Fellow AK550 Owners Question - Noticeable vibration at deceleration

[mousejunks]

On mine, this happens right when the tachometer drops off the 3000 bar...just a slight little "thump"

Its driving me neutz

I get a brief thump on deceleration at 2000rpm on my Downtown 350i. I don't notice it anymore and don't care after seeing no damage or wear on the transmission after 20,000km.

[Stig / Major Tom]

Assuming something is at fault to cause that thump on decel of this big heavy scooter...what could one imagine it to be?
I'm no expert, but I seriously doubt that there is anything at fault causing this sensation on your scooter. I suspect that a tear-down would reveal that nothing is out of spec.
What does your dealer say?
Stig

[jermwars]

Hi AK550 Owners.

I have about 700 miles on my AK550. From the beginning I noticed a vibration, may more of clunk during deceleration at about 20-22 mph (32-35 kph).

My guess is it's the clutch/transmission disengaging or something like that. The scooter runs fine, without any noticeable issues.

Changed the oil and filter about 100 miles ago and no change and runs great.


Have any other AK owners noticed this characteristic?

You get any ideas on this issue yet?

Been waiting to hear back from you

[jermwars]

I get a brief thump on deceleration at 2000rpm on my Downtown 350i. I don't notice it anymore and don't care after seeing no damage or wear on the transmission after 20,000km.

Thats comforting.

Im sure im just being hyper-anal since this is the first brand new vehicle ive ever bought

Id hate to ignore a developing problem until the warranty wears out and it becomes critical

[jermwars]

Assuming something is at fault to cause that thump on decel of this big heavy scooter...what could one imagine it to be?
I'm no expert, but I seriously doubt that there is anything at fault causing this sensation on your scooter. I suspect that a tear-down would reveal that nothing is out of spec.
What does your dealer say?
Stig

My first instinct was that its the clutch popping open...but if so, it would occur on all the AK550s and probably any other similarly designed clutch...I dont get it on my yamaha majesty 400, but thats a different configuration as you probably know.

Ive never dug into a setup like this one so im just not very confident in diagnosing

The guys in the service department pretty much dismissed it when i first described it to them but after bringing it up again they said i can drop it off and they'll look at it.

[Neil955i]

The guys in the service department pretty much dismissed it when i first described it to them but after bringing it up again they said i can drop it off and they'll look at it.

Interestingly pretty much the same response I got to my noisy take-off on my new XTown 300...  Until the transmission failed completely some 500 miles later!  Turns out a variator nut hadn't been correctly torqued up at the factory    The good news is it was sorted quickly under warranty and there have been no further issues.

[jermwars]

Hi AK550 Owners.

I have about 700 miles on my AK550. From the beginning I noticed a vibration, may more of clunk during deceleration at about 20-22 mph (32-35 kph).

My guess is it's the clutch/transmission disengaging or something like that. The scooter runs fine, without any noticeable issues.

Changed the oil and filter about 100 miles ago and no change and runs great.


Have any other AK owners noticed this characteristic?

Wel?

Did you find anything out?

Are you still having the problem?

[Neil955i]

Wel?

Did you find anything out?

Are you still having the problem?

Yep, we're all on tenterhooks!

[jermwars]

Yep, we're all on tenterhooks!

I need CLOSURE!!

[jermwars]

Good to know there are a few ak 550 owners out there.  I don't think this bike was introduced in the US until 2021 (could be wrong), anyway I bought an ak550 3 weeks ago from a dealer in Phoenix, az.  It was the company's demo and had 438 miles on lit.  I was always reluctant to buy a demo "cuz it could have been ridden hard in the 1st couple of hundred miles.  This one though was in perfect condition with absolutely no problems. I'm very happy since I have had many scooters in my life but not one with the power of a motorcycle.

To address the problem you brought up.  I find that I get intermittent vibration (thru the foot board) when I not putting the engine under load such as when I'm going 56-60 on level ground while backing off the throttle a bit and not losing speed. Otherwise I don't get the feeling.  I have a Piaggio BV 500 also and find that that happens to it as well but not as noticeable. I suspect this will go away with more bread-in time. 
WEL, thanks for starting a conversation.

Does your belt sit all the way to the left in the wheel sprocket? Mine is almost touching the little wall enclosing the left side...i feel like it should be more centered

[rjs987]

Does your belt sit all the way to the left in the wheel sprocket? Mine is almost touching the little wall enclosing the left side...i feel like it should be more centered

I've noticed that on a few AK scooters I've looked. The one I test rode in Fort Smith and also one who's owner posted pics on the ADV Rider forum. Both were much closer to the left side of the rear sprocket than the right side. I mentioned on that other forum that the service manual indicates that there should be a space of more than 1 mm on either side of the belt to the sides of the sprocket. That actually means one side can be close and the other will have much more space showing. As long as it doesn't wander side to side. It doesn't really need to be centered unless you are just "that way" about things. 

[jermwars]

I've noticed that on a few AK scooters I've looked. The one I test rode in Fort Smith and also one who's owner posted pics on the ADV Rider forum. Both were much closer to the left side of the rear sprocket than the right side. I mentioned on that other forum that the service manual indicates that there should be a space of more than 1 mm on either side of the belt to the sides of the sprocket. That actually means one side can be close and the other will have much more space showing. As long as it doesn't wander side to side. It doesn't really need to be centered unless you are just "that way" about things. 

Thanks for the reply! Much appreciate it.

I didnt really realize i was "that way" about things until i got this new bike...Gonna need to work on that a little

[jermwars]

Dealer service center checked it out and said its nothing to worry about...just the clutch releasing.

Im still skeptical.

[rjs987]

Thanks for the reply! Much appreciate it.

I didnt really realize i was "that way" about things until i got this new bike...Gonna need to work on that a little

No worries.
It's a new machine for you. I'm exactly "that way" about my new machine even if it is a used machine but just new to me so I am VERY familiar with that. 

[Stig / Major Tom]

Thats comforting.

Im sure im just being hyper-anal since this is the first brand new vehicle ive ever bought

Id hate to ignore a developing problem until the warranty wears out and it becomes critical

If it is like other Kymco scooters - relax- you have 2 years on the drive-train warranty.

Stig