Chain's still "jumping", now what?

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jimmstr17

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I've adjusted the valves, replaced the CCT with the "blue dot" model and replaced the cam chain on my '05 with 62,000 miles thanks to all of the help on this forum. Unfortunately, at cold idle speed I can almost "see" and can surely hear and feel the chain jumping around. I have also tried the 20W something oil as opposed to the 10W something oil as suggested. I am afraid to run it anymore and hope someone can give me a clue what to do now. I really, really like my bike, but am afraid to ride it as it seems to be a time bomb. Please help!

Thanks,

Jim

 
What do you mean "see?" You can't watch the cam chain with the engine running.

If your idle is low, the bike will sound yucky, but when cold you should have at least a couple thousand RPM at idle from the cold start system. When warm, should be 1100 RPM.

If you're not getting fast idle when cold it's gonna be really rough, but it doesn't have anything to do with the cam chain.

 
Sorry, I guess I meant "visualize. Cold idle is probably 1500 to 1800 then when it hits the first bar it settles down to around 1100. I seem to get small spikes in the rev's as it sits and idles.

 
Jumpy chain means worn out sprockets (not very likely), or low tension. Pull the right cover and see what's happening, won't take you very long and you need to know. Maybe your tensioner isn't in right. Leave the ignition key in the off position until you look.

 
I pulled the cover to double check the tensionser was doing it's thing. I worked the cover off without pulling the retainer pin and found the chain to be tight. I almost wish I found something awry. I thought about sprockets being worn also but haven't heard any mention of changing sprockets in any of the related threads. When I removed the old chain I compared it with the new one before installing by draping both of them over a pencil size rod and could actually see the old chain had stretched as compared to the new. I new I had the fix at that point but after reassembly it still seems like the chain is trying to jump. I'm now leaning toward the APE manual tensioner, although according to the survey, most people feel the new model Yamaha CCT can be trusted.

 
I haven't seen you describe anything about this that says cam chain problem except for noise at cold idle. An older chain will be "stretched" compared to a new chain; that's normal. If it wasn't normal we wouldn't need tensioners in the first place.

Your cold idle is much lower than mine. Stone cold first-thing-in-the-morning my bike runs at 2200 RPM. Hold the idle at 2200 with the throttle and see if your "symptoms" don't go away. A slow cold idle will be rough-sounding.

Personally, I don't think you have a problem.

 
I am only guessing but could it be off a tooth in timing? Can a CCT be over sprung or stuck? I am curious about why your cold idle is not kicking in? I am not sure of the FJR and it's oiling system yet but I would be concerned not getting oil in the quantities needed on cold start up at low rpms. You were sure of your bucket swap on your valve settings? You got a damaged plug? What shape or where did the gas in the tank come from?

I guess I am asking was all the work you did in "one" session and you got it all buttoned up and this is what you are finding?

 
I started with a valve adjustment. Found the two outside exhaust valves "tightened up" just beyond spec. so I pulled the exhaust cam and replaced the shims on the two valves out of spec. At the same time I replaced the CCT (per the advice of the forum). I painstakingly reset the timing and checked and double checked to make sure all was good before reassembly. After this operation the "noise" reared it's head again after just a few thousand miles (I made a quick trip to Kentucky and back for a family reunion). I then decided to replace the cam chain (again with great help from the forum) went through the arduous task of timing both cams to match the crank - not fun, but a worthwhile venture - checked, double-checked and felt good about buttoning her back together. Immediately at initial start-up, cold idle at around 1800 rpm, I hear what I still think is the chain jumping. I tried it again this afternoon and it seemed to make just one "jump" noise before it warmed up to I then II bars and continued to idle along at 1100 nicely. You guys are starting to make me think I'm looking for trouble that doesn't exist. I did put in a fresh set of plugs during the inital valve adjustment as well as a fresh air filter. I just looked at my records and haven't sinked the F.I. since 49,000. I plan on checking that tomorrow morning.

Thanks to all for the help and advice.

Jim

 
Jim, stop posting to the forum and start riding your bike more. You don't have a bike problem.

Here's the thing, the cam chain is not under significant load at idle. It's going to have tiny 'jumps' and make a little noise. The FJR engine is well known to be a tad noisy in the first place. Under load things settle down and it's a non-issue.

You've done a ton of non-necessary work. If you put a manual cam chain tensioner on your bike, you will destroy your engine. Not because of any fault with the manual tensioner, but because you will over tighten it attempting to correct a condition that isn't a fault.

If you're really all that paranoid about this still, go find a 5 star rated Yamaha mechanic and have them look at it. They will likely have seen far more FJRs than you have and can tell you it's fine, or not.

 
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I started with a valve adjustment. Found the two outside exhaust valves "tightened up" just beyond spec. so I pulled the exhaust cam and replaced the shims on the two valves out of spec. At the same time I replaced the CCT (per the advice of the forum). I painstakingly reset the timing and checked and double checked to make sure all was good before reassembly. After this operation the "noise" reared it's head again after just a few thousand miles (I made a quick trip to Kentucky and back for a family reunion). I then decided to replace the cam chain (again with great help from the forum) went through the arduous task of timing both cams to match the crank - not fun, but a worthwhile venture - checked, double-checked and felt good about buttoning her back together. Immediately at initial start-up, cold idle at around 1800 rpm, I hear what I still think is the chain jumping. I tried it again this afternoon and it seemed to make just one "jump" noise before it warmed up to I then II bars and continued to idle along at 1100 nicely. You guys are starting to make me think I'm looking for trouble that doesn't exist. I did put in a fresh set of plugs during the inital valve adjustment as well as a fresh air filter. I just looked at my records and haven't sinked the F.I. since 49,000. I plan on checking that tomorrow morning.

Thanks to all for the help and advice.

Jim
Thank you for the detailed description of events. Seems like you understand your bike pretty well about now. I am beginning to think what others are telling you is so. I do not have a FJR ear yet. I mean people are saying about noise and I think every bike has "characteristic" sounds of it's particular configuration or version. So if these guys are telling you no worries I would listen to them.

I would think proof of that, at least the way I think, is you are saying after a valve adjustment and new CCT, a few thousand miles it sounded the same, and then a new chain and sounds a bit different but the same.

I guess while you are in there syncing you will look over your vacuum lines and such.

I hope you find it is truly "they all sound that way".

 
Have another biker listen to it and listen to another bike. The first time I thought I had cam chain problems, was when I would leave my driveway sometimes with a cold engine and head down the road. Never happened anywhere else. Realized after a while that it was the gravel in my driveway getting picked up by new tires and coming off.

 
Hi,

When I did mine awhile back, the new CCT went hyper and placed a LOT of tension on the cam chain.

It was like the cam chain flicked and caused the CCT to spring out more than it should.

It made a hell of a noise.

I was scared that it had slipped and took the cam covers off and checked everything.

All what was needed was to back off the CCT and re-apply the pressure once more.

Perfect ever since.

 
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... I tried it again this afternoon and it seemed to make just one "jump" noise before it warmed up to I then II bars and continued to idle along at 1100 nicely.

...

Jim
Could it be the engine misfiring? Some FJRs can exhibit a misfire during warm-up, usually described as a clunk. Sometimes happens once, sometimes several times during warm-up. Sounds mechanical, probably due to drive-train backlash (even idling in neutral).

Its onset can vary with almost any change in weather or bike's state of tune, stops as the bike warms up.

If that's the case, it's a total non-issue, it's due to the weak mixture the engine is running on and causes no problems whatsoever (except perhaps in the head of the owner :blink: ).

 
+1 with mcatrophy. The fuel injection on newer vehicles is set very lean, to the point of a lean misfire even when the vehicle is on "cold start". By running leaner it warms up the engine quicker, so the ECM can get into closed loop operation as fast as possible, which keeps the EPA happy. My 2009 has done the lean misfire since new when first started, it just gets more noticeable as the weather gets colder. I fire up the bike and then put on my coat, helmet, and gloves by then it's done the lean miss once or twice and we are ready to go. The sound does seem "mechanical" which is probably related to driveline lash. I hope this helps, let us know how it works out.

 
Not that it matters what I think, but I'm with mcatrophy on this one. I think the OP's hearing the typical "Kold Motor Klunk" of an FJR that's not up to temp yet.

Also agree with FJRay...my 03 motor does it, too. Occasional misfires until I see two bars on the temp gauge.

 
+1 on releasing and re-applying the CCT tension.

SeaFoam the motor. Ride it for at least two tanks of fuel. Then go back inside and check the valve clearances again.

I'm willing to bet you adjusted a/some exhaust valves that weren't all that tight to begin with. Now they have too much clearance and will clack like small hammers.

I've got two exhaust valves on the 07 that will make one helluva racket if they are set even .002" beyond minimum spec. Set them tight and the engine idles nice and quiet. Set them loose and it bangs like a Ford Pinto.

 
Hi,

When I did mine awhile back, the new CCT went hyper and placed a LOT of tension on the cam chain.

It was like the cam chain flicked and caused the CCT to spring out more than it should.

It made a hell of a noise.

I was scared that it had slipped and took the cam covers off and checked everything.

All what was needed was to back off the CCT and re-apply the pressure once more.

Perfect ever since.
This may not apply to the OP's situation, but the only way I would foresee a new CCT having "too much" tension on the chain would be if the tensioner was somehow released before you finished tightening the two mounting bolts. The spring tries to hold the spiral tensioner from retracting and I could see how this would result in excessive chain tension as it was bolted on.

You are supposed to have the tensioner fully retracted (and pinned) as you bolt it in place on the cylinder block and then only allow the tensioner to release (apply its tension) after it is bolted in place.

After the fact, once the tensioner is already in place, you could just retract it and then allow it to spring back into position (as you say you did) to correct it.

Note that, all of this should be done with the chain slipper guide being restrained from going completely slack, tie-wrapped or with a small socket jammed behind it, (but not "over tensioned")or you risk skipping a tooth on one or more sprockets of the slack chain.

 
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