Whine when throttle open about 1/8

Having trouble? Need more info on something mechanical? Ask here!

Moderator: Modsquad

op3l
Regular User
Regular User
Posts: 79
Joined: Wed Feb 05, 2020 8:34 pm
Year: 2019
Color: Black
Location: Vietnam

Whine when throttle open about 1/8

Post by op3l »

My 2018 pcx recently developed a whine that's pretty easy to hear when throttle is open about 1/8 to about 1/6. The whine persists even when speeds go higher but throttle position don't change while it accelerates. If I let go of throttle, the whine slowly disappears while speed slows down

The only thing I had done on the bike was to get an air filter change, but it was at some road side place and the guy guaranteed me it's genuine OEM parts(ya right)

Any ideas what is causing this whine? It's very loud and easily hear over the sound of the engine and exhaust.
op3l
Regular User
Regular User
Posts: 79
Joined: Wed Feb 05, 2020 8:34 pm
Year: 2019
Color: Black
Location: Vietnam

Re: Whine when throttle open about 1/8

Post by op3l »

Don't know how to edit post on mobile so replying to own.

The problem didn't start right away after filter was replaced. It started just today after about 2 months of riding.

It sounds a bit like super charger whine except at higher engine speeds and more open throttle the sound disappears.
mymitzi
Regular User
Regular User
Posts: 267
Joined: Mon Mar 04, 2019 6:05 am
Year: 2013
Color: black
Location: Delaware

Re: Whine when throttle open about 1/8

Post by mymitzi »

The fact that the whine disappears at higher RPM's is good thing. My PCX has a whine that correlates to 25-30 mph. It's been that way for ages.
Not sure ours have the same causes or not?? Never have been able to figure what causes mine but @ 69 K , not worried about it.
User avatar
Conelite
Regular User
Regular User
Posts: 313
Joined: Sun Jan 21, 2018 11:53 am
Year: 2017
Color: Blue

Re: Whine when throttle open about 1/8

Post by Conelite »

Could just be an air leak or something.

Always go WOT lol. Or add an exhaust and you wont be able to hear it.
2017 PCX 150
Wirus Win Exhaust
Steady Garage Intake
Z-Bars
NCY Variator
mymitzi
Regular User
Regular User
Posts: 267
Joined: Mon Mar 04, 2019 6:05 am
Year: 2013
Color: black
Location: Delaware

Re: Whine when throttle open about 1/8

Post by mymitzi »

I've had many motorcycles over the years and most of them had an "unsweet" spot somewhere in the RPM range. 1 , 2, or 4cyl included.
Even the GoldWing [1980] Comparatively slight and hardly noticeable on the road. Maybe the 6 cyl are smooth throughout the range.
User avatar
you you
What's a wot?
What's a wot?
Posts: 10000
Joined: Sat Jun 30, 2012 5:37 pm
Location: Between Lulu and Chichi

Re: Whine when throttle open about 1/8

Post by you you »

Conelite wrote: Tue Sep 21, 2021 12:38 pm Could just be an air leak or something.

Always go WOT lol. Or add an exhaust and you wont be able to hear it.
This is good advice. In a car you would just turn the radio up...
Post Reply