Valve adjustment no good?

[The_big_dill]

Hi all,

Just finished a valve adjustment and the bike seems to idle a lot better, have better response time and rev up and down a lot smoother than before.

However, when i pass something like 4k rpm it sounds as if something is loose... (hard to describe noise), as if i made the clearances too big and now the cam is hitting the tappet very loosely.

I did set the clearances to the outer limit of acceptable range.

What do you guys think i should do? Open it up again and set to tighter tolerances?

[Motofool]

Did you verify the timing of the camshafts?

Did you service the CCT while working on the valves?

Normally the noise comes more from a loose cam chain than from valves with max clearance.

http://faq.ninja250.org/wiki/Cam_cha...sioner_removal

[The_big_dill]

Originally Posted by Motofool

Did you verify the timing of the camshafts?

Did you service the CCT while working on the valves?

Normally the noise comes more from a loose cam chain than from valves with max clearance.

http://faq.ninja250.org/wiki/Cam_cha...sioner_removal

How would i verify timing? I did not check the cam chain tension.

I read the line on the link you sent me, pretty much saying what i am.

So how can i be sure that its the tensioner?

[Motofool]

Well, I am not sure that that is the source of the noise, but is not rare.

Check this similar thread:

http://www.ninjette.org/forums/showt...t=CCT+motofool

There is no way to "see" the tension of the chain after the valve cover has been closed.

You can find directions in the Top End section of your repair manual.

This is not in the manual, but it is critical:
http://n4mwd.blogspot.com/2013/06/ov...ts-during.html

[The_big_dill]

I will be opening the valve cover again as i should torque the locknut properly.

I heard your engine could go if you over torque those, why would that happen?

[Motofool]

Check the second link, where the reason for the proper torque and how the tabs can break is explained.

Avoid rotating the engine clockwise (looking from the left (generator) side or the cam chain could jump one tooth of the sprockets.

[The_big_dill]

Originally Posted by Motofool

Check the second link, where the reason for the proper torque and how the tabs can break is explained.

Avoid rotating the engine clockwise (looking from the left (generator) side or the cam chain could jump one tooth of the sprockets.

Sorry i am getting carried away as it is late, didn't see the second link.

Looks like im busing to work tomorrow, gonna get that thing apart and torque it properly.

I have a feeling that the tensioner is a problem though, i will give it a good cleaning as well.

Cheers,

Thanks for the help.

[Motofool]

You are welcome

Best !!!

[The_big_dill]

Originally Posted by Motofool

You are welcome

Best !!!

Here is an update.

I re-adjusted the valves last night and torqued the locknuts to 14.5 ft-lbs.

I also took out the tensioner, cleaned, regreased and reassembled back in place. Problem was that the screw that holds the mechanism from springing into place got striped, so i had to hold it in place while a friend tightened the 2 bolts down.

One thing that did worry me is the chain slack that i could see between the two camshaft gears (when you take the upper camchain cover/guide). How much slack should there be?

I measured 10 links of the cam chain to be around 60cm.

[Motofool]

Originally Posted by The_big_dill

............One thing that did worry me is the chain slack that i could see between the two camshaft gears (when you take the upper camchain cover/guide). How much slack should there be?

I measured 10 links of the cam chain to be around 60cm.

With the spring of the tensioner putting pressure on the rubber guide and you rotating the engine counter-clockwise only, there should be no visible slack in the cam chain (See point #3 of the second schematic for cam timing).

The value of that measurement is impossible.
Ten links (under some tension) should measure 64,45 mm (2.54") max.
The measurement should be repeated in several lengths of the chain (what requires rotation of the crankshaft).

[The_big_dill]

Originally Posted by Motofool

With the spring of the tensioner putting pressure on the rubber guide and you rotating the engine counter-clockwise only, there should be no visible slack in the cam chain.

The value of that measurement is impossible.

Looking in the 86-87 manual, i can see that even they have some chain slack. But i have a slight bit more. I have enough to be visible.

Could the CCT have worn out? i do not know the history of the bike so i am assuming its original CCT. Do these things tend to wear down so much that they don't hold the correct tension anymore?

Otherwise, could the cam chain guides wear out?

And regarding my measurement, i meant 60mm or 6cm. :P

[Motofool]

Yes and yes.
Either one is bad.
Recheck my edited previous post please.

[The_big_dill]

Originally Posted by Motofool

Yes and yes.
Either one is bad.
Recheck my edited previous post please.

Thank you

[tc.young]

how many miles are on the bike.

i always set mine a bit loose and they are a bit loud but ear plugs get rid of that. nothing went wrong on my almost 2000 mile trip to deals gap.

[The_big_dill]

Originally Posted by tc.young

how many miles are on the bike.

i always set mine a bit loose and they are a bit loud but ear plugs get rid of that. nothing went wrong on my almost 2000 mile trip to deals gap.

43,000 km.

I don't ignore noises... or try not to, they usually mean something bad. And in my case, i have a feeling its the chain not getting enough tension.

Also, things like this don't just break instantly, its a consistent degrade.

[The_big_dill]

Does not seem like anyone is selling the entire assembly of the CCT for the 1987 Ninja 250. It has different part numbers than the parts diagram you gave me, but looks identical. Furthermore, 12048 on the diagram you gave me does not exist on the '87-90'+ diagram.

I asked for separate parts and i can get the lower spring (fatter and shorter one) but the top one is discontinued.

Do you guys think i can get the CCT from the late F-series and stick it in my bike?

[quarterliter]

Mechanical CCT. Its the way to go.

[The_big_dill]

Originally Posted by quarterliter

Mechanical CCT. Its the way to go.

Sounds aftermarket, where can i get one?

[Motofool]

Originally Posted by The_big_dill

........Do you guys think i can get the CCT from the late F-series and stick it in my bike?

I don't know that for sure, but it should be very close.

As explained in one of the previous links, that is a ratcheting mechanism that put pressure on the chain to keep it tensioned, but much more importantly, it avoids any return to a previous position.
There is a bearing jamming the plunge against a conical surface to achieve that.
I have seen bearings going bad due to lack of lubrication, squaring off the little balls.
That prevents the proper jamming of the plunge.

The mechanism has a limit, and cannot tension a chain that has stretched beyond specs.

Have you checked the guides and if the slack of the chain persists?

[The_big_dill]

Originally Posted by Motofool

I don't know that for sure, but it should be very close.

As explained in one of the previous links, that is a ratcheting mechanism that put pressure on the chain to keep it tensioned, but much more importantly, it avoids any return to a previous position.
There is a bearing jamming the plunge against a conical surface to achieve that.
I have seen bearings going bad due to lack of lubrication, squaring off the little balls.
That prevents the proper jamming of the plunge.

The mechanism has a limit, and cannot tension a chain that has stretched beyond specs.

Have you checked the guides and if the slack of the chain persists?

The bearing inside the tensioner is in good shape, i used some bearing grease on it.

Wouldn't i need to pull off the head to check the guide wear? or at least the cam shafts?

[Motofool]

Then, it may be working properly.

Yes, the valve cover and maybe the tank.
You can use a flashlight down the well of the cam chain to inspect the guides for evident damage.

If the chain keeps the tension all around while you rotate the engine by hand and if the cams are in proper timing, then everything is working properly regarding the chain and tensioner.

[The_big_dill]

Originally Posted by Motofool

Then, it may be working properly.

Yes, the valve cover and maybe the tank.
You can use a flashlight down the well of the cam chain to inspect the guides for evident damage.

If the chain keeps the tension all around while you rotate the engine by hand and if the cams are in proper timing, then everything is working properly regarding the chain and tensioner.

I meant to say the cylinder head needs to come off if i wanted to inspect or replace them.

When you say tension all around, you mean the slack doesn't vary as the engine turns, or?

[Motofool]

No, the head does not need to come out to replace the guides, in case they are worn.

Yes, that is what I meant.
There are some angles at which the cams and valve's springs push the chain to slack a little between both cam sprockets, but that slack should be noticeable but be very little.

[The_big_dill]

So as it turns out, i cannot get the entire assembly, in fact, the parts diagram for the E and early F series didn't include the tensioner assemble as an assembly part number (12048).

I called locally and one of the springs is discontinued. If i were to replace worn out parts in the tensioner, what would i be looking to replace? Which spring does the tensioning work on the cam?

[Motofool]

92081 is the spring that pushes the chain.
The other spring is just to keep the bearing as high as possible so it catches any kickback of the plunge.

[The_big_dill]

Originally Posted by Motofool

92081 is the spring that pushes the chain.
The other spring is just to keep the bearing as high as possible so it catches any kickback of the plunge.

Thank you

Anything else i should replace in this assembly?

[Motofool]

You are welcome

Just check that the surface of the plunge on which the bearing slides is free of dents or pitting.
You want the little balls to roll free over that surface.

You can use a file to fix any minor imperfection.

Best luck !!!

[n4mwd]

Originally Posted by The_big_dill

I re-adjusted the valves last night and torqued the locknuts to 14.5 ft-lbs.

This is critical. See my blog below for why.

I also took out the tensioner, cleaned, regreased and reassembled back in place. Problem was that the screw that holds the mechanism from springing into place got striped, so i had to hold it in place while a friend tightened the 2 bolts down.

You should never do that. You may have damaged your engine case. If your friend used the bolts on the CCT to pull it down, he could have broken the CCT hinge underneath. If your hinge is broken, no amount of fiddling will tighten your cam. If you run it that way (with a timing chain that is too slack), you run a high risk of destroying the engine.

Hopefully you didn't break anything, but if you did, it usually means buying a new case or welding the old one. If your cam chain wont tighten, then its time to pull the clutch cover off and inspect the internal CCT mechanism.

Another way to test (not inspect) the CCT mechanism underneath is to take off the valve cover and the timing chain guard over the two cams. Then poke a socket extension down the CCT hole and see if you can feel any effect on the chain with your finger. You should be able to vary the slack from very loose to very tight. If you can't, the CCT hinge is probably broken and you'll need to remove the clutch cover to inspect.

Another test for a broken CCT hinge is to use a socket extension to press down in the hole (moderate force) and see what happens when someone rotates the crank by hand (not the starter). This test will confirm or deny that the CCT hinge is bent/broken and jamming the clutch basket gear.

If the philips screw on the CCT housing is stripped, I suggest buying an allen head bolt at the hardware store to replace it.

FYI, here is a video showing how the CCT mechanism works underneath:

Link to original page on YouTube.

[The_big_dill]

Originally Posted by n4mwd

This is critical. See my blog below for why.



You should never do that. You may have damaged your engine case. If your friend used the bolts on the CCT to pull it down, he could have broken the CCT hinge underneath. If your hinge is broken, no amount of fiddling will tighten your cam. If you run it that way (with a timing chain that is too slack), you run a high risk of destroying the engine.

Hopefully you didn't break anything, but if you did, it usually means buying a new case or welding the old one. If your cam chain wont tighten, then its time to pull the clutch cover off and inspect the internal CCT mechanism.

Another way to test (not inspect) the CCT mechanism underneath is to take off the valve cover and the timing chain guard over the two cams. Then poke a socket extension down the CCT hole and see if you can feel any effect on the chain with your finger. You should be able to vary the slack from very loose to very tight. If you can't, the CCT hinge is probably broken and you'll need to remove the clutch cover to inspect.

Another test for a broken CCT hinge is to use a socket extension to press down in the hole (moderate force) and see what happens when someone rotates the crank by hand (not the starter). This test will confirm or deny that the CCT hinge is bent/broken and jamming the clutch basket gear.

If the philips screw on the CCT housing is stripped, I suggest buying an allen head bolt at the hardware store to replace it.

Thanks for the details.

The screw that holds the CCT assemble in place while installing the assembly does have a stripped head. What is the measurements of the bolt that i should get?

What i meant by my method of tightening that CCT is that i held down the CCT assembly in its position (springs compressed properly) while a friend took the two bolts and tightened them carefully. We were not using the bolts/threads to pull down the springs.

They discontinued a few of the parts for the CCT for my bike. It is a different part number than the ones motofool gave me in his diagram. I ordered the longer spring and a new O-ring.

Yesterday i rode with the valves adjusted and the CCT regreased and it did seem to run better, and the sound is not as high pitched anymore, but it definitely does not sound good... And after about 80km of driving, it sounds even worse, now i am getting concerned.

[The_big_dill]

Here is a link where i show you how loose my cam chain is:

https://skydrive.live.com/redir?resi...MsQt2GVcDJ4lc4

[n4mwd]

Originally Posted by The_big_dill

What is the measurements of the bolt that i should get?

M5-0.8 x 8mm long.


$9@Lowes, but your local hardware store may have a better deal. Ask for a 5mm-0.8 x 8mm Button-Head Allen-Drive Metric Socket Cap Screws. If they only have one that is 10mm long, you'll also need some washers for spacers.

When you replace it, just snug it in because it is only a cork once the plunger is released.

What i meant by my method of tightening that CCT is that i held down the CCT assembly in its position (springs compressed properly) while a friend took the two bolts and tightened them carefully. We were not using the bolts/threads to pull down the springs.

The round doughnut thing with ball bearings in it is a ratchet. You can't force that to the mating position without damaging something. Hopefully, its just the external CCT that got messed up. The springs are rarely the problem. Sometimes balls will fall out of the ratchet and it will need replacing.

Did you do the test with the socket extension like I described? This is to see if the internal CCT mechanism still works. If it does, then probably all you need is a new CCT housing which can be bought on ebay.

If the internal CCT is bad, then you need to pull the clutch cover and see what is going on. Funnylettering just had the same problem a few weeks ago and had to buy a new case.

I looked at the video. It didn't want to play at first, but it finally started. That chain is way too loose to run the engine. It could self destruct the engine. See my rocker arm blog below for details on that.

[The_big_dill]

Originally Posted by n4mwd

M5-0.8 x 8mm long.


$9@Lowes, but your local hardware store may have a better deal. Ask for a 5mm-0.8 x 8mm Button-Head Allen-Drive Metric Socket Cap Screws. If they only have one that is 10mm long, you'll also need some washers for spacers.

When you replace it, just snug it in because it is only a cork once the plunger is released.



The round doughnut thing with ball bearings in it is a ratchet. You can't force that to the mating position without damaging something. Hopefully, its just the external CCT that got messed up. The springs are rarely the problem. Sometimes balls will fall out of the ratchet and it will need replacing.

Did you do the test with the socket extension like I described? This is to see if the internal CCT mechanism still works. If it does, then probably all you need is a new CCT housing which can be bought on ebay.

If the internal CCT is bad, then you need to pull the clutch cover and see what is going on. Funnylettering just had the same problem a few weeks ago and had to buy a new case.

I looked at the video. It didn't want to play at first, but it finally started. That chain is way too loose to run the engine. It could self destruct the engine. See my rocker arm blog below for details on that.

Thanks for the info, I may just go out and get that bolt, but from what i understand, you are certain that damage has been done to the CCT...

I will try your method of checking the CCT today, i just need to take apart the thing again.

[The_big_dill]

Here are the photos of the tensioner assembly:

https://skydrive.live.com/redir?resi...4FC025!205&v=3

there are 5 photos. In the second picture, you can see a little bit of damage to that shaft, but it is only visual, you cannot feel it.

In the fifth picture, you can see how the balls have dented in the inner area of the CCT housing, is this normal?

I was able to get more tension with the socket extension down the CCT hole. Here is a video:

https://skydrive.live.com/redir?resi...4FC025!208&v=3

Sorry, this is difficult to film with only 2 hands...

By the end of the video, i was holding the camera with my chin and i don't think i was putting enough pressure on the tensioner lever, so you could see a bit more slack.

[Motofool]

Originally Posted by The_big_dill

Here are the photos of the tensioner assembly..........

That slack will destroy your engine, Phil

Maybe @n4mwd knows an easy way to inspect the rubber guides.

The tensioner puts pressure on the ends of the arc-shape guide, which bends and moves both branches of the chain closer, increasing the tension.

Maybe your tensioner is doing all it can do, but the rest of the mechanism is not.

Also, could you measure the chain with more precision to rule out any out of spec stretch?

[The_big_dill]

Originally Posted by Motofool

That slack will destroy your engine, Phil

Maybe @n4mwd knows an easy way to inspect the rubber guides.

The tensioner puts pressure on the ends of the arc-shape guide, which bends and moves both branches of the chain closer, increasing the tension.

Maybe your tensioner is doing all it can do, but the rest of the mechanism is not.

Also, could you measure the chain with more precision to rule out any out of spec stretch?

Are you referring to the latest video i put up?

The engine is currently apart, but still covered while i am not there, so i will try to check the guides tomorrow.

[n4mwd]

Originally Posted by The_big_dill

there are 5 photos. In the second picture, you can see a little bit of damage to that shaft, but it is only visual, you cannot feel it.

I only saw one extra photo and a video. You can upload photos directly to the post which would make it easier.

In the fifth picture, you can see how the balls have dented in the inner area of the CCT housing, is this normal?

No photo, but the inner race can be replaced or at least the sell a replacement part. However, I've never figured out exactly how to replace it. EBAY is usually the best option in a case like this.

I was able to get more tension with the socket extension down the CCT hole. Here is a video:

With that test, you want to apply finger pressure to the extension to see if it makes a difference in the chain slack between the two cams. More finger pressure should tighten the chain, less should slack it. If that is pretty much what you are seeing, then your internal CCT mechanism is probably OK.

Sometimes the internal CCT can get gummed up and gets stiff. You can free it by squirting some high quality penetrating oil (NOT wd40) into the hole and toward the hinge pin (see my video above to see the location of the hinge). Then work the tensioner back and forth by alternating between pressing the chain down and the plunger. Tight - loose - tight - loose - etc. Then squirt it with regular motor oil and repeat.

After you get the new CCT housing and new bolt and reinstall it, check your cam timing before you button it up because it has a tendency to hop teeth when the CCT is removed.

[The_big_dill]

Originally Posted by n4mwd

I only saw one extra photo and a video. You can upload photos directly to the post which would make it easier.



No photo, but the inner race can be replaced or at least the sell a replacement part. However, I've never figured out exactly how to replace it. EBAY is usually the best option in a case like this.



With that test, you want to apply finger pressure to the extension to see if it makes a difference in the chain slack between the two cams. More finger pressure should tighten the chain, less should slack it. If that is pretty much what you are seeing, then your internal CCT mechanism is probably OK.

Sometimes the internal CCT can get gummed up and gets stiff. You can free it by squirting some high quality penetrating oil (NOT wd40) into the hole and toward the hinge pin (see my video above to see the location of the hinge). Then work the tensioner back and forth by alternating between pressing the chain down and the plunger. Tight - loose - tight - loose - etc. Then squirt it with regular motor oil and repeat.

After you get the new CCT housing and new bolt and reinstall it, check your cam timing before you button it up because it has a tendency to hop teeth when the CCT is removed.

Very informative and i am glad you mention gumming up, because i feel like this is the case.

Notice at the end of the video there is more slack than before?

Should that lever that is engaged by the CCT move (Relatively) freely?

The same order of the photos have been attached to this post.

[n4mwd]

Originally Posted by The_big_dill

Very informative and i am glad you mention gumming up, because i feel like this is the case.

Notice at the end of the video there is more slack than before?

Should that lever that is engaged by the CCT move (Relatively) freely?

The same order of the photos have been attached to this post.

Yes, the lever should move freely, but it gets tighter toward the end of travel obviously. Note how it moves in my video with just my finger. Just be sure not to force it or you could break it. Finger pressure only. Just work it back and forth until you get it to move easy. Just don't use WD40 on it, but high quality penetrating oil (like nutbuster) is OK. Use it sparingly because you are contaminating your oil with it.

No problem with the pictures this time. The race does look a bit worn.

I had this exact same problem with my 2006 and had to put a used CCT housing on it after I got it to move freely.

[The_big_dill]

Originally Posted by n4mwd

Yes, the lever should move freely, but it gets tighter toward the end of travel obviously. Note how it moves in my video with just my finger. Just be sure not to force it or you could break it. Finger pressure only. Just work it back and forth until you get it to move easy. Just don't use WD40 on it, but high quality penetrating oil (like nutbuster) is OK. Use it sparingly because you are contaminating your oil with it.

No problem with the pictures this time. The race does look a bit worn.

I had this exact same problem with my 2006 and had to put a used CCT housing on it after I got it to move freely.

Well, i will be going around stores tomorrow trying to find a replacement screw for the one that is stripped...

2 things that are on my mind. you mentioned that when someone rotates the crank and i have the extension down the hole with moderate pressure on the lever, what is suppose to happen in a functioning situation?

The other question, can i just use a flashlight to inspect the chain guides like motofool suggested, or would that not suffice?

[Motofool]

Originally Posted by The_big_dill

Are you referring to the latest video i put up?....

Yes, the last video.