Alright so I been hesitating starting a thread as I am not one to start new topics on mechanical issues, but I just can not find my answer. Every post is related to the Cam Chain Tensioner and that is not my issue. Anyways, should there be slack on the exhaust side of the Cam Chain? The intake side is tight however. I get a lot of cam chain slap on startup, cold, hot or immediately after shutdown, that lasts a few seconds then goes away. I know the tensioner works off oil pressure but this is the first time I have ever heard it. The last thing I want to do is shell out money on new cam chain and guides and everything else I would need trying to convince myself there is an issue when there is not. I have enough slack to lift chain off the guide and just about fit my finger between (again just the exhaust side), doesn't seem normal to me.
That's odd. Both sides had no slack for me. If you mind me asking, are you using a manual tensioner? If so are you certain you properly adjusted it a quarter inch turn before locking it?
You don't really want to buy a new cam chain just yet buddy
The way to know for sure is to align all of the timing marks. If you cant get one to line up its stretched. Theyre only about $25. I paid that from a dealer.
Alright so looks like the Valve cover is coming off. Do you guys actually replace the valve cover gasket every time you pull the valve cover? I can't imagine so. Yea the chains are cheap, its the guides that make it pricey. Figure if your in there replace everything. Hopefully I'll have time to tackle that this week.
So is the verdict in that there really should be no slack on the exhaust side? I figure there has to be some slack in the chain and will show up on the only side of the chain that has nothing putting pressure on it since the Cams don't move at engine off. But nevertheless chain slapping can not be good for anything.
Alright so looks like the Valve cover is coming off. Do you guys actually replace the valve cover gasket every time you pull the valve cover? I can't imagine so. Yea the chains are cheap, its the guides that make it pricey. Figure if your in there replace everything. Hopefully I'll have time to tackle that this week.
So is the verdict in that there really should be no slack on the exhaust side? I figure there has to be some slack in the chain and will show up on the only side of the chain that has nothing putting pressure on it since the Cams don't move at engine off. But nevertheless chain slapping can not be good for anything.
are the guides worn? Ive seen 5 different engines torn down at the end of a race season... all still running the original guides. You can measure the cam chain for wear. The manual ones take abit more precision to get correct since you can overtighten really easy. Most set a looser clearance on the bench then adjust when the engine is running.
The tensioner should take the slack out of the chain. Think about your drive chain. If you push up on the chain below the swing arm (acting like a chain tensioner), what happens to the chain on top, above the swing arm? It gets tight. Same thing is supposed to happen with the cam chain. the tensioner pushes in on the intake side, and the exhaust side should be tight.
That is why, when you install cams, or cam chains, or tensioners, it is imperative to set the timing marks with no slack in exhaust side of the chain. Or more precisely in the side opposite the tensioner. There are some rare engines that spin the other way, and the tensioner would be on the other side.
I forgot to add that I had my valves adjusted about 2000 miles ago, I never put it past the shop to have messed something up. I'll pull the valve cover as mentioned and take a look. Will report back with any findings.
Yea they are not held reliable, which is a joke. That's like me being an electrical engineer saying I am not held responsible if my plans burn down your building, like wtf. And even if they could be it would be hard for me to prove beyond any reasonable doubt they are to blame months and 2000 miles after the fact.
you could make a case with pictures and a timeline for small claims.
Didnt realize the guides had that much time on them...lol. Keep forgetting you street guys run up the miles!!
Alright so took the valve cover off. Good news is the timing is only off by maybe 1 tooth if really at all (I'll let you be the judge). The other thing is the exhaust side slack is gone after I turned the engine over a couple times which explains the chain slapping that fades away on startup, but does not explain why it happens after shutting off the bike and turning it back on. There are still however a couple spots where there is just ever so slightly more slack then others (can just hardly wiggle the chain, whereas in most spots It is as tight as the intake side and wont move.
I did not remove the chain guides, wasn't sure if I had to remove the cams or not or if I could just just remove the chain tensioner and slip out the guides. The pics below should hopefully explain more, but what do you guys think. Should I be worried about that timing (if so, easiest way to fix it without removing the cams hopefully), replace chain/guides?
So The first 5 pictures all with Cylinder 1 at TDC. Picture 6 is showing when cylinder 4 is at TDC and the last 3 picture are again when Cylinder 1 is TDC but I lined up the marks on the camshaft to show the cranks position.
Yea from what i can see you were off by tooth (According to picture 6). It's kinda hard to tell if your guides are worn out since you can only see just the bottom parts of it. You will need to remove your cams to get those replaced (Easiest way to get them out).
I'm assuming you corrected the timing. How is the bike running now? Iif you put everything back together.
I didn't get a chance to do anything but inspect. Was going to wait for others opinion as well. I'm just hesitant to remove the Cams because I don't have a quality torque wrench that can handle that low of a torque range.
So I was already to pull the cams. But having another look at it the timing is pretty darn close. The chain was still tight on the exhaust side so what ever causes it to get loose happens when the bikes at rpm and running. Before I waste my time pulling the cams for nothing I wanted to get your guys opinion.
So I think I found a problem. Was checking the chain slack between the cam gears. All is good till I reach this point where the slack is noticeably looser and the crank becomes considerably easier to turn for a brief moment. I don't know if that's the chain, warped camshaft, or what.
That sucks...did your set the proper timing already? Put it back together and see how it runs now. Once it comes to the inside of an engine thats were my knowledge goes caca! lol. May be Turboblew, Yamahacrazy, or 8Ball can jump on the topic as they're experienced with engine work so it seems.
Haha yea I'm with you, engine work is all new to me. People always tell me it's just nuts and bolts...yea maybe to you, to me I might as well be defusing a bomb.
Not yet because I'm still doing research on it before I waste my time pulling the Cams. I'm about to just say screw it and order new Chain and guides but not a fan of wasting money haha. So hoping someone with a much better knowledge than I will help inform me of how to proceed. I was about to put the bike back together yesterday and just live with it when I decided to check the tension between the Cams and noticed the uneven tension. But I know I would not be able to sleep at night knowing I put the bike back together with a potential problem.
I think if I can't find the info I need by this evening I will just order new Chain and guides as I can't do another week of the bike sitting in pieces and I can't put it back together with the feeling something is off. I just find it hard to believe that 28k miles the chain is failing. For all I know the varying tension between the cams is normal from the valves pushing up on the cams slightly, who knows.
Edit:
So been googling for awhile now (its Friday no work gets done on Fridays, haha) and everything does seem to point to this slack being normal due to the cylinders pressing up on the Camshaft. Just the sources are questionable, so still like some insight.
Since your timing marks are on point (when you rechecked, right?), it sounds to me that your tensioner isn't working efficiently. I don't really like that oil pressure assisted unit they put on the 3rd gen. Theoretically, the weak spring in it holds the tension and oil pressure helps push it to the next ratchet position. But from what you are describing, it sounds like the spring isn't holding enough tension with the engine off, and until the oil pressure builds, the tension isn't sufficient.
My suggestion is that you replace the CCT. Replace it with another OEM one, or a manual one. Your choice. But just be aware that with the manual one, you'd need to check/adjust it periodically. (I'd suggest every oil change). The OEM one doesn't need that kind of attention, but you would need to replace it when you notice the noise again
Correct, the marks are so close within probably a degree of each other (exhaust retarded slightly) that I just don't think I could get it any better. Alright darn, I just replaced that a couple years ago too. I will take your advice though and order up another one. Thanks 8ball really appreciate the response.
Before you install the new one, you want to stick a screw driver or drift pin down the hole and push on the chain guide to take up all the chain slack. That way when you put the new CCT in and it releases, the weak a$$ spring doesn't lose any energy pushing the chain slack out. It will spring out as far as is can.
Alright so just a little update, I pulled the camshafts and chain/guides over the weekend. The guides were in good condition but replaced them anyways since I had new ones and did not feel like going through the return process nor did I feel like doing all that work and not putting in new parts. Compared the old chain to the new chain and almost zero stretch or any indication that the chain was worn. So decided to put it back together with old chain, but after the 20th time (perhaps an exaggeration but certainly did not feel like it) of putting in and taking out the chamshafts and caps to get the timing spot on I said screw it and put in the new chain. Perhaps by that point I was just a seasoned veteran at setting the chamshaft timing but the timing is now spot on. Installed a new camshaft tensioner as well, which I believe 8ball was right. Even though the old cam chain tensioner was relatively new I think the spring just went on it and could no longer hold the tension when the bike sat idle.
But I won't know for sure if problem is resolved for at least another week. While waiting for parts I decided to do some TLC maintenance on tough to access items while the bike was stripped down. Removed the throttle cables to lube them only to find the wires were splintered at the throttle bodies. So needless to say I am back in the waiting game for parts before I can reassemble.
Once I can get the bike out and put some miles on it I hopefully can come back and close the thread with a fixed bike.
I did the same thing as you. I questioned it and questioned it. and when I put that new chain on I was like well some bi tch those damn yamaha boys know what they're doing with those marks lol
Yea, it's just crazy because the old chain was impossible to see any stretch or signs of wear. Even an 8 pin measurement matched up. It's probably one of those things where I didn't really need to replace it, but for all that work it's probably best. But we'll see after I can get some miles on it. Throttle cable should be here soon.
mine was way worse but bike didn't run funny. probably not making full power but I didn't really notice.
but you're right, it was apart might as well put in a new chain. they don't last forever.
any write ups on how to install the APE tensioner, also read there is a hole that needs to be plug with JB weld. anyone have a reference photo. new to the yamaha scene.
Yea there is a thread on it somewhere. You will have to do some searching to dig it up. If not I'm sure there are youtube videos. The hole you need to JB weld is the small oil inlet hole inside where the tensioner sits.
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