Brand new Model D makes rattle/scrape sound from flywheel.

[Ground Loop]

Hi all. I received my new Model D/PM4 rower and
assembled it on Tuesday. While the assembly went smoothly, it seems
the flywheel is making an unusual amount of noise when rowing.

I can not tell precisely what is making the noise, but it seems that
the flat back surface or rim of the flywheel is rubbing against the
housing at some point in the rotation. This causes a tapping or
chuffing sound while rowing, like a playing card in a bicycle wheel.

I was able to compare this to another new Model D belong to a friend,
and his machine makes only the normal wind and chain noises. It is
much quieter.

I removed the flywheel cover and checked for any loose packing
material or objects. The inside seems clean, and the assembly is
fine. When I watch the fan spin, it seems like it might be "out of
round" or perhaps imbalanced. There is some vibration, but maybe this
is normal. The machine makes the same noise without the fan cover in
place at all.

The rower functions fine, with a range of drag factor from 85(1) to
200(10) possible, but this rattling noise is bothering other people in
the house when I use it at night.

What can I do to track it down? Should I remove the fan from the axle
and check for wear spots and high points on the backside? What can be
done to make the wheel more balanced and smooth in its rotation? Are
there any spacers available to put more room between the flywheel and
the housing backside?

Update: I downloaded the "Flywheel replacement" PDF file from Concept2, and removed the flywheel. I don't see anything unusual behind it, like wear spots or abrasion. Everything looks fine back there. Now I'm not so sure the noise is coming from the flywheel itself, but perhaps somewhere else along the shaft. It rattles faster when spinning faster, and the rattle is louder than the fan.

I emailed C2 yesterday, but no tips yet. I'm still well within my 30-day return policy, but shipping it back would suck.

Not happy.

[PaulS]

Give C2 a call, cordless phone if possible and walk through some diagnostic things with them, I have no doubt that they will either find the problem and provide a solution.

It's sounds like there may be a loose balancing clip to me, but that would be pretty obvious on inspection of the flywheel and fan.

[Ground Loop]

I got a helpful reply from Concept2, but have yet to isolate the source of the noise.

I got underneath the rower and removed the thin plastic cover over the shock cord. The sound isn't coming from that side of the contraption. Indeed, there's nothing moving or spinning on that side when the chain is at rest, and this sound is directly related to wheel speed.

So I have to come back to something rubbing/tapping on the flywheel at certain speeds.

The balancing clips look okay. The magnet ring is securely mounted. The circuit board is fixed in place.

I'm wondering if the whole wheel is so out of balance that it just gets itself into a wobble at speed and starts rubbing random things. Hard to tell.

I wish I had not discarded the box.

[fastfreddie21]

I recently noticed a similar "Rubbing" sound when my flywheel starts to slow. My model D w/ PM3 only has 90,000 meters.. I noticed when I pull the top of the flywheel away from the erg the sound disappears... I can't figure it out..

Anyone else have similar??

FF

[Ground Loop]

I just wanted to post a wrap-up to this thread and report that my problem has been completely solved.

Even with helpful pointers and instructions from C2 support, I wasn't able to diagnose the cause of the noise myself. So, Concept2 replaced the entire wheel section under RMA, and fast!

My rower is now as smooth and quiet as the wind. My entire household thanks C2 for the rapid turnaround on this fix!