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Engine wont turn a complete revolution

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Installing my head with new KW valve train and I cant get it to turn a complete revolution. It binds when the cam tries to open the intake valves., either direction.

Is it possible that the local machine could have assembled it in a way that would cause the intake valves to bind?

I laid the bike over and removed the ignition cover, followed all around the flywheel and inspected the chain, it is on the crank and not binding on anything. The engine will turn over freely until the cam is installed

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I think your cam timing is off...

Motor is stopping because the piston is hitting the intake valves.

Recheck those timing marks and hopefully it didnt bent the valves.

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I havent forced anything so I don't believe any damage is done.

I am not happy with the timing marks, cant seam to get them perfect, like a 1/2 a tooth off.

I'll keep trying, thanks for the help

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1/2 tooth won't cause the valves to hit.

Is it possible the cam is 180deg. Off?

Are the lobes pointing to the rear when your checking the marks?

Are you rotating the engine the correct direction?

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Lobes to the rear, it happens either direction. I checked again this morning when the eyes weren't quite as slanted and it looked perfect.

Odd I remember the crank mark being much more obvious than the only mark I find now?

Not my first rodeo, been in and out of mine several times and a few others as well. This has me baffled.

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That does sound strange, one of the first things I thought of was the chain not being on all the way or out of place somewhere, but if thats good I think I would remove the cam and push down on all four valves by hand to check that they move normally. Did it have a problem before you took it apart?

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The chain was off, feeling it under the flywheel it feels good, looking at it from the top it looks good. Is there a better way to check, should I remove the flywheel? When it was off the cam would not go into the head and now it goes in normally.

If it was off why would it turn 340 degrees?

I will try to push with my fingers.

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If you cant see that the chain is on all the way around then remove the fw just to make sure, also check the little metal gaurd or chain stay just below the crank and chain to make sure its not bent wrong or damaged somehow.

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I can push them open, it is very stiff but they do open. I put a dowel in the cylinder and it is on TDC.

Whats the trick for flywheel removal, will air do it?

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no you need the right flywheel puller to remove it. If you have the stator side cover removed you should be able to see if the chain is on all the way around.

Was there a related problem with the bike before you took it apart or just had to freshen it up? What new parts did you put in it besides the valves?

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Okay here's the deal, I bent the lower cam chain guide. Still don't understand why it will turn 7/8 if a circle but hey, we don't alway understand things in life.

I havent got the flywheel off yet but what I can see with a mirror my tab looks like this;

BikeIssues066.jpg

Thanks for the help, I will advise as I progress.

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thats a good photo and from what I can see the tab and everything there looks normal

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Did you loosen the cam chain tensioner before you took this pic? Or still have the cam out?

The chain looks loose for sure. Just trying to think about how it slipped...

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you can drop the chain down there when the cam is out or head off, BUT DON"T ROTATE THE CRANK till it's pulled back up

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the guide doesnt look pretty but can't see how that would stop the motor from rotating.

The crank will rotate 360deg w/o the cam installed correct?

If so will the cam rotate with the piston at botom dead center BDC?

Not easy to rotate the cam with the springs installed but it is doable with a strap wrench or a spanner wrench. If you have and old chain just use pliers.

PS. when removing the flywheel use the special tool. It protects the crank snout. It is a seal surface for high pressue oil to get to the rod and mains.

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Not my pic, I don't have the flywheel off yet. It is from a different thread. A visual of it looks bent.

With out the camshaft it will turn a complete revolution. If I cant find a puller to borrow today I will order one.

BTW I did find a mystery part in the ignition cover......... I found a dowel from a cam cap! I always keep a close eye on the retainer clips and shims never thought to keep track of the dowels.

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Was the dowel causing it to stop turning or chewed up at all?

If your anywhere close by I would borrow my flywheel puller to you.

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Once when i put my head back together i was just barley off of TDC when i set my head on and lined up the cam and my bike bound up on me just like that. instead of removing the covers and lining up the dots i just removed the head and reset the piston at TDC and put it all back together. Lined up the cam with the top of the head and i was in business.

If you can make the piston cycle by turning the cam chain it should be on there properly. Also i don't think it's possible to get the chain on the cam sprocket it the chain was not properly set on the crank.

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Well I am back to my original question in regards to possible improper assembly of the KW springs.

With the chain off the camshaft (piston on BDC) I cant get the cam to turn past the intake opening. I am using a spanner wrench with 12" if leverage, it doesn't want to move.

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