned with the top of the head, and another dot which is straight up at 12 o'clock.  Does that look right to you guys?  The lobes look to be in approximately the correct position and there is no valve to piston contact turning it over by hand. 

 

Thanks for any help you can provide. 

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Looks ok to me, would be good to see the lobe oosition. You ciuld try it on tooth advanced and on tooth retarded and see how wrong it looks, I have done this when trying to second guess myself.

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Possibly a Falicon Adjustable Cam Sprocket.

My experience with adjusting the valve timing is with the old KLX250 4 stroke.  By adjusting the timing, you move the power band up or down in the rpm range.

I have no experience with it on the 250F.

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As long as all the punch marks line up and your flywheel is on the right mark everything should be fine, just turn it over and go through the gears by hand once everythings back together to make sure, did a ktm 450sx once (customer supplied the spares) put it together and only realized then that the head gasket was for a 400 not a 450 and once the timing chain is rivveted together you have to cut it to take the head off and change the head gasket, but thats why I own a yamaha haha

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The adjustable gear allows for cam timing changes. During the building process you can "degree" the cam. I'd figure out who makes the came and see if there is a "straight up" position for setting that cam. If the cam is not positioned correctly your powerband will be off.

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The adjustable gear allows for cam timing changes. During the building process you can "degree" the cam. I'd figure out who makes the came and see if there is a "straight up" position for setting that cam. If the cam is not positioned correctly your powerband will be off.

 

Thanks for the replies.  I couldn't find any identifying marks on the cam, but assume it is stock.  I'm guessing its just the adjustable sprocket that is aftermarket.  I have a lot of experience setting the cams on a DOHC automotive race motor, but didn't want to deal with the hassle of setting lobe centers on this bike if I didn't have to.  We were just looking for the stock settings.  We too it out today and rode for a few hours.  Bike ran flawlessly.  It has a similar power band to my '08 CRF250, so I assume we got it close.

 

Thanks again!

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