Why would semi-solid fork make whizzing sound? Alert the semi-solid fork is probably not the right terminology, it shows that I don't know 100% whether the work has some sort of inner suspension.

My bike is almost this one but I feel there is some sort of inner suspension thing because there is a rubber or it is just decorative and I just imagine it is suspension due to tires. There is a small rubber cork to the fork so I think it is to oil the suspension. I looked inside the rubber thing and there is suspension looking metallic thing. Notice the small rubber cork for the oil, I have never put anything there.



I haven't yet dissasembled the bike and no specific specs because I bought it as 10k-driven used bike. So no precise diagnosis yet.

Description of the sound

The front makes a lot of whiizing sound. When I drive with weight on the front, the sound disappears. When I slow down even a little (i.e. the force is less on the front due to de-accelerating), the sound emerges again. Because of this observation, I thought that the fork is not rigid-fork but with small suspension. What would you suggest to do with the fork? I will disassembly it and apply some sort of special lubrication (it may be just that lubrication is eroded) or will I do something else?
From looking at the picture, you do have a front suspension, of a type you would usually see on "hybrid"/"comfort" bikes, with a very small amount of travel. I can't think of any way that a problem inside that suspension component could cause a whizzing noise, though.

I think it's more likely the wheel rubbing against something, such as a fender, brake pad, etc.  If the wheel is off true (not straight) or not seated properly on the fork, it could be slightly rubbing against something but get better with some weight on it.

What's on the front of the bike that gets anywhere near the wheel? Front brakes? Fenders? A basket or rack? Lights? Disk brakes like shown on that bike?

Here's some things I'd try:


Does it make the noise with no weight on it?  Can you hold up the front of the bike and listen? Figuring out exactly where the noise is coming from would be very helpful.
If you hold the handlebars or fork steady and try to move the wheel sideways, is there any play (does it wiggle or is it solid)? The wheel should spin freely
Look at one of the brake pads (or something else that's close to the wheel) and spin it; can you see the wheel move side to side as it spins?
Wiggle the spokes. Do they all feel the same, or do some feel looser than others?
If there's anything optional, like fenders and you still haven't found the source of the noise, try removing those and see if the noise goes away.