Can anyone identify muffler sound?

mukaiboston · Post by **mukaiboston** » Sun Jun 17, 2018 10:38 pm

Just curious...

https://www.dropbox.com/s/lnbq1muut2uu5 ... 3.MOV?dl=0

I first thought something was loose. Checked all the screws and can't find anything. That rattling sound on deceleration appears to be coming from the exhaust hole where the air leaves. We didn't test the pipe with soap and water, but the sound is not coming from the pipe or the end where it attaches to the engine. It still accelerates great and mileage is normal, although sometimes when starting the engine light will come on and then the RPMs drop and acceleration hesitates when giving throttle. Next time this happens, I will make a video, but an ECU reset seems to cure this issue until the next time it happens. I assume it's the fluctuating heat and humidity but, if there is a problem with the muffler, it could be that as well.

I think what I'm going to do is order a replacement exhaust since it takes Scooter Lounge like two weeks to get Buddy parts. If anyone of you have seen my previous posts, I've had ongoing issues with exhaust noises, check engine light coming on and my rear brake assembly vibrating and locking up the wheel (got those parts finally by the way). I think it makes sense to now just replace all of this before something really fails and the scooter isn't useable.

wheelbender6 · Post by **wheelbender6** » Mon Jun 18, 2018 1:18 am

I have never heard an exhaust like that, where the funny noise occurs during decel.
-Have you tried wrapping some wire around the pipe at the heat shield to see if a loose heat shield could be the problem?
-Shot in the dark, but did you take a look at the plug to see if it is running lean?
-I'm really cheap at times, so I would try a few small things like that before ordering more parts.

babblefish · Post by **babblefish** » Mon Jun 18, 2018 1:37 am

I dunno, it just sounds like exhaust gas resonance as it flows through the various baffles in the muffler. I've heard similar sounds coming from motorcycles. I personally wouldn't be too concerned about it.

k1dude · Post by **k1dude** » Mon Jun 18, 2018 4:04 am

Are you sure it isn't your license plate frame? It sounds like it's coming from the pipe, but it's often the plate vibrating against any aftermarket frame you might be using.

mukaiboston · Post by **mukaiboston** » Mon Jun 18, 2018 1:56 pm

Thanks. I will check again but I grabbed the muffler and really shook it. I could not make it move. Checked all the screws too. Nothing appears to be loose.

I can check the spark plug again but I replaced in December and I replace them every year.

sc00ter · Post by **sc00ter** » Mon Jun 18, 2018 3:25 pm

My speakers must be bad as it sounded normal to me. Now, if you think you hear a "sound" thats not normal, and everything seems correct, the inner baffle could be broken loose on the inside of the exhaust. My Burgman 200 had it happen. Keep in mind that exhaust systems generally have 5 year warranties.

Stanza · Post by **Stanza** » Mon Jun 18, 2018 5:40 pm

Could just be a loose baffle in the muffler. Try tightening the three screws holding on the chrome end cap on the muffler.

350kmi · Post by **350kmi** » Tue Jun 19, 2018 1:32 pm

My 170 used to make a similar sound. It always ran fine with the noise and I was never able to isolate the sound other than it seemed to be coming from the exhaust. It could be an early sign of a loose baffle - I first noticed the sound around ~5000 miles, at around 10,000 miles on my original muffler a baffle had come fully free inside the muffler. After the baffle was loose I didn't notice the original sound anymore, just the 'metal ball bearings bouncing around a tin can' sound of the loose baffle in the muffler. Once the baffle was fully loose I did have noticeable problems as it would occasionally move in such a way to restricted exhaust flow which would cause noticeable slowing of acceleration and about a 10 MPH drop in top speed. If I pulled over and tapped the exhaust smartly a few times it would go back to running fine until the next big bump.

After a few of these slowing incidents I decided to replace to original exhaust with NCY unit. Unfortunate the NCY muffler only lasted about 13,000 miles before its single internal baffle broke loose. I don't notice any restriction/running problems with the broken NCY, so I rode it like that until the loose part eventually worn a hole through the bottom of the muffler which made it quite loud. I found a slightly used OEM muffler off a 2014 Buddy 170 which has been on the scoot for the last 4500 miles - so far so good. My 170i is a 2012 and I am hoping perhaps the muffler designed was improved by 2014, but time will tell.

On a side note, my 2007 Buddy 125 has had no exhaust problems in 19,000 miles. If my current OEM 170 exhaust also fails I think I might try the 125 exhaust on the 170 just to see if the is any noticeable performance loss.