Bent Valves or No?

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Party time!!!!!

(Except it doesn't let us see the video.... "this video is private."

But I don't think we really need to see it. :)

 
I think I've fixed it such that the video is public. I forgot to click the "publish" button.

Pants is not very good at this Youtube shit.

 
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Glad you got it all sorted out. I think your low reading on #4 was just because you had a cold engine. Should have been done on a warm engine that had a chance to circulate all it's oil..... anyhow, you're good to go!

I'll bet your next valve check will go much differently!

 
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Congrats on a successful check and re-assembly 'pants. Glad to hear everything worked out in the end.

Hopefully the next one is less stressful!

--G

 
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Good job !!! Hats off to you for sticking it through to the end. I am really not sure I am ready to handle a valve adjustment job. Still lots to learn. But this post sure taught me a lot. :)

 
Great news!
I'm betting you know a lot more about valve checks and cam timing than you did a couple of weeks ago.
I was going to suggest you might want to do the compression and leakdown tests but then I thought anything less than excellent results would just make you worry and spoil the fun of riding. That's why I haven't done it on my '07 with close to 150,000 miles. If its good I would be thrilled but if its anything less-than-perfect (and not burning oil etc.) I'm not going to do anything about it anyway; it would just piss me off.. As long as it performs well, that's all I need.

One comment on point #4:

"If I was just checking valves or changing the CCT, I would not remove the timing rotor cover"

I would definitely remove the timing cover for a CCT change. Otherwise, you can't secure the chain to make sure you don't slip a tooth. There have been a number of instances where someone had timing problems after they (or a dealer) did a CCT swap.

 
...One comment on point #4:
"If I was just checking valves or changing the CCT, I would not remove the timing rotor cover"

I would definitely remove the timing cover for a CCT change. Otherwise, you can't secure the chain to make sure you don't slip a tooth. There have been a number of instances where someone had timing problems after they (or a dealer) did a CCT swap.
If someone is changing the CCT I would also advise to remove the timing cover and keep tension on the cam chain. Being off a tooth or two on the cam gears is ungood, but being off a couple of teeth on the crank sprocket can be disastrously bad, that's the fast track to bent valves.

 
Interesting - guess I hadn't thought about that. If you zip tie both cams and release the CCT, you can force the crank to skip a tooth - I know because that is really what started our debacle last weekend. But I don't think you can do it without turning the crank with a rachet. Looking at the timing rotor cover, the right most cam guide is wedged down to the crank gear. The left one pivots on that pin and there is a bit of a gap between the chain and the guide at the crank sprocket. I suppose when you release the CCT, the slack on the chain starts on that left side. If it is going to skip a tooth on the crank, it will do it there.

I do know a lot more about it now. I venture to say I would do it on my bike and other FJRs as well. This morning, I printed this thread and wrote down some more specific notes to keep with my other FJR documents.

El Toro - I understand what you were saying, I just don't agree with it. I do realize that in many things technical, knowing a little can be worse than knowing nothing at all. But for every one of us, for everything and anything (not just valve shim replacement), there was always a first time. Some of us had the benefit of experienced help holding our hand. Some had to do it alone. Some before us blazed the trail, trusting their good sense and judgment would see them through. But if no one ever tried to venture into the unknown (whatever that means), we would be a society of zombies living literally in boxes.

Of course, the other part of the equation is not giving up when the going gets rough. This thing almost beat me down. A younger me might have started waling on it with a dead blow hammer. But I'm getting older now and thinking differently. No one got hurt. The rest is just metal, time, and money. I slept on it, and with some encouragement from our friends, resumed my resolve.

I've never been afraid to try anything. I figure as long as it can't eat me, I'll survive one way or the other. Have I gotten myself painted in corners? You bet. Have I had to pour money on things to correct my screw ups? Absolutely. But more times than not, it works out. I truly hope that I never give up that way of thinking.

 
Good job, 'pants! Y'all ask me how many engine cases i'd split when I tackled my shifter issue a couple of Junes ago. Machines are just devices. Parts go where they go, and line up how they line up. When they don't line up, you find out why. It's not like you need differential equations to undo a bunch of bolts.

There are folks who just don't get mechanical things..... My son was out in the driveway to change the oil in his Miata some years ago. he asked me what needed to be done, and I outlined the process. Put the car up on stands, get the drain pan under it, find the plug bolt on the bottom of the oil pan, which is the big, mostly smooth thing on the bottom of the motor. unscrew the filter, which I'd shown him the location of. Just as I was thinking it was taking an awfully long time and thinking about going out to check, he came in to ask for help, said he couldn't get the bolt off. I go out, get underneath and ask him what's wrong, and he shows me the bolt. He points to one of the transmission mount bolts.

But generally, if you have any kind of mechanical inclination, one kind of machine is just like any other kind of machine, and except for tools needed beyond what's in a general wrench, socket, and screwdriver set, working on one isn't any different from working on another, especially when you have the documentation with you.

I think one issue here was aftermarket manual instead of Yamaha, the difference in markings on the intake versus exhaust cam looks like it might not have been clear.

 
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First off - Congrats to both of you!

Regarding the low compression... I've often seen this. Folks concentrate on problem 1. Have some technical issues so start troubleshooting. Discover 'problem' 2. Go down the proverbial bunny hole with problem 2. Later on, realize problem 2 has nothing at all to do with problem 1. At least that's the way I roll...
smile.png


 
I'm glad it worked out. It could have gone either way. There are a lot of helpful fellows who are willing to share their knowlege on this forum, and that works in favor of those who are adventurous. But you have to be bright enough to benefit, and it appears that you were.

So ... good job, and keep up the good work!

Meanwhile, the machines are worthy of respect. Even if they are just machines.

 
This guy told me that DIY mechanics over think valve clearances way too much. The spec given from Yamaha is a go or no go spec. He said that if at 26,000 miles (for example), you check the exhaust and a 0.007" feeler gauge can fit in (tight or otherwise), then it is in spec and you can leave it alone. Yamaha offers this spec such that even if the lash is at the tightest point of the interval, then it won't tighten enough over the next 26,000 miles to cause engine damage. At the next check, it will need a different shim. But at this check, it's a "go" and you can leave it alone. Forget about this "loose 7" or "tight 6" crap. It's either a go or a no go, plain and simple.
This is very good advice!

 
Interesting - guess I hadn't thought about that. If you zip tie both cams and release the CCT, you can force the crank to skip a tooth - I know because that is really what started our debacle last weekend. But I don't think you can do it without turning the crank with a rachet.
No, it can, and does, happen all the time. I know the chain seems tightly constrained down at the crank end, but that chain is like a mouse. It gets through cracks you would never expect it to fit through.

As you found, if the engine is not at #1 TDC there will very likely be one or more cam lobes depressing a valve. As soon as you loosen that CCT the cams under tension will want to yank the chain one way or the other and it will skip teeth on the crank sprocket. Like I said, this isn't theory. It has happened multiple times before. Yes, you could position the engine at #1 TDC and lessen the chance of this happening, but if you are just changing a CCT how do you know you are TDC unless you remove the timing chain cover? If you bother removing that cover you may as well just ty wrap restrain it (or stuff a socket behind the tensioner guide)

 
I guess it's time for me to enter here and give a big ole THANK YOU to everyone that shared their knowledge and experience with the 2 knuckle heads taking part in this project. Especially to my good buddy, Pants, mostly for not giving up when we were both in that deep pit of despair after that "oh shit, we screwed up" moment.

The guys here are truly a great bunch of obsessive compulsive, FJR fanatics (lucky for us) that really know some shit.

Once Pants did the research and we learned from you guys what we should've known going in, it wasn't too bad.

Virtual, Salute! to everybody.

 
As far as the Haynes manual compared to the Yamaha, the Haynes did show pics and say to align the "Lines" and "Arrows" for the appropriate cams.

When we read it, we just didn't SEE the difference. I read that page I don't know how many times, just didn't pay attention. That and not aligning #1 at TDC, doomed from the start.

 
Did that manual mention keeping the chain taught between the crank to exhaust cam, then taught to the intake? (with all marks aligned)

That, IS critical.

 
Experience is something you don't get until just after you need it.

Learning: what you get overcoming failure

 
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