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cam timing problem

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Here's the short version so far: 04 250R, four new valves, springs, stem seals, piston, rings and gaskets.

All timing marks line up (this is the fifth time I have done this, and all the others ran great).

As I kick it slowly, it comes to "soft" stop just as the intake valves are opening. It will not turn over past this spot.

The piston is in correctly.

I torqued the head down then removed it to align the front tensioner, then torqued it back down a second time.

The cylinder is not full of any fluids.

It will kick over nicely if you have the cam out of it.

The only things I can come up with: Cam gear slip? Twice-torqued head gasket and base gasket too thin now? Too much tranny oil? I'm pulling my hair out over here!

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Make sure the motor is at TDC. Then double check that the cam is at TDC on the compression stroke. Is everything shimmed correctly? Sometimes if you mark the chain and a mark on the sprocket the timing chain can slip on the rank gear and wont line up properly. :cry:

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Make sure when you line up the marks on the cam that the intake lobes are pointing to the rear of the bike :cry:

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Possibly bent valve or improperly installed valve guide?

When you say it kicks over easily with the cam off, I assume you have the plug out to release compression. Try putting the plug in and see if it still kicks over. If it does you know you've got a valve hanging open or stuck part-way.

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Thanks for the help guys.

The lobes are to the rear, both the right side primary gear marks and the "T" on the left spot on. The lines on the cam gear are right on the top edge of the head. When I move the kickstarter, just as the intake valves start to open, it locks up. The only parts I removed were the valve cover the spark plug.

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Oh.. I worked real hard to make sure I had .005 intake and .011 exhaust.

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The only other thing I can think of is the chain came off the gear down on the crank. Pull the left cover off and check it out. There is a tab down there to keep it on but it doesn't really work so good. This is only if you took the cam out which I'm not sure from your post if you did or not. If you just checked your valves and it was running before,,,,,, hmmmm :cry:

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Mine did the sme thing when I put my 250 R cam in, but I had ended up bending my valves, make sure that your cam chain is proporly seated on the crank If not it will slip off and you timing will change, If your timing changed when you cranked it over this is what happend.

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GOT IT!!!

It turns out that I put the valve springs in incorrectly. Damnit...If you put the exhaust springs on the intakes, the cam will not open them. Got in a hurry and dumbed up.

Thanks again for the suggestions.

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