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Odd knocking sound at low rpm accelleration

15K views 26 replies 6 participants last post by  nicodarious 
#1 ·
I've always been the type to think that I take care of my toys, small to large; keep them tuned, well lubed, and clean. But one thing that's bothering me (that the dealer said was normal) is this knocking sound when accellerationg in a low gear at low rpm.

Here's an example: I have a corner that needs second gear to turn onto. It's got a bit of an incline at the beginning. Its exteremly prominent on this hill. Gear down to second, cut across oncoming lane and accellerate up and around onto road. So the speed is about 25 MPH, depending on how ballsy I feel for the day and if I can get across the lane without traffic interfering. So 25 MPH when I hit the base and start rolling on the throttle. As soon as I do, I hear a knock knock sound the same speed as the engine rpm.

It sounds like a lifter but I can't tell; I've never had a lifter go bad in any of my vehicles.

On top of that when rolling on the throttle from idle speed, there's a bit of a ping to the motor. Can especially be heard at a stop when setting up to take off. Just a really high pitch ping. This though doesn't last more than a split second. I've tried different grades of fuel from different stations but both ping and knock are always there.

Any other 1900 owners out there that can verify that this is normal, as the dealer tried to pass me?

Thanks in advance!

John
 
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#3 ·
The sound disappears at speed? Have you inspected the plugs or ran a treatment of Seafoam or other carbon buster in the tank yet? Do you have ethanol free gas available in your area ( http://pure-gas.org/extensions/map.html ) ?

I'm not saying you have a fuel problem. It's just nice to eliminate it from the equation.
 
#4 ·
That's what I was trying to do with the different gas stations and grades. Ill fill this next tank up and top it with seafoam to see how she does, although I don't think it should matter. Barely have 3k miles and she's done it since about 1k (that I noticed at least).
And yes, I gave her new oil at about 700 miles, so its not the oil I don't think.

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#5 ·
With only 3k miles the Seafoam shouldn't be offering much benefit. I'm not sure you're hearing a problem or a normal characteristic of the motor.
 
#6 ·
So after a long haul ride to TN and back to AL, the bike is still having that knock. It seems to be getting worse, as in longer through the low power band, not in pitch. Thinking it might be the oil? Its about due for a change. I am thinking of going with a heavier oil this time instead of 20w50 v-twin oil. Maybe that might help out? As far as the higher pitched ting when revving from idle, I think that's low octane ping, but not sure. Will put octane booster on top of high grade for the next few tanks and see what that does.

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#8 ·
Sounds about right. I remember reading this somewhere when doing research on the bike before purchasing it earlier this year. Sounds seem to be coming from the cooling fins and above, so going to assume piston head noise. Wouldn't thicker oil help with this sound especially since its getting above 90 degrees in humid area? Sure it'll eat mileage up a bit since its higher viscosity, but personally I would give up a bit of mileage for a protected engine if it would help at all.

Thoughts?
 
#9 ·
Use whatever recommended oil you want. There's plenty of opinions on the subject. If it just happens to muffle the noise, then great. A noisy jackshaft would be one of the few noises I would think has a chance to be muffled with a heavier viscosity oil.
 
#11 · (Edited)
I had a loud, annoying and odd sound from my 07' Stratoliner. It was later found that the nut was coming loose from the drive belt counter shaft cog or what ever it is called. The nut is not keyed on but peened. Happened around 22k miles on the bike. I found out about this problem which Yamaha is finally and grudgingly admitting to. By the time the problem was id'd there was damage in the belt housing as the nut had loosened to the point grinding against the housing cover. My service mgr was able to convince Yamaha that it should be covered under my extended warranty. Since he has a strat also he checked his and found the nut loose and is checking all 1900's that come in. He said all he inspected needed tightening. I would have posted publicly but couldn't figure out how to reply. This may be where the noise came from. Mine was very loud but I heard it mostly at deceleration and a certain rpm. All 1900's need to checked. Hope this helps.
 
#12 ·
Hmm. Interesting. Where did you hear the noise coming from the most or could you even place it? Left, right, top, or bottom of engine? The reason I ask is because mine sounds dead center of engine kind of more on the top than bottom. I can't hear it while on a stand and running, and its really hard to isolate when going down the road at even a slow 30 MPH.

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#13 · (Edited)
I really couldn't tell. But it was frustratingly loud but the service folks weren't picking it up. But you may want to inspect the belt housing as a precaution. I have heard of 3rd gear issues also causing noise. A friend of mine found reference to the belt nut online. But as I said I only heard the noise when decelerating and in a narrow rpm range. 2800 rpms to 3200 come to mind but can't remember exactly. A google search for loose belt nut came up with this: http://www.stratolinerdeluxe.com/technical-discussion/grinding-noise-front-left-side/
 
#14 ·
So after a clean oil and filter change, went on a 1k mile ride to Florida and back. What I have noticed since then is the knocking is still there. The funny thing is, it happens in a left corner and not in a right. I tested this out and ran the rpms higher than normal while leaned to the left and sure enough, it didn't matter what speed, the engine knocked. Did the same test on the right leans and no knock.

At the moment, I decided to go with pure 20-50 synthetic oil by Castrol with a k&n oil filter, if that helps out at all.

Thinking bad oil jets maybe?

I have been putting nothing but premo gas in the tank, so the pinging is all but non existent now.

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#15 ·
So it seems to be getting worse. The knocking sound now hits with even takeoff in first around left corners. Took it in to the shop under warranty and the guy 'could not reproduce it', even though i heard it the moment i rode in. The bike is worrying me. Im just hoping that it wont pop on me 2 days out of warranty....

I'm rooted, bitchez!
 
#16 ·
Hey, Mak here from Illinois.
I'm a new member to this forum. Saw your post about your engine knock in left turns. I have the exact same noise on mine! Wondering what you found out about yours? I too went back to the dealer. They told me didn't hear anything out of the ordinary. Said it was under warranty. To me, that isn't a sufficient answer after spending the money that I just spent! Tipicle of a dealer I guess.
I would definately appreciate your input.
Thanks, Mak
 
#17 ·
Nothing to be found, although i did find someone that thinks it might have to do with the bone inside the transmission. They are going to take a look at it later on when i can get the time to travel the 50 miles to see them again. Still under warranty, so no cost to fix if it is the issue. Will keep you posted.

I'm rooted, bitchez!
 
#19 ·
I asked the same question. From what i gather, it's the part that pushes the gears around from one to another (higher and lower). I may have misunderstood the mech when i asked, but that's what is going through my head as to what it is. I've never disassembled a transmission before, nor do i have the skills to.

I'm rooted, bitchez!
 
#20 ·
If you don't mind me asking, who suggested that? The noise is irritating! I wonder about it kind of the same as you, will it break right out of warrant??
The dealer tells me not to worry, the motors are bullet proof.
If you find any new info, I would greatly appreciate it. I will let you know if I find out anything else also. Have not heard anyone else mention it except for you. I was happy to find your post because I thought maybe I was the only one.

Thanks, Mak
 
#21 ·
Went to a Yamaha specialized dealer and had a talk to one of the guys that work specifically on yamaha bikes. He said its so rare that her has only seen one other bike come in with a knock sound in his17 years of working on them.
I thought i was the only one hearing it, until my wife rode with me and asked about it during a stop. Wouldnt worry about it too much right now though. Been riding mine with the knock for at least 7500 miles (since i started noticing the knock), so its not one of those things that might blow right away. Until i find out more, ride her.
BTW, how many miles do you gave so far? Have you done your first oil change yet? The reason i ask is because thats when i first noticed the knock (the 800 mile break in change).


I'm rooted, bitchez!
 
#22 ·
I have about 2500 mls. now. I'm pretty sure it was obvious before the oil change at 600 mls., though it might have gotten worse after that oil change.
I have been battling with getting the bike to run right though. Had cobra swept pipes put on and a power commander V before I even brought it home. After about 2 months of back and forth with the dealer, I finally found a guy that was extremely good at tuning bikes with a dyno. Cost me some money but it is finally running perfect!
I will keep that info. you gave me in mind, and I'll let you know if anything changes with mine.
I think the oil they run from the factory is like a break-in oil. I don't know what the difference is, but mine may have gotten worse after the 600ml. change.
Thanks for all the info! Very glad to have gotten a hold of you!!
Thanks, Mak
 
#23 ·
Likewise. Just a little comparison FYI, I have yet to change the pipes or do anything serious to the system besides drill the back of the pipes. So farm I have tried in the last two changes 20w-50 castrol full synthetic (made for v-twins ). The first was a 20w-50 half half castrol blend. I noticed during the last change that the sticker says 20w-40 though.

What do you run?

sent from my rooted / customised nexus 7
 
#24 ·
My receipt for my 600 mile check says AP20w50. I think it's just your standard oil. The guy that ran mine on the Dyno recommended semi synthetic next time around before winter. Don't know if the oil has anything to do with the knock or not? I guess time will tell. I will ask my dealer about the trans. bone suggestion and see if they know anything about it next time I go in.
 
#25 ·
Hey Nicodarious,
I messaged you last year about that knock on left turns. Just wondering if you got it fixed or you got any more info on it? Iv'e asked a couple of so called mechanics but they claim they can't hear it. Say everything sounds normal. I'm very skeptical! It only does it when leaning left and accelerating into the turn.
Just curious what you did with yours.

Thanks, Mak
 
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