Releasing Cam chain tensioner

[The good show]

The manual mentions a hex tool used to compress/release the cam chain tensioner but, for the life of me, I can't find one online. I've tried various hex sockets sizes and none seem to fit. 

 

Has anyone had any experience with this or know an alternative way to adjust the tensioner?

 

 

[DewMan]

Have you tried half sizes like 4.5mm and 5.5mm? they're not as common in a set but used enough that they could be the size you need.

 

If it's actually a long hex shaft You could use an Allen wrench of the correct size I would think?

 

If that's the case I would find a Hex wrench of the correct size and cut it to length so you could use a socket on the protruding end.

There are Hex sockets that have longer shafts that could possibly work as well.

 

That being said I've not had to work on my timing chain yet so this is all just guess work.

 

Good luck finding a solution. Let us know how it goes.

Edited July 22, 2018 by DewMan

[rick]

This is from the FZ09 forum, but page down to post #8  https://www.fz09.org/forum/6-fz-09-general-discussion/8274-cam-chain-rattling-like-maraca.html

 

Yeah, it looks like a hex wrench.

 

On page 5-22 of the manual, there's more description, but it's just as confusing. Looks like the 1st wrench to hold the tensioner is generic, but maybe the 2nd as DewMan suggested is an odd size - maybe smaller and fits inside the 1st hex. 

 

That part number, btw sorta partially pops up in the cam diagrams - https://www.yamahapartshouse.com/oemparts/a/yam/58a22b9e87a866120cd9f126/camshaft-chain 

 

What's really not clear to me is that there's a spring, but it's adjusted manually up reinstall. 

 

In my universe, if I can't find one to fit, I'll sacrifice a key that's one size big and carefully grind it down until it does. 

Edited July 22, 2018 by rick

[DewMan]

4 hours ago, rick said:

In my universe, if I can't find one to fit, I'll sacrifice a key that's one size big and carefully grind it down until it does. 

Been there, Done that, on more than just Hex keys. I've used a grinder on sockets, screwdrivers, wrenches, pliers etc if that's what it took to get the job done. Saved lots of $$ on "specialty" tools this way over the years.

[callmepro]

If it is a standard size then it looks like it's a 3.5 (assuming it's metric).

 

 

Edited July 22, 2018 by callmepro

[rick]

You can very much assume it's metric - whatever the factory spec was to force us to the dealer. 

 

But if it's really 3.5mm, that translates to 2.2/16". Try a 1/8" hex key. It might fit with just wee bit of slop. 

[MT27]

At what mileage do the acct fail?

[rick]

The Fz09 tensioner had issues Early on and has been redesigned. 

 

. That's not been the case with the 07. They look similar in design - at least externally, but there really hasn't been much conversation about the FZ7's tensioner causing/allowing cam chain rattle. 

 

If it's not making noises, leave it be. It's not gonna all of a sudden "fail"

[The good show]

ok, so it ended up being a 3mm hex. My cct hasn't actually failed - I just need to release tension on the cam chain so I can easily remove it. thanks for all the tips!

[rick]

So what the heck is the inference between the #1 and #2 wrenches in the manual.

 

Are you replacing valve shims? 

[The good show]

2 minutes ago, rick said:

So what the heck is the inference between the #1 and #2 wrenches in the manual.

 

Are you replacing valve shims? 

 

honestly, it's baffling. There's a small, threaded bolt that you remove to get to the adjuster but that's it. unless hex 1 comes installed in a brand new cct?

[rick]

I believe the outer bolt is just a cap/cover over the hole. 

 

I'm guessing that turning the internal hex wrench holds the tensioner back, taking pressure off of the chain as you unbolt the thing from the case. 

 

I've not been impressed by the service manual. Details like this procedure could easily be way better.  Engineers sometimes do not make the best technical writers. And sometimes technical writers need more practical experience. I once had an electrical engineering student work part time in my lab. He knew lots of theory, but had never actually seen the inside of an electrical motor, before I pulled one apart to replace the carbon brushes. 

 

I guess we get what we pay for - the manual was pretty cheap, and sure way better than nothing. 

[norcal616]

Probably a JIS sized hex key will fit... Japan loves JIS sized bolts,nuts...

[noodles]

So I read this whole thread a few times and all I've gathered is that the hex key size is 3mm. How do I actually release the tension on the cam chain while it is still bolted to the bike if I have a 3mm key? The service manual gives no details, just to use the tool. 

[norcal616]

According to my FJ-09 manual it says wind it CCW till it stops to remove the CCT, you must also unbolt the two housing bolts and hold the CCT in place via hand prior to unwinding the CCT...if it comes out "smoothly" it's good- if not replace it

Replace by turning CW till it hits the chain guide, then add 1/4 turn and lock it... 

Edit: it's not ment to be manual adjusted as its self adjusting as the guides/chain worn down... There has been 1 case of an FJ-09 owner destroying his engine due to his "tinkering" of the OEM CCT(not that he will admit it) years ago...

[noodles]

8 hours ago, norcal616 said:

According to my FJ-09 manual it says wind it CCW till it stops to remove the CCT, you must also unbolt the two housing bolts and hold the CCT in place via hand prior to unwinding the CCT...if it comes out "smoothly" it's good- if not replace it

Replace by turning CW till it hits the chain guide, then add 1/4 turn and lock it...

Yeah I read the FZ09 threads and didn't get any clarity. I can't turn my CCT in either direction but I do have the right sized tool. I shimmed my valves and I'm trying to put it all back together, but I think the CCT is too tight. I can't even move the crank, but the valves are in time. So it's either the cam caps or the CCT and my money is on the CCT until I can remove it and see if I can turn the crank without tension on the chain. 

 

EDIT: when I had the CCT off the bike in my hand I played with it to figure out how it worked. I could wind it back turning CCW and leaving the key in. The moment I removed the key it would snap back out. So I figured to remove it you wind CCW until it stops, unbolt from block, then to replace you tighten it up to fit it in, replace the bolts, then remove key to snap the spring back outwards since it is self-adjusting... but now that I've done that I can't wind it CCW again to get the damn thing back off.

Edited July 5, 2019 by noodles

[cptsolo]

Can the OEM tensioner be adjusted/reset while on the bike?  

Also, do I need the special key or can a normal hex key do the job?

My chain tension is now too tight after I messed with the OEM tensioner (half removed it) while on the bike.  After half-removing the tensioner's two mounting bolts, I aborted and tightened them back in.  But now the chain tension is way too much, the starter struggles and the chain is whining.  

[noodles]

4 hours ago, cptsolo said:

Can the OEM tensioner be adjusted/reset while on the bike?  

Also, do I need the special key or can a normal hex key do the job?

My chain tension is now too tight after I messed with the OEM tensioner (half removed it) while on the bike.  After half-removing the tensioner's two mounting bolts, I aborted and tightened them back in.  But now the chain tension is way too much, the starter struggles and the chain is whining.  

1. It is self-adjusting. No, remove it and replace it

2. Cut a hex key down so that it can fit underneath the second hex key you need to tighten/remove the bolts

3. Remove it and replace it, follow my thread here, post #2 "Adjustment", item #4:

On 8/7/2019 at 1:56 PM, noodles said:

Remove the cam chain tensioner next. Begin by removing the cover bolt on the cam chain tensioner (1). Then insert a 3mm hex key and begin twisting counter clockwise until it can't be turned anymore (2). This will retract the cam chain tensioner back into itself so that it relieves pressure applied to the cam chain. The hex key stays in the tensioner during this process. If it is removed, the tensioner will immediately SNAP back out, so keep the hex key in place! You might need a trimmed or short key to accomplish this (see the thread linked above), because the airbox will be in your way as you try to unfasten the 2 hex bolts that hold the tensioner onto the block, so you have to use a hex key instead of a ratchet + socket. But then the arm of the hex key can't reach over the inserted 3mm hex key unless the 3mm is trimmed down. Also, even when wound back completely, the tensioner will still be in contact with the chain, pressing back on the tensioner. That means as you remove the bolts, they may be under some tension. Take your time and don't force anything. Once you have the tensioner off the block, rest it gently on something soft and use a careful touch with the gasket if you plan on reusing it.

 

 

[cptsolo]

Cheers Noodles.  

Done, resolved with the current tensioner.  Once out I checked it and was working fine.  The mechanism only becomes clear once it's in your hand.  I reinstalled and 'reset' it which seems to have done the trick, also fixed the long standing cam chain rattle since new.  Hopefully it stays good.

Thanks for the help.

[Soldier84r1]

Bloody hell first rule is never believe anyone who just talks on a forum. If your cam tensioner is plus 10k miles highly and I mean highly recommend replacing it ASAP! Lmfao some dude in here talking about it won’t just suddenly fail if it’s been working and they don’t have issues like the fz09. No sir they all fail and very suddenly. Can you go 30k sure sometimes but the reality is when they fail it’s bad news bear and this one thing for 100 bucks and half an hour you don’t chance. Ride one folks replace those CCTS! 

[Voz Spoz]

I am completely baffled over the MT07 CCT. I can wind it back CCW with a 3mm, no problem. My issue is the install, are we meant to bolt it back in then simply remove the 3mm Allen key or are we meant to turn the 3mm Allen key clockwise until we feel it pressing on the cam chain guide then turn 1/4 CW and remove the Allen key?

[klx678]

On 12/3/2020 at 10:35 PM, Soldier84r1 said:

Bloody hell first rule is never believe anyone who just talks on a forum. If your cam tensioner is plus 10k miles highly and I mean highly recommend replacing it ASAP! Lmfao some dude in here talking about it won’t just suddenly fail if it’s been working and they don’t have issues like the fz09. No sir they all fail and very suddenly. Can you go 30k sure sometimes but the reality is when they fail it’s bad news bear and this one thing for 100 bucks and half an hour you don’t chance. Ride one folks replace those CCTS! 

Depending on tensioner design they may or may not catastrophically fail.   I make tensioners for a variety of motorcycles, but predominantly KLX250, CRF250, WR250, and VTR1000 Superhawk/Firestorm.   I have the bodies for the 07/700 and 09/900 engines but not had any call for them at this point.

The only one that can catastrophically fail from what I've learned is the VTR1000 and it is the front one that fails.  The layout of the front cylinder makes it difficult for oil to get to the mechanism, but the corrosive mist that can happen when the engine is not fully warmed and the mist evaporated off, will get to the mechanism.  This can cause corrosion and a catastrophic failure on the front cylinder, destroying valves, heads, pistons and even cylinders.

Most all the rest have progressive failure, especially the ones that use a ratchet style mechanism.  They start clicking, some at specific upper rpm, eventually getting louder and over a wider range.   When they rattle it is time to get ready to replace the tensioner.   You have some time unless it is really loud.

How do you learn if your tensioner is the issue?  You listen.  If the noise is loudest on the cam drive side it is the tensioner allowing chain slap and snapping back and forth.  That is the failure, the plunger being pushed in and snapping back out.   For a more exact listening method, use a mechanic's stethoscope (can be had under $10) or a long handle screwdriver putting your ear against the handle.  Place the tip in different places on the engine, when you get near the point of the source of the noise the sound will be loudest.  I can pick out two valves that are .001" out of spec on my Zephyr with this method.  Again, loudest at the cam chain tensioner.

If you have the ratchet type where you can see the ratchet teeth on the plunger the teeth may look fine, but a close look reveals one tooth tip really worn and a pattern of wear from the push back and clicking back out.  It's like worn shifter dogs allowing the transmission to pop out of gear, the dogs, at a glance look okay, but the tip is rounded and the engaging surface worn.

Regardless, it is time to replace the tensioner.   OEM is expensive, manual is low priced.  Manual is easy to live with for anyone who can follow directions.   The name "tensioner" is improper for the manual unit, it is a cam chain adjuster.  Chains are not designed to run under tension.  Optimum adjustment is zero chain slack, being a bit loose is better than too tight.   They do not require constant attention.  I've run 12,000 miles on my 550 with no adjustment, only a few adjustments on my 650 starting with new chains over 50,000 miles.   You listen.  If there is slight ticking you adjust, otherwise no problem.   When chains are seated in they require extremely infrequent attention.  No ticking no adjustment.   I have full instructions with the kits and on line at my web site.

I'm not here to try to drum up business or anything, just to set things clear.   I don't know if I ever mentioned making the parts in this forum.  I'm here because I have an XSR700 and this forum was part of what assured me I was looking at the right bike at the time I was looking.  Now if some ask about the part I will deal with that then.  

[mossrider]

11 hours ago, Voz Spoz said:

I am completely baffled over the MT07 CCT. I can wind it back CCW with a 3mm, no problem. My issue is the install, are we meant to bolt it back in then simply remove the 3mm Allen key or are we meant to turn the 3mm Allen key clockwise until we feel it pressing on the cam chain guide then turn 1/4 CW and remove the Allen key?

It automatically sets itself when you pull the hex key.

[RoscoeF]

On 9/9/2019 at 5:25 PM, cptsolo said:

Cheers Noodles.  

Done, resolved with the current tensioner.  Once out I checked it and was working fine.  The mechanism only becomes clear once it's in your hand.  I reinstalled and 'reset' it which seems to have done the trick, also fixed the long standing cam chain rattle since new.  Hopefully it stays good.

Thanks for the help.

Hi ctpsolo, 

I think I've done a similar thing to you in that my chain is now too tight and the starter is struggling to start the bike.

I was wondering if you simply removed the CCT and then reset it and then reinstalled it on your bike OR did you remove any engine covers in order to be able to maintain tension on the cam chain when the CCT was out of the bike?

 

Thanks in advance

[cptsolo]

10 minutes ago, RoscoeF said:

Hi ctpsolo, 

I think I've done a similar thing to you in that my chain is now too tight and the starter is struggling to start the bike.

I was wondering if you simply removed the CCT and then reset it and then reinstalled it on your bike OR did you remove any engine covers in order to be able to maintain tension on the cam chain when the CCT was out of the bike?

 

Thanks in advance

Hi Roscoe, 

I followed the steps in the service manual before removing the tensioner.  From memory it went something like:

1) Remove spark plugs

2) Turn the crank to the top dead centre position marker.  This will ensure the chain will not jump a position once the tensioner is out.

3) Remove the tensioner and check that it is serviceable by following the process in the manual.  Tensioner was good, so I reinstalled it after resetting the tension.  Problem solved.

Be aware of the clear advice above that the tensioner should be replaced.  Looking back I probably should have done this also, but nearly 20,000km since I did this, it is still going fine (touch wood).  I should do this now though, since you have reminded me.

Good luck and it's not a major job.  The biggest hassle is getting everything off to get to the plugs of course.

Cheers