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Discussion Starter #1
In an attempt to do my own valve adjustment, I hit a road block. I got everything off and went to turn the craftshaft clockwise to make my measurements by aligning the "T" index mark with the notch. My crankshaft won't turn more than 90 degrees in either direction, clockwise or counter-clockwise. In the range that I could turn the crankshaft, it made couple of loud pop and then started to turn until it came to a dead stop. I've removed the spark plugs, the camchain tensioner, and even put my weight onto it but nothing. The bolt would turn but the crankshaft stayed at the same position. Any idea what's wrong?
 

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That does not sound good at all. I hope you didn't damage anything.

Is it possible the cam chain is binding up?
 

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Discussion Starter #3
Possibly but I'm not sure. I guess my next step is to remove the camchain completely to see if it turns freely.
 

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Discussion Starter #5
lol don't do that. if you're not at TDC you could run your pistons into the valves.
Good point but now what?

It just weird that I was able to turn it freely to take the first 2 measurements and then all of the sudden, it came to a stop where I could no longer turn it clockwise.
 

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did you pull the tensioner?
In the first post he says he removed the tensioner.

OP did you pull the tensioner before or after the loud pops and crankshaft halting.
 

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If he's just taking measurements shouldn't the tensioner still be in?

Sent from my XT1031 using Tapatalk
 

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Discussion Starter #9
I turned the tensioner clockwise and used my fabricated tool to lock it in place before proceeding to turn the flywheel. After it was stuck, I then removed the tensioner completely to isolate it from the problem.

I'm thinking of putting it back to see if it can tension the chain and clear any lock up but the manual actually said to loosen it so I don't damage the chain.
 

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If you released the cam chain tension then turned the crank the pops you heard were probably the cam chain skipping over the cam gears

Since it's now out of time it's possible the reason you can't turn the crank is because you are contacting valves with the pistons. Don't do anything more at this point. Hopefully you didn't bend any valves when you "put your weight" on the ratchet.


Set the cams to their tdc position if possible and do the adjustment. then set the crank to its index mark, then re assemble the top end and re time your engine.
 

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Discussion Starter #11
I'm afraid you might be right and I'm too late to read this suggestion. I ended up breaking the bolt to the flywheel and will have to figure out how to fish it out. :frown2:

I'm going to order the replacement bolt and will have the bike going to a mechanic shop to see if it's fixable.



 

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Yes. You did the same thing as he did. And I told him the same thing I told you...


Do you not want to believe this advice?
 

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What a nightmare :(
 

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What a nightmare :(
True. I would imagine the engine will need to come out now to replace some valves. Really a harsh way to get educated about the differences between the traction and slack sides of a timing chain.

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Not good. In automotive terms the engine is an 'interference fit' engine which means the pistons are able to hit the valves if the camshafts and crankshafts are out of time. When you break the crank bolt in an effort to force it to turn over then it's a pretty good sign that there was/is a mechanical blockage preventing the engine from turning over. Any time there is a mechanical blockage or hydraulic blockage - it's not a good thing. I'm sure the mechanic will love you because;

1) You tried to save money at his expense
2) You then promptly broke the crankshaft bolt (among other things)

In all truth, unless a person has a strong background in the automotive trade (or other equivalent) I would seriously consider just biting the bullet and taking it to the dealer before you muck things up. Even people that have 'successfully' adjusted their valve clearance often have the exhaust camshafts retarded. They think it's good but it's not. If memory serves there's even a How-To on this site where the pictures clearly show that one of the camshafts is out of of time. I would not be surprised if many of the bikes out there are like this due to the owner saving money.

Don't get me wrong, it's not like it can't be self-serviced but I used to own an automotive shop, have personally worked on thousands of cars, have probably done a thousand timing belts and I know, right off the bat, that any high-performance engine will have tight piston to valve clearance and this means that the pistons will likely hit the valves if mis-timed. Even knowing nothing about bikes, in that case I would know that the engine is built so close to maximum possible performance that it's very definitely going to be an 'interference fit' engine. There is no other way to extract the maximum performance from a naturally aspirated engine then to have high compression and little valve clearance.

Unless a fella has that understanding and experience going in, it's probably best not to go there at all. My guess? All new exhaust valves and that's assuming a fella can even get the bolt out of the crank. If I had a shop, and someone brought me that mess to clean up, got to say, I would probably send the customer down the road with a sympathetic (and genuine) sadness.
 

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Discussion Starter #18 (Edited)
Thanks for all the help & advice. My attempt was fuel by the fact that I've done it before and in effort to do an updated write-up on valve adjustment to help others who wish to try. I didn't think the forum has so much responses and it could have saved me the headache had I patiently waited for it.

I called the mechanic and he advised that it may be cheaper to replace it with a new engine then to fix. I might just do that. My bike is already at 58Kmi and I could use another engine. Either that or 1000RR.
 

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Discussion Starter #19
Yes. You did the same thing as he did. And I told him the same thing I told you...


Do you not want to believe this advice?
Your advice is spot on. I'm afraid I already mess it up when I said put my whole "weight" on it.
 

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Discussion Starter #20
When you break the crank bolt in an effort to force it to turn over then it's a pretty good sign that there was/is a mechanical blockage preventing the engine from turning over. Any time there is a mechanical blockage or hydraulic blockage - it's not a good thing.
Just for learning experiences, why was there a blockage in the first place? Is the manual wrong by telling me to loosen the cam chain tensioner and then turn the crank bolt? Shouldn't I suppose to keep the cam chain tighten so that the chain couldn't skip a gear?
 
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