How much driveline nois is normal?

[Justa6MB]

I've got a 2007 Vmax with 4500 miles. I have a batwing and windshield and stock exhaust on it so it's quite quiet. Except for a pesky driveline noise. I can hear the noise mostly on what I'd call light or balanced power. So fairly quiet on acceleration and deceleration. Last summer I pulled the drive shaft out thinking it was the nut backed off but it was fine. I got to the part where I couldn't take it apart any more so I took it to the local Yamaha Stealership. They replaced the bearings, charged me like $400+ and I put it back in with no change. So I figured maybe it was just quiet and it's normal shaft noise. But tonight I finally came to the realization I think it's not right. It's like the crown and pinion aren't lashed right. Looking for some advice.

 

[MaxMidnight]

The less wind noise you have the more mechanical noise you will hear.
I usually ride with ear plugs and when I occasionally don't the noises coming from the motor and transmission are quite alarming but probably normal.

What would be considered normal final drive noise is difficult to say.

You don't say which bearing your dealer replaced but if it was those in the final drive then I would have expected that part of the re-assembly would be to check the lash and shim accordingly?

'Fraid the only way you are going to establish if the lash is incorrect is to measure it.

 

[COP RUNNER]

I have a 2006 , I bought new in 2007 , right off the showroom floor , it is a noisy , old school , mechanical BEAST ! It is by FAR , the noisiest ( ENGINE NOISE ) motorcycle I have ever owned ! If I ride with no helmet on I'm SCARED to lay into the throttle , and if I do my brain keeps telling me to JUMP OFF ! LOL LOL LOL

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[davesax36]

Could be valves and middle gear whine mixed together. You'd really notice it with a big fairing and stock pipes.

 

[Justa6MB]

I'm pretty sure it isn't engine noise as it's not rpm related whatsoever. 4th and 5th gears are when it's most noticeable - between 80-90 kms / 50 mph ish. They said they replaced the bearings in the final drive. But the middle gear could be the culprit? I read one thread where a guy held a screwdriver to his ear and checked front and rear... Could try that I suppose? I did tear the final drive apart to the point where I needed a special tool. But how difficult is it to check the rear gear lash?

 

[davesax36]

Can you make a video of it? Is it noticeable at idle?

 

[MaxMidnight]

...how difficult is it to check the rear gear lash?

The service manual explains the process....only you can decide if it is difficult.

 

[Justa6MB]

No it is definitely drive line related. But I haven't tried putting it up on the stand and running it up to speed to see if I can tell where it's coming from. Perhaps the screwdriver trick or stethoscope. I'll check the manual for verifying the lash. I had a guy set the lash wrong on a 10 bolt GM rear end decades ago and it reminds me of that.

 

[42Below]

The situation where you hear it does lend itself to the lash being wrong.
On light throttle it can float between the front and back face of the teeth where as on accel/decel its hard against one side.

 

[Justa6MB]

Yeah I did the screw driver stethoscope trick and it's definitely coming from the rear. I'm sure they've got the lash wrong. I'm going to start there. Thanks for the feedback.