Bent Valves or No?

[RaYzerman19]

FSM says 47 ft. lbs. for the crank rotor bolt....... seems like a lot.... wait to final torque it after the engine is all back together, spark plugs in. You might get close. Be happy if it's close.

 

[wfooshee]

1. Ray - in your post #11 - is it your understanding that the orientation of the cam lobes pictured is what the #1 cylinder should look like. IOW - the view of that drawing is looking at the motor from the left turn signal side? If that is true, then the #4 cam lobes would be facing inward toward each other (as in Fred's picture).

Answered above

2. Woofooshee - I'm still trying to understand the "lead" the cams part? If I understood you in post #16, by "forward" side, you mean the side of the chain that is closest to the exhaust header? Keep that side tight when installing the exhaust cam. Then keep the chain between the cams tight as we install the instake cam. Have a got that correct? I'm also thinking that I will zip tie the crank at TDC, then zip tie the exhaust cam after it is installed, then zip tie the intake cam after it is installed, then (and only then) release the cam chain.

Answered above

3. In the same drawing shown by Woofooshee in post #16, there are cam lobes drawn in hidden lines behind the cam gears. Are those the cam lobes for cylinder #1 (I'm just backing up question #1 in this post)?

Answered above

4. Also in the same drawing, on both cam gears, there appears to be some small notches or marks identified by an "A". May I assume that the orientation of the "A" marks ensures that we don't get the cam gears 180 degrees out of sync?

a refers to the holes in the #4 lobe closest to the sprocket. Those holes are straight up on a correctly timed cam when #1 is at TDC on compression, and line up with the arrow on that cap nearby..

5. Trivial question - what does the "E" mean that is stamped on both cam gears?

The E is for "Exhaust." The holes by the stamped 'E' are where the bolts go through the sprocket to attach to the exhaust cam. those holes are empty on the sprocket attached to the intake cam.

6. Can anyone confirm that when the crank and both camshafts are oriented correctly for timing purposes, that at this instant, there are NO valves open (partially or fully)? IOW - are all of the lobes off the buckets? I think this is important. The reason we had trouble in the first place was because we were trying to over come the valve spring(s) to set the camshafts down. This very little amount left no slack in the chain to work. We were able to use the bolts (4 of them) on the cam bearing/block (the one with the lateral camshaft guide built in it) to overcome the valve spring. But it would seem to me that it would be a whole lot easier to set the time if we didn't have to fight a valve spring. If one (or more) of the valves is open (or partially open) when the cams are in time with the crank, can anybody indicate which (and by how much)?

I'm pretty sure one of the cams has valves opening on one of the cylinders 2 or 3, and the other one has the other cylinder with some valves partly open.

7. Bob - in your post #25, you indicate that you learned a trick by "skipping a tooth". Can you elaborate on this, please?

Answered, but I'll add that my term "leading" and his term "skipping a tooth" are the same thing. It's impossible to install the cams with the marks lined up and the chain tight. You either back the crankshaft a few degrees to give the chain enough slack to get the cams in, or you install the cams a tooth ahead of where they belong so that when the tensioner comes down on the chain, they'll back into the correct position.

Once the cams are in and the chain on them, ONLY turn the crankshaft clockwise. That's why you start with the crankshaft backed a few degrees rather than setting the cams forward; gives you space to turn the crank to its mark without having to go all the way around.

8. Finally, thinking positively that we can in fact DO THIS, can anyone provide the torque spec for the crank rotor bolt? There was no lock tight on that bolt, but should we use some and if so, which kind (blue or red). Anybody have a problem with my previously proposed method of torqueing this bolt (bike on the ground in 5th gear, front wheel against a wall, rider sitting on the bike stomping on the rear brake)? Of course the compression of the pistons won't provide enough resistance for me to torque this bolt. If I meet a stop on a stroke, then we know there are much bigger problems than torqueing that bolt. I could use my impact wrench and hunk down on it, but the last thing I need now is a stripped or sheared bolt in a crankshaft. LOL.

First, not sure why that bolt would have been pulled. No reason for it just for the cams.

But since you asked, the manual does not call for locktite there, and the torque is 45 n-m, or 33 lb-ft.

The manual does call for for locktite on the bolts for the pickup coil itself.

 

[RaYzerman19]

Double-checked torque for the rotor bolt..... '06 FSM is 45 n-m/32 lb-ft. but Gen III FSM says 65 n-m/47 lb-ft...... this may be an error, and I thought it high, so I'd go with the '06 spec. I don't see the harm in using loctite.

 

[Mihalis fjr]

hppants,it isn't so easy to bent the valves by your hand and your ratchet,

so don't worry about that..Don't ask me how i know it...

 

[hppants]

Ray - thanks for the clarification re: rotor bolt torque. I removed that bolt in order to remove the chain from the crank during our debacle last weekend. Mike's bike is a Gen II, we will go with the 32 ft. #.

Wfooshee - and thanks to you as well. Your most recent post (ref #4) will be helpful.

Mahalis - I think we will be OK. I called the dealer yesterday just to get some vocal information and advice. Like all of you, they actually encouraged me to continue. The service manager quite matter of factly told me that ".... if you know enough to describe the problem as you just have, then you know enough to put it back together right....". Like many of you, he said that if we actually bent a valve from turning it by hand, that would be the first time he has heard of it (20+ year mechanic). Oh - he's heard of many a bent valve from RUNNING the motor out of time. He's also heard of many a motor in our situation - turned by hand out of time - thankfully, no bent valve stories yet.

Someone please correct me if I'm wrong, but don't the pistons tops for the FJR have recesses in them in the shape of the valves? If so, that definitely helps, IMO. When I pushed a valve(s) against the top of the piston by hand, the entire surface of the valve mated with the piston. When thinking about bending valves, that would be more stable than just touching (lightly banging) the edge of the valve at an angle against the top of the piston.

"It ain't what you don't know that gets you in trouble. It's what you know for sure that just ain't so." Mark Twain

Mike and I are going to give it another try Friday afternoon. Will update as we go.

 

[wheatonFJR]

Drink lots of beer. Say the words, "Watch this..." before you start.

.

.

Okay, maybe not.

But take video of the engine running after you get it back and running...and then crack open that Hamms beer.

 

[Mihalis fjr]

Here are the fjr pistons.Again,it is very difficult or better,impossible to bend the valves by your hand and a ratchet.So,don't worry about that!

The valves are made from a very strong alloy steel!

 

[wfooshee]

They do indeed have the dimples, but that's for how close stuff gets during compression and exhaust and not to clear a fully open valve.

 

[Mihalis fjr]

Yes, ^^^^^ but these dimples can help a lot in a mistake ''by hand,ratchet'' to protect the valves because the slope that they have i believe..

 

[yamafitter]

Placing a straightedge across the head will help you see if the alignment marks on the cams are in the correct position. It just helps reduce any parallax issues and a really good flashlight (or torch for our friends across the pond) is a good tool to have for this task.

 

[DezzertRider]

Out of all this comes some positive learning from a negative experience........ one knows what to do next time or on your first valve check/shim change. While checking your valves, you're spinning the engine, taking your readings, or perhaps taking a second set of readings. If you are going to change shims, it is best to spin your engine to leave #1 at TDC, crank and cam timing marks aligned, cam chain tie-wrapped at crank and at sprockets, loosen CCT, proceed with shim changes. With the cams back in, it is then easy to verify the timing marks are all still OK at a glance.

I just did my first valve check and set the cams aside only. I only removed the cams when #1 was at TDC and the alignment holes were aligned with the arrows on the #3 camshaft caps. I never spun the motor unless the cams shafts were back in place and the alignment holes lined back up with the #3 camshaft cap marks. If you remove the cams and then spin the motor, then you have a whole new alignment issue.

 

[wfooshee]

Yes, ^^^^^ but these dimples can help a lot in a mistake ''by hand,ratchet'' to protect the valves because the slope that they have i believe..

Not much. Those dimples do not clear the valves if the valve is actually open from a mistimed cam (i.e. cam chain skipped some teeth.)

 

[Intech]

Out of all this comes some positive learning from a negative experience........ one knows what to do next time or on your first valve check/shim change. While checking your valves, you're spinning the engine, taking your readings, or perhaps taking a second set of readings. If you are going to change shims, it is best to spin your engine to leave #1 at TDC, crank and cam timing marks aligned, cam chain tie-wrapped at crank and at sprockets, loosen CCT, proceed with shim changes. With the cams back in, it is then easy to verify the timing marks are all still OK at a glance.

I just did my first valve check and set the cams aside only. I only removed the cams when #1 was at TDC and the alignment holes were aligned with the arrows on the #3 camshaft caps. I never spun the motor unless the cams shafts were back in place and the alignment holes lined back up with the #3 camshaft cap marks. If you remove the cams and then spin the motor, then you have a whole new alignment issue.

Wait! A valve clearance check is done with the cams INSTALLED. Why would you set them aside?

 

[Constant Mesh]

You can easily check the cam position using a simple right triangle. The camshaft caps with the alignment arrows have a vertical line extending out on the side next to the cam lobes with the alignment pips. Lay the right triangle down on its side atop the cam lobe with one edge against the side of the cap with the right angle corner against the vertical line on the cap. See where the lobe pip is relative to the edge of the triangle. If everything is correct the pip should just be visible at the edge of the triangle.

You don't need to look at the marks on the sprockets just use the cam lobe pips.

With the triangle down on the cam lobe it's easy to see the pip's location with very good precision.

 

[Mihalis fjr]

Yes, ^^^^^ but these dimples can help a lot in a mistake ''by hand,ratchet'' to protect the valves because the slope that they have i believe..

Not much. Those dimples do not clear the valves if the valve is actually open from a mistimed cam (i.e. cam chain skipped some teeth.)

Agree if the engine runs!But if you turn the engine by your hand and if there something is out of alignment,these dimples can help to absorb some force from the pistons to the edge of the valves..My opinion.

 

[hppants]

C/M - I'm trying to picture what you have described, but it's not clicking. It sounds like you are suggesting a way for me to verify correct timing without having to look at the alignment marks on the outside of the cam gears. This is desirable because, as you know, seeing the gear alignment marks with the engine in the frame is difficult at best.

What is an "alignment pip"?

A picture might help, although you might not be able to provide one.

Regardless, I'd just use this as a triple check to the traditional FSM method. Transferring the marks to the inside of the gear will definitely get me within 1/2 of a cam gear tooth, which is accuracy needed to meet the objective. I can then use a dental mirror and head light to verify the actual marks on the outside of the cam gear.

Mahilis gets what I was suggestion re: piston tops. It's an interference motor - one revolution at speed and it's grenade city. But just turning by hand, I'd rather have a valve touch (or lightly tap) the top of the piston across the entire diameter of the valve than have it only touch one point on the circumference.

Obviously, I don't trust anything in the Chilton's manual anymore. Can anyone please verify the torque spec for the cam bearing caps as 88 inch pounds?

Also, what does the Yamaha FSM say regarding compression test pressures? I realize that if I have a bent valve(s), the numbers should be proportionately lower in that hole(s), but I'd like to know what is considered normal?

I really feel that I have a true understanding of this now. I definitely know what I need to do. Hopefully tomorrow, we will have some good news.

 

[Fred W]

Pips = the dimples in the back of the #4 right-most cams that I posted a picture of previously. Those holes can be used to confirm the proper cam timing, but I would also attempt to use a mirror and view the marks on the right end sprockets.

Two alignment checks are better than one.

 

[El Toro]

Pants, the more time you throw at this to try to fix it yourself, the more money you will have to pour on it later.

The questions you are asking, and the follow up questions that you are asking, indicate that it is not really fair to the owner of this bike that you continue to work on it.

Find a dealer with a good mechanic and trailer it to them.

The bad news is that this is their busy season, and the bike may have to wait for some time.

The other thing you could do that might be fair to your friend is accidentally back over it in your driveway ... of course I'm kidding (wink, wink, wink), but you get the picture.

You're two torque wrenches away from owing your friend a bike, and you can't dig out of a whole with torque wrenches.

 

[Constant Mesh]

Fred's photo shows the pips, small holes in the intake and exhaust cam lobes, visible between the long camshaft caps and the chain sprockets.

You can see one intake and one exhaust cam lobe between the end of the long caps and the sprockets.

If you had a reverse view of Fred's photo we could see a vertical line on the end of the caps adjacent to the cam lobes with pips.

The side of the cap is flat and perpendicular to the camshafts. There's a vertical line in the center protruding out just a bit from those flat surfaces. If the timing is correct the vertical lines with align with the pips.

If you lay a thin flat object like a right triangle or any object with two straight edges with a right angle down on top the cam lobe, push one of the edges up flat and square against the cap and slide the right angle corner against the vertical line on the cap you can easily and precisely eyeball whether the pip is aligned correctly with vertical line on the cap.

With the triangle down touching the lobe you can eyeball the pip's location with great precision.

I believe there are 38 teeth on those sprockets so a one tooth timing error would be an almost 10 degree error of misalignment for the pips. A 10 degree error is very easy to see with the right triangle technique.

 

[Big Sky]

This thread reinforces some things for me. I have much respect for Pants and others on this forum. If it's troublesome for Pants, I sure as hell am not even gonna try. Besides, many years ago I tried checking valves on a 750 Sabre (screw-type adjustment but four cams!) and wound up taking it to the shop to get it done right. Lesson learned. I have not attempted it since and have no inclination. I admire and envy the folks with the ability to do these things, but I respect those, too, who know better than to try it.