Concept2 Forum

I have a new Model D, and I noticed a mechanical clunk, right when transitioning from drive to recovery. Is this normal operational noise? Otherwise, is it a basic fix?

https://youtu.be/8M78vjyXLmo

Thank you,
Arpat

Hi Arpat, and welcome to the forum.

No, that clunk / thud noise isn't normal.

Have you been able to identify where it's coming from? I'm guessing that it's either from the fan / axle bearings / clutch area or from the seat. I've never had that problem, either with my Model C at home or the E I use at the gym, so I can't help much, but I can speculate...

If the source is the fan area then I'm guessing you're in trouble. If it's from the seat, then it probably isn't too hard to fix yourself if it's a mechanical issue, or it could be due to user error / bad technique.

Edit: I just thought of another potential source of the noise (although not likely) - it could be somehow related to the bungee / traveling pulley.

Good luck tracking down the cause.

Thank you for the feedback, Ombrax. As you suspected, the issue was the pulley system (rather than the seat or the clutch) and very easy to solve.

The plastic cover under the frame was not seated well. It was sitting ~1cm high, on top of the small guide screws. The chain in operation wasn't touching the plastic cover, but the moving pulley mechanism was hitting the raised plastic cover at the end of each drive. That's where the clunking noise was coming from. Seating the plastic cover properly solved the issue.

I'm glad it was an easy fix. : )

arpatoz wrote: ↑

February 27th, 2021, 8:54 am

Thank you for the feedback, Ombrax. As you suspected, the issue was the pulley system (rather than the seat or the clutch) and very easy to solve.

The plastic cover under the frame was not seated well. It was sitting ~1cm high, on top of the small guide screws. The chain in operation wasn't touching the plastic cover, but the moving pulley mechanism was hitting the raised plastic cover at the end of each drive. That's where the clunking noise was coming from. Seating the plastic cover properly solved the issue.

Had a similar issue recently. Thought something in the chain or gear was 'catching' for a single chain link when beginning the recovery. Of course in the process of deciding to clean and re-oil my chain, I had shifted the plastic cover during this process and returned to a smooth chain experience.

Now I'm thinking that my issue was the plastic cover as well, and not some lubrication problems.

Those “guide screws” in the flanges of the hollow beam are threaded rivnuts that receive the machine screws that bolt up the leg struts at assembly. It is a 5’ job with a rattail file relieving the acrylic drip shield/sound deadener to clear the rivnuts and seat on the flanges. Or rattle the shield until it drops, which, if memory serves, also takes a couple minutes. Life do get tedious dont it?