Valve Checks vs. Adjustment Required Poll

[ionbeam]

To add on a tiny amount to what Fred Sez --

As the screw and lock nut rocker arm type valve train wears and starts to clatter the valve openings (lift) become smaller which improves low rpm port velocity and you will start to notice better low rpm power with an accompanying drop off in high rpm power. This is pretty much a fail-safe valve system, the valve lift gets smaller and performance will diminish until it becomes unacceptable, with no harm.

As shim/bucket valve trains wear valve lift increases resulting in lower port velocity at low rpm causing a drop in power and the higher lift increases breathing at high rpm allowing higher power. At least right up until the valves don't fully seat, then as Fred sez, the valve flute and/or the cylinder head valve seats start to silently burn. Check those valves as specified by Yamaha.

 

[mcatrophy]

To add on a tiny amount to what Fred Sez --
As the screw and lock nut rocker arm type valve train wears and starts to clatter the valve openings (lift) become smaller ....

That clatter is partially because the cam is been hit by the cam follower at a steeper angle than designed for, which (so I was told when I had a car with such an engine) could lead to pitting in the surface of the cam and/or the follower.

But it only took about ten minutes to check, another five to adjust.

 

[kieefjr]

I am curious.

How many replaced the cam chain tensioner and at what mileage?

Was it a pretty noticeable sound when it was replaced?

Correct me if I'm wrong but wouldn't the valves definitely need adjusting if the CCT was worn?

 

[RaYzerman19]

Valve adjustment is independent of the CCT. The CCT has a spring that simply keeps tension on the cam chain as the engine turns. A weak CCT can lead to the chain jumping a tooth or two, which then alters cam timing, which will likely lead to a valve hitting the top of a piston...... being the CCT was redesigned in late 2007, better stronger spring, it is advisable to change CCT's on prior FJR's. You will probably notice a loose chain, but it may be masked by other sounds..... and when it is loose, you don't know how loose.... personally, I'd change it without hesitation before it gets that far. Newest CCT has a green dot.

 

[ionbeam]

I am curious.
How many replaced the cam chain tensioner and at what mileage?

Was it a pretty noticeable sound when it was replaced?

Correct me if I'm wrong but wouldn't the valves definitely need adjusting if the CCT was worn?

Poll started in 2009 and covers all year FJRs

The cam chain only controls when the valves open (mechanical timing), not how much the valves open. The issue is when valve timing is off far enough that the valves are extended down into the combustion chamber (valves will be open) while the piston is coming up. When there is enough slack in the cam chain it allows the chain around the crank sprocket to jump teeth and then the valve/piston thingie happens.

There are three cam chain slippers, one vertical slipper down the front of the cylinder block, one vertical slipper with the CCT pressing on it which runs down the back side of the cylinder block and one horizontal slipper mounted in the valve cover to keep the cam chain from jumping teeth on the cam sprockets. When there is too little tension on the CCT slipper a 'chain snatch' loop can form at the crank sprocket allowing the crank sprocket to jump teeth. The crank sprocket is in a 2:1 ratio with the cam sprockets making any skipped teeth significant.

 

[Fred W]

CCT is a different poll over in the Technical Mechanical section

 

[ionbeam]

CCT is a different poll over in the Technical Mechanical section

^^^^^ Um, please check your work It looks like we both have the same link.

 

[Fred W]

Sorry for the duplication. I was thrown off by your "2009 to Present" link title (and did not click it).

That poll actually covers all model years.

 

[ionbeam]

Sorry for the duplication. I was thrown off by your "2009 to Present" link title (and did not click it). That poll actually covers all model years.

The poll was started in 2009 and covers all years. I Fredenated the link for ya, hopefully you wouldn't be afraid to click this link now.

 

[terryfarnham]

I did my own 1st. check. All good. I skipped over 2nd check till winter. I'll post once I know.

 

[wetwolf]

Bought the thing last year with 45k on it. 50k now. doin the valves. somebody has been in here before. the tbar was loose and only held on with 2 bolts. all valves are on the tite side of the spec. 4 of the intakes are to tite. borrowed a shim kit from a local shop and will get the valves done this weekend. new cct is on the way, it definitely had a cam chain noise going on, no paint on the cct. they sure pack that fucking engine in there tite.

1st time taking the thing apart. as usual, uncrewed a whole buncha screws that i prolly didnt need to. It will be buttoned up by next weekend. Have wynpro pair plates coming, got the mercury tubes ready to go.

Good thing I've got the bandit to ride

 

[mech 1 twa]

1st at 28k. 4-5 tight. Shimmed. Replaced that engine at 34k 4th gear issue. Installed Gen II engine with 22k

Checked valves before install all good but 1 loose exhaust left it alone, just slightly loose.

 

[wetwolf]

Alrighty then. All buttoned up, Did a 70 mile shakedown ride today and everything held together at 110 mph+ so I must have done something right. Now that I've been in there, it will be a cakewalk to get back in. Only had 1 bolt, 2 allen head, and one screw left over. I was expecting pthe bolt and the allen heads, but I'll be fucked if I know where that screw came from. It's a phillips head, 6mm about 10m long with a non captive washer. I'm thinking it is out of the upper/left side cowling area where I too WAY to many screws out.

Not gonna worry about it. I'll put it in a bag and next time I have it apart I will look around. Everything was pretty straight forward. Biggest gripe..............DO YOU REALLY EXPECT ANYONE TO REPLACE THE CCT AND NOT DROP BOLTS INTO THE BIG FUCKING HOLE ON THE INSIDE OF THE FRAME? Coincidentally located right where the CCT goes, for your convenience. After I had dropped a couple in there and couldn't get the last one out, I stuck a piece of painters tape over the hole. at least when I dropped a bolt then it either hit the floor or fell onto the engine.

Anyhoo, no more annoying cam chain clatter. Did the Barbarian jumper mod, but havn't yet tried to adjust anything so I don't know if that was successful or not. But then again, the bike ran and no magic smoke escaped from the ECU, so we shall see.

On a side note...... I saw my 1st robin of spring today. I was moving at a rather brisk pace which shall remain undisclosed when a robin flew across the road and made the mistake of trying to fly back the way he came right in front of me. I don't swerve for little creatures above a certain MPH. When i got back to town I could tell the poor little bugger didn't make it. I don't think I'm gonna wash the right side of the bike for a while just to let the other critters know that I won't slow down for them. heh heh heh

So, hey, put me down for 4 tight intake valves at 50,000 miles if anybody is keeping track.

Da Wolf

 

[jmdaniel]

Nice work, Fred. I came across this after getting quotes on the valve clearance check from local dealers, which ran right around 750 freakin' dollars!!!!!!!! I'm only at 28K on my '07A, (yeah, I know, and now I have a '16 F6B to not ride as well), and it was nice to see that those that did the check at the first service interval saw mainly nothing. The independent shop I talked to yesterday, (while also quoting me an astronomical price), advised it not be done, as it would be good money tossed. I think I'll use the money not spent towards a good lift table, and do my own check, somewhere down the line.

 

[Fred W]

Yeah $750 for a valve check should require them wearing a mask and pointing a weapon at you. That's highway robbery for sure. The job is not all that invasive unless / until you need to adjust the clearances. Even then it's not all that bad if you take your time.

Not thinking a lift table would be all that beneficial for this job as most of the work is done from the top. For a check, you don't even need to remove the faring lower panels. Just the left side inner dash panel to access the radiator filler.

Draining the coolantfrom the 10mm bolt in the waterpump, it may splash around off the lower faring somewhat. I use a disposable aluminum roasting pan to catch the coolant. No need to blow or flush it out, just refill with fresh coolant when you're done.

I do recommend removing the tank, even for just the check, especially on 2nd or 3rd Gens as the tank will not pivot up as high on those as it did on the old superior 1st Gens. So plan on having 1/2 a tank or less when you park it the night before. You'll want that anyway for the TBS afterwards, to let you run the bike with the tank tilted up.

The only parts you need are the two o-rings for the coolant pipe, a set of spark plugs (you'll want to remove them to make bumping the engine over with the back wheel easier), the replacement coolant, and some O2 sensor safe sealant for the valve cover gasket. Only put the sealant on the side of the gasket that goes to the cover. Then the gasket will last the lifetime of the bike.

Look around and you'll find many good accounts of what's involved. It will be a long day of wrenching the first time you do it, but is only about 4 hours start to finish after you've done it a couple of times.

 

[jmdaniel]

Thanks again, Fred, for all the tips. You're one of the fellas that really add a lot to this community.

It seems that all the dealers in the area, and the independent shops I have talked to, want the same amount for that valve check, so I'll definitely be doing it myself. Austin has become a very expensive place to live in the last ten years, relatively speaking, and that shows up in the shop rates.

 

[rbentnail]

In addition to Fred's thoughts I always take the windshield off. It's not necessary to do so but after the 3rd or 4th or 5th time you bump into it you'll see why.

 

[RossKean]

So what do you do after five valve checks?? The poll runs out of options.

I just did my 5th check after 173,000 miles or so. It was close to 50,000 miles since my last check. On the previous check, I made a number of adjustments for the first time. This time, one intake on #4 was just below spec and the other on #4 was right at minimum spec. I sanded these shims to bring them back to where they needed to be. I also confirmed (to no surprise) that previously sanded shims wear the same (i.e. not at all) compared to factory shims. I was a little surprised to see the #4 shims off a bit while the others were all good. I have never had to adjust any exhaust valves.

 

[Bill Lumberg]

Valve service isn't nearly that expensive at the shop in use. I'm due for my second check/adjust on my 2014. Trying to find time to get it done.

 

[Wistrick]

Checked mine on my 07 FJR with 45k and all where in spec...some on the low side of spec, but in spec is in spec...Did change out the stock CCT though