Anyone have this clutch noise when downshifting to 2nd?

[Orchardbike]

I drove about 12 miles yesterday and it happened twice, always 3rd to second coming into a low speed corner/junction. Mine’s had a new clutch and new gearbox (after 700 miles). It didn’t do it before, but started around 2 months after the work was completed.

Replying to myself. Today, I drove around 70 miles and it didn’t happen at all.

It doesn’t sound like clutch to me, it’s almost like a flap or vent vibrating/buzzing. It still could be the clutch, I’m just saying how it sounds to me.

 

[GetawayDriving]

Yes thank you. I'll just have the dealer do it while it's under warranty, just to keep records around the clutch behavior.

 

[zoomdaddy]

Can now confirm, the sound presents on mine downshifting 3:2.

 

[Jinba ittai]

Here’s what AI is telling me:

Likely Culprit: Resonance During Torque Reapplication

When you release the clutch during a downshift, the engine and transmission re-engage, and torque flows through the drivetrain. If a component — like a mount, bushing, or even the exhaust — is slightly out of spec or loosely fitted, it can resonate under that brief load spike.

• Transmission or differential mounts might be flexing or vibrating under the sudden torque reapplication.
• Exhaust hangers or heat shields could be resonating due to harmonics in the exhaust flow or vibration.
• Drivetrain backlash (slight play in gears or joints) can cause a brief vibration when torque reverses direction.


It doesn’t sound like a heat shield vibrating to me. Transmission or differential are possible. To my ear that seems more likely than the clutch.

 

[Jinba ittai]

Reading it again I’m leaning towards that last point about the drivetrain backlash. I only hear the sound when engine braking and the torque direction is reversed. Could be play in the gears given that it’s more prominent in first and second gears. I think the other suggested culprits would cause the odd vibration at other times.

Now whether this is a real problem, I don’t know. Hopefully just a strange sound.