2010 yz450 cam timing


11 replies to this topic
  • eckstine918

Posted April 13, 2013 - 05:17 AM

#1

Is there a way to tell if you have the cams 180 deg out of time? I replaced the piston and cams and did not line up the marks when I took it apart. I lined them up upon puting it back together but wanted to be sure. I lined up the mark on the crank and the marks on the cams (lines not dots, hot cams stage 2) to the out side in line with the head.

  • KJ790

Posted April 13, 2013 - 07:26 AM

#2

The spark plug fires at every TDC, so there is no such thing as 180 degrees out of time. Just line the cams up with the mark on the flywheel and you are good.

On a side note, unlike most bikes, the timing mark on the flywheel does not line up with true TDC, it is about 26 degrees past. The dots on the cam sprockets should be lined up with the mark on the flywheel, not with true TDC. This threw me for a bit of a loop recently.

  • hostile silence

Posted August 19, 2013 - 08:26 PM

#3

I have two marks on my flywheel. One is about a 1/4" wide mark, the other is just a dash straight up and down... the 1/4" mark seems tdc.
Also, my intake cam has 2 dots on it?
2010 yz450f

  • Yama5150

Posted August 19, 2013 - 09:41 PM

#4

I have two marks on my flywheel. One is about a 1/4" wide mark, the other is just a dash straight up and down... the 1/4" mark seems tdc.
Also, my intake cam has 2 dots on it?
2010 yz450f

One mark looks like |-| thats used for timing the ignition, the line that looks like | is suppose to line up with the inspection window when timing the cams. the dots on the intake cam sprocket should face 12 oclock and 3 oclock. The exhaust cam dots should be 9 oclock and 12 oclock. The markon the cam sprocket should be level with the head surface without the valve cover gasket installed.   The mark on the flywheel comes around twice per engine cycle, once on compression stroke and once on overlap. you may have disassembled it on the overlap, just Make sure the cam lobes are facing away from each other when you put it back together, if all the marks line up and the cams are faciing away from each other your good to go



  • grayracer513

Posted August 20, 2013 - 06:15 AM

#5

One mark looks like |-| thats used for timing the ignition, the line that looks like | is suppose to line up with the inspection window when timing the cams. the dots on the intake cam sprocket should face 12 oclock and 3 oclock. The exhaust cam dots should be 9 oclock and 12 oclock. The markon the cam sprocket should be level with the head surface without the valve cover gasket installed.   The mark on the flywheel comes around twice per engine cycle, once on compression stroke and once on overlap. you may have disassembled it on the overlap, just Make sure the cam lobes are facing away from each other when you put it back together, if all the marks line up and the cams are faciing away from each other your good to go

 

That's not accurate for the 2010 and up.  For one thing, the intake cam is in the front of the head, so the marks are aligned in the 9 and 12 o'clock orientation, with the 9 o'clock mark aligned with the gasket flange at the front.  The exhaust cam has only one mark on it, which aligns with the gasket flange at the rear.



  • hostile silence

Posted August 20, 2013 - 01:23 PM

#6

I have a 2010 yz450... my intake cam lobe is at about 1.5 oclock , exhaust cam at about 10.5 o'clock. .. tdc seems to line up with the right side of the |-| , not the | mark

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  • grayracer513

Posted August 20, 2013 - 02:46 PM

#7

The mark resembling an H is the wrong one.  Use the single line mark, which should be just to the right (clockwise) of the other.

 

At that point, the cam sprockets should look like the first image, and the cam lobes should point inward and up, rather toward one another, as in the second image. 

 

sprockets.jpg lobes.jpg

 

Need a manual? http://www.yamaha-mo...uals/index.aspx

 



  • delmas

Posted August 20, 2013 - 06:50 PM

#8

Thanks Grey,  your info is the best.



  • hostile silence

Posted August 21, 2013 - 03:50 AM

#9

So ive been lining it up wrong this whole time...? the single mark, | , seems to be just a hair past where the piston is at the very top of its stroke... the top of the piston stroke seems to line up with the right portion of the "ignition mark"... but ill try it on the "|" mark on the flywheel.
Thanks guys

The mark resembling an H is the wrong one. Use the single line mark, which should be just to the right (clockwise) of the other.

At that point, the cam sprockets should look like the first image, and the cam lobes should point inward and up, rather toward one another, as in the second image.

sprockets.jpg lobes.jpg

Need a manual? http://www.yamaha-mo...uals/index.aspx



  • grayracer513

Posted August 21, 2013 - 06:08 AM

#10

Reread KJ's comment here:

 

On a side note, unlike most bikes, the timing mark on the flywheel does not line up with true TDC, it is about 26 degrees past. The dots on the cam sprockets should be lined up with the mark on the flywheel, not with true TDC. This threw me for a bit of a loop recently.

 

This anomaly is probably related to the fact that the cylinder center line is offset forward of the crank. 



  • hostile silence

Posted August 21, 2013 - 08:46 AM

#11

Reread KJ's comment here:

 

 

This anomaly is probably related to the fact that the cylinder center line is offset forward of the crank. 

I guess if i would have paid a little better attention, i would have got this already!, thanks alot grayracer... this should help lol!!!



  • hostile silence

Posted August 21, 2013 - 07:49 PM

#12

Lined the "|" mark up, fired right up! Well, after I installed new valve shims too... thanks for the advice.

Edited by hostile silence, August 21, 2013 - 07:50 PM.






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