Changed the CCT, HOLY CRAP, the engine is falling apart inside

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lococnc

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I thought I started hearing noise so I decided to replace the CCT.

Upon opening up the lower right engine cover to zip tie the chain, I found this lying in the bottom;

IMG_20151113_233306.jpg


Which is supposed to go here

IMG_20151113_233220.jpg


It was running fine, has 70k miles. Looking at the top guide there is very little wear on it so I suspect this has been like this for a very long time. However, it is obvious that the studs have touched the chain. It seems to have polished the surface of the chain, take a look here

IMG_20151113_233238.jpg


I don't think this looks bad. I found a valve cover on ebay and ordered it. I can't get the guide on the valve cover. How is it supposed to go on there anyway? I guess I could clean up the studs and jb-weld the chain guide on there.

Oh, and here are my valve measurements;

Exhaust 0.008 0.008 0.007 0.008 0.008 0.006 0.009 0.006

Intake 0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.006

So I have 3 exhaust valves to adjust (going to do the .007 one as well)

All the intakes are right at the lower spec. Not going to touch them as I bet they are the same as from factory fresh.

 
I'd say a CCT replacement was/is a good thing!
weirdsmiley.gif
Looks like that guide is supposed to be held in place mainly by the chain, and popped off when the chain was lashing about because the CCT was failing to maintain proper tension.

Make sure to check the chain didn't skip a tooth.

 
Good catch. Lucky that didn't get fouled in the lower chain and sprocket.

Those nubs in the valve cover may have started out somewhat longer than what they are now. If they were, and the chain had remained tight, the guide would not have been able to pop off them. I'd clean and degrease the contact are and use some strong epoxy when putting it back on.

 
So the question of the day is: "Do I try to reattach the plastic piece to the valve cover with some JB-Weld?, Or wait until the new (used) one arrives?" I ordered it on Saturday but shipping status this morning (Tuesday) shows pre-shipment details sent, which to me means it is sitting there waiting to be picked up.

 
You got a new one coming, is it worth the potential damage if it comes loose again, or literally doing a "do-over"?

Its not like its a 10 minute job to get to that valve cover either..

IMO, I'd wait for the new part and do it right...

 
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I ordered it on Saturday but shipping status this morning (Tuesday) shows pre-shipment details sent, which to me means it is sitting there waiting to be picked up.
I do a bunch of shipping and most of time, the item, although slow initially going out, usually arrives quicker than expected. I'd think you'll have it by the weekend....

 
When I say "new" it is an ebay purchase of a used part-out bike, the pics it looks clean and the tensioner guide is still attached to the valve cover.

 
I wouldn't adjust the .007 exhaust. I'd also double check the 0.006's just to be sure.

 
Oh, and here are my valve measurements;
Exhaust 0.008 0.008 0.007 0.008 0.008 0.006 0.009 0.006

Intake 0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.006
Somehow I glossed right over the exhaust valves being tight because of the AWOL chain guide.

That is a very unusual situation, being that the intakes are all fine. Usually folks find the intakes shrinking and the exhaust staying fairly steady. My theory is that the exhaust valve faces and seats get some protective buildup from carbon deposits, and so do not wear like the cleaner intake valves and seats seem to do.

 
No, the intakes are on the bottom "tight" spec, so unless they started there they have decreased. I am NOT messing with them though, in spec is in spec.

I did adjust the .007 because I only ended up needing 1 shim to get all the exhaust to 0.008.

Valve cover arrived, going to install tonight.

 
I think they start there.

My first valve check at 25k miles on my '05 all 8 intakes sat at .006 at varying degrees of snugness, but all were a no go at .007" Second check was the same as the first. It wasn't until the third check at 75k miles that I needed to adjust them, and they were all between .005 and .006 at that point (.006 was a no-go on all 8).

On the same three checks the exhausts were in the middle of their range and did not budge. I thought this was strange, but after talking too many others it does seem that the exhausts, perhaps counter-intuitively, do not tend to wear as much or as quickly as the intakes.

Also, if you really want to know where the valves are you should measure with metric feelers. You have two and a half .01mm steps per .001". The added precision can help you understand which are wearing. and how quickly. The alternative is to record which measurements are a loose .006 and which are a snug .006 as that gives a similar granularity to the measurement

 
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I think they start there.
My first valve check at 25k miles on my '05 all 8 intakes sat at .006 at varying degrees of snugness, but all were a no go at .007" Second check was the same as the first. It wasn't until the third check at 75k miles that I needed to adjust them, and they were all between .005 and .006 at that point (.006 was a no-go on all 8).

On the same three checks the exhausts were in the middle of their range and did not budge. I thought this was strange, but after talking too many others it does seem that the exhausts, perhaps counter-intuitively, do not tend to wear as much or as quickly as the intakes.

Also, if you really want to know where the valves are you should measure with metric feelers. You have two and a half .01mm steps per .001". The added precision can help you understand which are wearing. and how quickly. The alternative is to record which measurements are a loose .006 and which are a snug .006 as that gives a similar granularity to the measurement
I just finished my first valve check at 26k last night. My intakes were the same .006 of varying tight and loose. But .007 would not go. I recorded it as .006T, .006. or .006L. Exhausts were all .008 or .009. Good to know that yours didn't move much in the next 26k. I fully expected to adjust many intakes next time. But maybe not.

 
Well it's all back together for a few days now and I have ridden several hundred miles. Engine is noticeably quieter. That valve cover gasket is a bitch. I ended up using some gasket bonding agent on it. Next valve check I am removing the throttle cables and thermostat. Tripple checked the timing and it is spot on. No leaks! Did the ******** on coolant and an oil change.

 
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