Yz400f Help Needed!

hey guys.me and my dad are getting the motor put back together but the timming chain dosent want to go around the cams! it seems like it is too short! somebody please help! is there a way to putting in the cams with the timing chain! HELP WOULD BE GREAT!

Have you tried going to the yamaha site and looking at some part diagrams? just a thought.

ive got the whole book! this frickin wierd!

Don't feel bad, I had to ask how to do this once also. Put the chain on the intake sproket (Make sure to align the dot with the head suface). With the chain OFF the exhaust sproket, line up the dot w/ the surface of the head. Pull the chain up next to the sprocket (keep the dot lined up on the head) Visually look and see what tooth will line up with what tooth on the chain. Hold those two next to each other and pull the cam/sprocket out of its bore. Now pull the cam assembly back towards the intake side. Put the chain on the sproket (making sure to keep the teeth where they should be). At this point, the intake cam should be aligned with the head surface, the chain should be on the intake cam, the chain should be on the exhaust cam, and the exhaust cam is almost above the intake cam. Still follow? Good. All that is left is to roll the exhaust cam down into its bore. If you kept everything aligned, it should be perfect. Cowboyona426 was who helped me on this about a year ago, so thank him. Jason

ive tried this but the chain is way tight.i dont know what the hell is going on!

I'm sure you have checked but is the chain tensioner taken out? also, make sure the chain is not bound up below on the small crank sprocket.

yes and no its not.time to do it alllllllllllllllllllllllllllll again. thanxs guys for trying to help!

Is the chain kinked in the bottom?

nope its not kinked

I would roll the engine over slowly with the chain supported across your hand, and make sure all is straight. I wish I could help you further, but thats all I can think of.

I think you have a kink in the chain at the bottom sprocket. Take the cams out. Put tension on the chain and slowly roll the motor over and see if you get some more slack. If there is a loop of chain at the bottom rolling the motor over should relese it.

Otherwist its kinda tricky to get the chain on both cams. I put the exhaust cam in 1st with the chain on it. Then with the intake cam out of the journals and angled up at the non gear end put the chain on it. Then rotate the cam down and into the journals. After the 1st time you do it its easy after that. You just have to get the steps down.

But definately check for a loop of chain at the bottom. If you can pull the flywheel and stator so you can visialy verify that the chain is on the bottom sprocket correctly.

Oh any I asume that you have removed the cam chain tensioner. You wont get the cams installed if the tensioner is installed in the motor.

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