Loud frame "TOCK!" sound on alloy eMTB — can't isolate the source

Looking for ideas from anyone who's chased a similar issue...

• 2025 ARI Wire Peak 2.0 (Large)
• Shimano EP8 drive unit
• RockShox Super Deluxe Ultimate (210x55)
• Bike is <1 year old

The bike developed a loud, distinct "TOCK!" after several months of riding. It's not squeak—it's a knock.

It happens mostly while seated, climbing, and riding moderately rough terrain, but not exclusively. It doesn't require a big hit or bottom-out.

History:

• Original DVO Opal failed twice (air can seal blew out within weeks each time).
• ARI replaced it with a Super Deluxe Ultimate.
• The noise only appeared months later with the RockShox.

Current suspects:

• Shock mounting hardware / DU bushings
• Pivot bearings
• Shock internals
• Dropper/saddle
• Motor mounts

I also have another Wire Peak with a Fox Float, so I can swap shocks to see whether the noise follows the shock or stays with the frame.

Has anyone experienced this exact type of knock, and what was the eventual cause? Any ideas?

labdrifter said:

Looking for ideas from anyone who's chased a similar issue...

• 2025 ARI Wire Peak 2.0 (Large)
• Shimano EP8 drive unit
• RockShox Super Deluxe Ultimate (210x55)
• Bike is <1 year old

The bike developed a loud, distinct "TOCK!" after several months of riding. It's not squeak—it's a knock.

It happens mostly while seated, climbing, and riding moderately rough terrain, but not exclusively. It doesn't require a big hit or bottom-out.

History:

• Original DVO Opal failed twice (air can seal blew out within weeks each time).
• ARI replaced it with a Super Deluxe Ultimate.
• The noise only appeared months later with the RockShox.

Current suspects:

• Shock mounting hardware / DU bushings
• Pivot bearings
• Shock internals
• Dropper/saddle
• Motor mounts

I also have another Wire Peak with a Fox Float, so I can swap shocks to see whether the noise follows the shock or stays with the frame.

Has anyone experienced this exact type of knock, and what was the eventual cause? Any ideas?

Click to expand...

Rocker pivot bearing.

Weeksy said:

Rocker pivot bearing.

Click to expand...

I have cleaned and lubed those so many times now.

labdrifter said:

I have cleaned and lubed those so many times now.

Click to expand...

remove and re-install new ones.

Not the Ari Peak, but my Trunnion bearing on my Chromag Darco developed the exact same behavior. I replaced the BB, chainring, and serviced the rear hub and main pivot looking for the sound, and couldn't replicate it on the stand. Turned out the drive side trunnion bearing was sticky. Re-greased it to test and the problem went away, waiting on new bearings to make it "permanent" (another year at least).

Side note; my previous bike was SUPER noisy because it ate bearings like my dog eats kibble. The Chromag has been nearly maintenance free for a year and a half. This was it's first mystery noise. If only they'd make an eeb