Who will be changing there chain tensioner to the 14' during valve adjustment ?

[Karson]

You need to remove the clutch cover to access the cam chain tensioner?

You'll have a lot better luck searching the SM using "timing chain tensioner" ::008:: Chapter 5 around page 19 in my service manual.

 

[twinrider]

Didn't you say you just looked through the service manual? It's all in there.

You have to remove the clutch cover to smack the cam chain with a screw driver to release the tensioner after you install it.

ac

I am looking. On 5-16 I see where it says to remove the CCT but it looks nowhere near the clutch. I admit I am a wrenching retard... :

 

[cosmic]

Welcome to the club

 

[avc8130]

I am looking. On 5-16 I see where it says to remove the CCT but it looks nowhere near the clutch. I admit I am a wrenching retard... :

Yup...

Now keep reading and follow all the way through re-installation.

ac

 

[Don in Lodi]

What's the tie-in between changing the cam chain tensioner and the valve clearance check? My Yamaha dealer said the labor involved is completely unrelated.

Sent from my PC36100 using Tapatalk 2

If the cams need to be lifted to actually do an adjustment during the valve clearance check the tensioner is removed so the chain is not under tension when pulling things apart. Simple swap out at that point. It should be included in the labor rate for the adjustment, probably not included for just a check.

 

[BWC]

All this talk of cam chain tensioners I decided to take the 23P tensioner I removed from my 2012 and take it apart a bit further. Was replaced with the 2BS part for the 2014

With the internal parts removed

An allen head screw that covers what looks to be a check valve to maintain oil pressure within the CCT body. And a small phillips head screw that is used to cap off a drilled oil passage.

Looks like an oil check valve which appears to be pressed in

Inside with a shoulder that the hollow screw portion of the assembly sits against which feeds oil into the plunger/piston assembly

And what looks to be some wear marks on the inside of the tensioner body

And reset ready for reinstallation

So my question is what exactly is there to fail on this part? Just the wear we see? The plunger/piston is forced out by the internal springs, screw assembly is one way out against the chain,and oil pressure is also used.
The only thing that was apparent between the old and new CCT when resetting them was the old one was fairly easy to push/thread back in and the new one was very difficult to wind in when resetting it. As you had to have just enough, but not to much pressure on the piston to get it to thread back in. It just felt like the threaded tolerances were much higher.
Ideas?

 

[Koinz]

Well, springs do weaken as they go through multiple heat cycles and the check valve could also leak emptying the tensioner of oil when at rest.

When I had mine out for the valve adjustment, the oil was very dirty as if to imply that there's not much circulation through the tensioner. It basically fills up with oil and a small amount might leak out, but for the most part it's in there to stay gumming up the works.

 

[scott123007]

In my opinion, that's a BS excuse. EVERY chain driven cam motor in any motorcycle, regardless of brand, works like this.

Clearly they are pretty unfamiliar with motorcycles in general...I'd be wary.

ac

AC, that's FAR from correct. MANY chain driven overhead cam bikes have shim OVER bucket or rocker arms. Cam removal is not necessary for valve adjustment. I am well aware this is not the case in this instance, and that most modern day engines are shim under bucket, but I'm just setting the record straight.

 

[scott123007]

Well, springs do weaken as they go through multiple heat cycles and the check valve could also leak emptying the tensioner of oil when at rest.

When I had mine out for the valve adjustment, the oil was very dirty as if to imply that there's not much circulation through the tensioner. It basically fills up with oil and a small amount might leak out, but for the most part it's in there to stay gumming up the works.

Springs are not the problem, but a leaky check valve, could well be.

 

[avc8130]

AC, that's FAR from correct. MANY chain driven overhead cam bikes have shim OVER bucket or rocker arms. Cam removal is not necessary for valve adjustment. I am well aware this is not he case in this instance, and that most modern day engines are shim under bucket, but...

Fair enough, but even shim OVER bucket needs the cam out. Rocker arms are about the only setup that doesn't and those are becoming fewer and further between.

Either way. ANY Yamaha dealer that does service should be familiar with shim under bucket by now.

ac

 

[True Grip]

Dirt Tricks makes an interesting tensioner for the KTMs. It's hydraulic but ratchets at stops then holds like a manual tensioner. It never releases until you remove it.

 

[twinrider]

Yup...

Now keep reading and follow all the way through re-installation.

ac

OK, I see where it has to be removed and reinstalled when removing/reinstalling the cams. Still not getting the clutch cover relation to the tensioner. Got a reference to a service manual page with a pic? I just want to know what I'm talking about when I visit the dealer.

 

[scott123007]

Fair enough, but even shim OVER bucket needs the cam out. Rocker arms are about the only setup that doesn't and those are becoming fewer and further between.

Either way. ANY Yamaha dealer that does service should be familiar with shim under bucket by now.

ac

Christ, you're sounding more like Dallara every day
You don't have to ad lib about what a Yamaha dealer should be familiar with because that had nothing to do with this. I wasn't defending them for not knowing what an S-10 had for a valve train, I was just correcting your blanket statement.
And NO, cams do not have to be removed for shim over bucket.

 

[avc8130]

overnight bleed down should not be a problem, it should pump up on restart, however i guess a continuously leaking check valve that bleeds a quantity close to the feed volume could be a problem ?

It does pump up on restart. That is why the clatter stops once oil pressure is built up.

ac

 

[avc8130]

OK, I see where it has to be removed and reinstalled when removing/reinstalling the cams. Still not getting the clutch cover relation to the tensioner. Got a reference to a service manual page with a pic? I just want to know what I'm talking about when I visit the dealer.

5-22

 

[twinrider]

5-22

Cheers. ::003::

 

[avc8130]

Christ, you're sounding more like Dallara every day
You don't have to ad lib about what a Yamaha dealer should be familiar with because that had nothing to do with this. I wasn't defending them for not knowing what an S-10 had for a valve train, I was just correcting your blanket statement.
And NO, cams do not have to be removed for shim over bucket.

Hmm...I see this. Too bad more manufacturers don't use shim over bucket. Neat.

I'm pretty sure Twinrider made a claim about what his dealer told him. His dealer appeared to be trying to poach him for extra cash claiming changing the tensioner was "completely unrelated" to a valve check/adjust. So that did have something to do with this.

I do stand corrected. Shim over bucket looks pretty neat. I've never dealt with that personally as every motorcycle motor I have worked on was either shim under bucket, rocker arm, or a combination of both on the same motor (Honda Unicam).

Does Yamaha actually use shim over bucket?

ac

 

[avc8130]

Cheers. ::003::

Yeah, Yamaha really missed the ball. If you follow the valve adjustment procedure in the periodic adjustments section it just tells you reinstall everything as the reverse of the disassembly. There is just a "Tip" that says to "Refer to CAMSHAFTS 5-11". Pretty easy to overlook. That would almost instantly result in an exploded motor. You have to dig into the camshaft section to find the procedure to release the tensioner.

ac

 

[scott123007]

Does Yamaha actually use shim over bucket?

ac

Back in the day they might have, not really sure. Kawasaki and Suzuki did for sure. It's older technology, heavier than SUB and more prone to spit a shim at high RPM's. With the stratospheric RPM's of a lot of the current high performance bikes, they would not be reliable. What's disappointing, is with the low rev ceiling of the Big Blue Pig, it could have had shim over bucket or even hydraulic valves without reliability issues.

One interesting phenomenon is that with shim over bucket, by far, the majority of valve adjustments required larger shims, because valve clearances way more often than not, grew instead of shrunk.

 

[Don in Lodi]

The Royal Star was shim over. You had to buy this special tool we called the 'snail'. It would engage on flats cast into the cam, you would then turn the crank and the snail would engage the buckets, compress the valve springs away from the cam face, then with a strong magnet, need to break the oil tension, slip the shim out, slide the new, previously measured shim into place. Wasn't really hard once you had all the stuff lined up.
Yep, that was my understanding as well, low rpm = shim over... high rpm = shim under. Don't know where the break point is for rpm. They may have gone shim under for everything by now.