strange noise on top engine

Hi guys...after solving problems with the carbs,tci and valaves clearences...and after a hundred miles ridung good a strange noise shows up in the upper engine in the right side...its like an usual tic-tic as a valve out of clearence but when the bike get hotter and you squeeze the throtle the noise became louder like a knock. Its get louder after 55/60 mph... Yestarday I pulled the head off to check the screws and everythung was tight...i did have the fillers to check the valves....any ideas of where thus noise could come from???

 

Exhaust leak where the pipes connect to the head or a cracked head pipe. With the engine running you should be able to feel the air leaking out. Another trick is to hold a piece of tissue paper near the suspect leak area. It will start to move when near a leak.

Is your timing chain properly tensioned?

 

Are you positive it's not coming from the bottom end? Let's hope not. Can you narrow it down by using a hose or a wooden dowel to put against your ear and track the area down.

 

Chain is ok...thing is you can barely hear it when the bike idles...and when it gets louder you can hear it at 55mph with no windshield by just turning your head. I'll try to narrow it down as you said...never did that before

 

Try snugging up your exhaust collars......also, check the rest of the exhaust unions

 

^and after that, use a length of hose as a stethoscope. If the noise is coming from the exhaust camshaft area, then you can probably safely ignore it. Yamaha had a Technical Service Bulletin on that particular noise.

 

Kmoe what you mean by exhaust camshaft area...i dont have all that tech english....sorry

 

The front camshafts (spinny things that open the valves) are for the exhaust valves. There was a batch of cam caps that let the cam slide from side-to-side a bit too much, making a bit of noise in the process.
I'm not sure if that's what you're hearing or not, since it usually shows up (per Yamaha) at relatively low mileages. The reccomended fix is to leave it alone unless the customer complains about the noise. The extra bit of movment causes no damage; besides the replacement cam caps aren't available anyway.

 

Well thing is that when I ride with my wife she can barely hear it so since I've been doing a lot in the bike lately maybe I become a little picky...tomorrow I will try to narrow the noise with the hose...beside that and what you mentioned about the camshaft there could be something else that I should think/worry of??

 

Camshaft endplay is nothing to worry about… It's a known issue, but is not a problem.

 

Apllying the modern technology heres a video...maybe ot help you or me to identify that noise....

 

Sorry guys tried to upload the video but for some reazon didnt work

 

Put the video on another site and just post the link here. You can use youtube, flicker, photobucket or a sharable link to your gdrive if you have one.

 

Here is the link

 

I hear two things: A squeak, and popping in the exhaust (indicative of a lean mixture).

I think you have a vacuum leak at a gasket.
Take some carb claner and spray it methodically around the intake side of the engine.

 

What is that for? I mean the carb cleaner around the intake boots. Boots were always a problem and always had a leak sooner or later. About that noise, is something bad or something that will broke on the road?

 

The carb cleaner will get sucked through any leak and make the engine speed up. Continuing to run the engine with a vacuum leak will eventually burn a hole through one or more pistons, or cause a burnt valve. The intake boots can be repaired if they are cracked. The noise sounds to me like air rushing through a flexible gap, perhaps from a crack in an intake boot, or a gasket that isn't fully seated.

 

Note the plastic sleeve on choke rod spins when you revved the engine

 

Have you had cam sprocket bolts out?
Had that happen on a Honda many years ago. Idling on side stand no noise but soon as I rode it rattle of bolt head that was out about 2mm tapping against cam chain tunnel

 

The camshaft is tight. The intake boots are not cracked but somewhat milimeters shorter than originals. Is the only I can get here. So basically that noise is a vacuum leak?...

 

Yes, it does sound like a vacuum leak. It does need to be found.
Just like K-Moe said, Use some carb cleaner and spray small amounts around the suspect leak area. The engine rpm will change when it gets sucked in. Make sure the cleaner you are using is flammable or it won't work. Propane gas and starting fluid also works but be careful with them.

 

Just used wd40 sprayed all around the boots and close to the cylinders...no change in the engine at all...

 

WD-40 is not flammable enough for this test. In some countries it isn't flammable at all due to differences in formulation.

 

Ok...I'll catbs cleaner then and try...

 

Question...does the camshaft has ball bearings?? Could be that what is making the noise?

 

A squeaking/sound is almost always a dead give-away for a vacuum leak at the carb-to-manifold boots. My bet is that the mating surface bewteen the two has failed one at least part of one boot. It doesn't take much to make it make noise. For lack of a better way to put it----you create less vacuum, when you make a 'kissing" sound with your lips....yet you make a lot of sound. Now, increase that multiple-fold for the vacuum draw of the engine AND couple that with 4 cylinders pulling vacuum-----no wonder it's a loud noise.

The camshaft does not have ball bearings. It rides on a thin film of oil. The noise that the cam itself can exhibit is a tapping sound due to some extra end-play. This is a known symptom, and it's also known that it is a non-issue.

 

Ok. Im following your directions here... I will apply carb cleaner on the intake boots while the bike is iddling, one by one until I hear that the bike revs up...there should be a crack right? Lets say I find it, what should I do to seal it? And besides that should take off those boots and make a new gaskets?

 

Let's concentrate on finding the leak first. What to do about it will depend on exactly where it is.

 

Ok.... I wont be able to do it until monday...any danger in riding the bike on weekend?

 

That depends on how lean it's running, and how much you want your pistons to stay hole-free.

 

A lean mixture should show in the spaks splugs right? Mines are king of black

 

After going back and listening to the video again, wouldn't be c on earned with riding that sounds. To my ear it sounds more like a loose exhaust collar. I don't hear much of an intake vacuum squeak. You might find a bit, but I'm not too worried about that.

Personally, I'd go for a ride. Actually, I think I WILL!

Dave

 

Ditto, supposed to reach 50 today. Ride bike is on my "to do list".

 

Hell now you got me jealous...I ll buy the carb cleaner but even when I had visible cracks in the last boots the bike wont make that sound...thats whats bother me

 

And the fact that I cannot ride it because something could break

 

Don't buy a brand new bike......you won't be able to ride it because something might break.

Just because you see cracks doesn't mean they go all the way through. MOST likely, either a gasket is failing, or an exhaust collar is a teeny bit loose. Did you try tightening them yet?!?!?!

PERSONALLY, I'd go ride.

Dve

 

I'll tight them now...not afraid something break...afraid how to get parts...you wont believe how difficult it is...and just for a few hours of pleasure dont want to spend month without riding

 

Don't crank hard on them, just snug them a bit. I often get sounds like that if a collar gets loose. They can loosen up over time and heating/cooling cycles. First time I ever had one get loose, I thought I had blown a hole in the engine since it was so loud. Snugging up the collar again on cyl 1 fixed the noise.

Hopefully it's that easy for you, too

 

All of them but two were 1/4 turn loose...ride the bike and that noise didnt go away but It got smoother...or less louder... Im positive its not a vacuum noise it is in the right top hand side of the engine and by ear I could point a valve ot yhe camshaft close to the exhaust

 

Got to work tomorrow so I take the bike out on the road for a 15 miles to work and another 15 to come back and see if its get louder

 

I'd snug them just a tad more then...... There is a copper crush gasket in each exhaust port. If the collars arent snug, then the washer will not be sealing as tight as you think it might be......and they won't expand to fill a gap.

 

I"ll do

 

Rode yestarday to work...cool morning, the noise was more as valve noise. Came back in the afternoon with hot weather and the noise again got louder...

 

I'll check valve clearenses again

 

One thing I seen on your video, you have a plumbing type of hose clamp on the carb boot ...these can cut into the boot the stock clamps are solid and bottom out when fully seated . The type you are running if wrenched down to much can cause pinching of the boots . Just my thoughts ...

 

I bought them just like that. Under the cap there is a fixed metal pin...

 

That's typical.....not a problem.

 

Yes, I'd definitely get the correct clamps.

 

The metal "pin" under the cap is the vacuum port that you use for either the vacuum source for the petcock, or for hooking up you manometer for syncing your carbs. Make sure all 3 caps are on snugly. There should be one without a cap, because your petcock vacuum line should be going to that one. If you have bypassed the petcock vacuum line,Cohen make sure you have capped the remaining vacuum port.

 

Just though it was funny