Modern Vespa

Hi, I was wondering if anyone could shed some light on an issue I have with my X10 350.
The bike has identical engine/wet clutch/final drive to the Beverly 350.

I've started getting a creaking noise from the rear hub, I can only hear it at low speed, that's not to say its not doing it all the time. The bike has done 10,200 miles and is over 10 years old, so I guessed a belt change would cure this.
I've changed the belt, fitted new rollers and guides and to the variator and changed the hub oil following the infamous Robot on YouTube, but still the noise remains. The noise is there if I slow the bike down enough for the clutch to disengage, kill the engine so the bike is rolling under inertia, so that then the belt and variator are not turning so cant be a belt problem. It will make the noise even if i just push the bike forward and backwards with the engine off, so I'm guessing that its coming from the clutch/final drive side?
There is no disenable movement up and down of the rear wheel..

Any help greatly appreciated

One of the rear bearings, perhaps?

I replaced my Scarabeo's rear swingarm bearing after it made a creaking/groaning/popping sound for a few hundred miles. (13 years old/21k miles at the time, lots of outdoor storage by a PO). I thought it was the TPMS sensor loose in the tire for a while (nope). It's an interesting DIY job if you have or are willing to buy or borrow the tools.

So it is technically a BV350 (what I think is really a top scooter).

You changed the belt and the rollers but no result.

I see this here on the forum so often. People hear or experience something unusual and start changing parts without checking where the problem comes from.

Your reasoning is sound but the exercise you did after changing belt and rollers you had better done that beforehand, because that exercise clearly proved the noise is not coming from there.

It is only a tip that in many cases easy and cheap checks can give you a much better idea where the problem has to be found.

In your case you state it is in the final gear because that is where you hear the noise coming from with engine and transmission off.

Your scooter may be 10 years old but did only 10k miles, meaning it is next to brand new. Even if it never had any maintenance it should still be OK.

You changed the oil in the rear hub. I guess it was not running dry?

Would it be possible to make a recording of the noise that you hear?

Seems to me that after 10k miles, replacing belt/rollers/guides/gear oil is simply good old routine maintenance - especially if the scooter is new to him. No harm done, probably needed to be done anyway, but it didn't address the issue. So, next diagnostic step, whatever that is.

Will it make the noise if you spin the rear wheel by hand?

This was how my situation presented. Note the first few seconds are a snap/pop when turned by hand. The sound once the engine is running is difficult to hear in the recording, so I annotated it in text above the video.

Thanks for the reply's guys
I've managed to record the sound that its making.


https://www.youtube.com/watch?v=yRbX00R_0dc

https://www.youtube.com/watch?v=2xCsIzeYPgM

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Hard to know with certainty from the video but it certainly sounds like metal scraping on metal. It sounds like drum brakes getting hung up in the hub - but that scooter doesn't have drum brakes. Nevertheless I would rule out brake caliper, pad, and disc issues since they are reasonably accessible. Assuming those are satisfactory I would then be very methodical about figuring out where the sound is coming from, using a stethoscope or long tube to the ear.

A grungy bearing is still very high on my list of likely suspects. There are lots of ways water could have intruded into a "sealed" bearing and wrought havoc over 10 years. Again, does the noise appear when spinning the wheel by hand with the scooter up on the center stand?

I had an idea inspired by your questioning of a worn bearing, so I removed the right hand side wheel suspension arm that houses a bearing that the rear wheel rotates in. Maybe this bearing was worn and was the cause of the creaking sound....

While dismantling the rear wheel, when it came to removing the rear wheel retaining bolt, I removed the cotter-pin and cover, only to find the wheel nut was only hand tight! DOH! I must have overlooked torqueing this important nut when I replaced the rear tyre a few thousand miles ago.

I went ahead and removed the wheel side support, to find the bearing in great condition. I've put it all back together, putting a little grease on all the bolts and the wheel hub to aid removal in the future, and this time I torqued the rear wheel nut to 120nm.
All back together now and the creaking has vanished!!!!

Thanks to all that gave me some ideas, especially to Juan_ORhea

Glad to hear it! Do not be shocked if one of the rear bearings still ends up failing. The slop associated with a loose fastener like that can set the wheels in motion, so to speak, for damage that manifests itself later.

Isn't this what people used to call "Seal farts?"
Had it for 7 or 8 thousand miles and have been told not to worry about it.....so I don't.