2000 XR650l Top End Rebuild problems

cam lobes down piston at TDC flyhweel aligned with fixed indexer - sounds like you did all of that. But, did you align the marks on the cam chain sprocket flush with the head?

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if not... the valves will actuate - but at the wrong time and may result in bending a valve stem. I like to dop a short awl into the plug hole to ensure I am at TDC when I install the cam and camchain. Helps to verify the position of the piston in my mind, even though the flwheel indication is correct. Afet I connect everything I turn it over with the cam cover off at least 3-4 times - returning to TDC to verify I am dead on prior to buttoning up. Last thing I do BEFORE installation into the frame, is to adjust the valves on the bench and then with the plug out, turn it over again from the flywheel to ensure it is suckin, compressin, and blowin, gets kinds a wa-pop sound (even with plug out) That way I know when it goes in the frame it is ready to start.

I would ensure your carb is fresh and clean too and that the floats are set okay.

check the sub rockers, because it's a radial design ,the camshaft rockers run on sub rockers that push on the valve in a modified direction. check out a schematic of the valve train online

I am having the same problem. I believe I did everything the manual asked for but am obviously not. I did a top end rebuild and I have it all back together. The PO had a Hotcam and the rockers were melted. I went OEM and put the decompressor back in. I crank and crank and the new rocker arms don't move. I just noticed this today after troubleshooting the electrical. I replaced the pulse generator the other day and looked at the timing chain to make sure it was on-track. Good to go. If I take the valve cover off, make sure the cam lobes are at the bottom, make sure the piston is at TDC, make sure the top cam chain cog is aligned at 9 and 3 o'clock with the top-end, what am I overlooking? I just want to ride.

Is the cam chain ON the lower drive/crank sprocket?

It is. I replaced the pulse generator thinking I had an electrical problem along with the ignition coil. I had the side cover off and the chain is on the sproket and tucked in between the guides. I guess I am going to have to pull the top and see where the disconnect is. I replaced the old Hotcam with an OEM cam. I hope I bought all of the needed parts. I ordered the "Cam Assembly" and the decompression plug and spring. I believe that is all that is removed when the previous owner installed the Hotcam.

While at TDC, I took the valve cover off and inspected the cam. The cam lobes were to the side. I was prepared to take the sprocket off and locked the crank in place to keep the timing mark lined up when i noticed that i could hold the top sprocket with my hand and turn the crank. I shouldn't be able to stop the timing chain from moving with just my hand right? The chain is tight and sounds like it is on track on the bottom end.

obviously the chain IS NOT on the lower gear........

 

 

B

obviously the chain IS NOT on the lower gear........

 

 

B

 

 

That's what I said ^^^

You guys were right. The chain was not on the sprocket. I made the mistake of looking at the chain and guide and not feeling back there and confirming it. The chain tensioner kept enough friction on the chain that it advanced when I turned the crank but slipped when it met some resistance. Thank you for your help. 

Hold it up to the phone so I can get a better look at it.

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