Brand new SkiErg..clunk noise on double/single poling

[Citroen]

Have you reported this to Concept2? Write an email to info@concept2.com.

[Keef]

First off: You are very fit Sir with pulling that numbers at 65yo/78kg!

Thank you very much for the investigation work and reporting it here, great help. I‘m a bit scared to disassemble a brandnew machine and also i find it a bit disappointing. i have to think about whether or not i disassemble or get in contact with them for a new one. And if they send a new one who says it doesn’t have the same issue again. At least enough time available atm with the lockdown.

You can upload photos to an external host and copy the link in here if you don’t mind.

Cheers!

here should the clips of the bearing seat issue
https://www.youtube.com/watch?v=X7JuIJta3vo

[Keef]

The clunk is definitely the result of the two bearings (PN1315), front and rear moving within their metal chassis cups.

The 12mm bearings (PN1315) are first mounted in a hard 'neoprene' cup (PN1013), this in turn is then mounted in the metal cups welded to the chassis front and rear.

To prevent this movement I made two packing bands of 1mm hard rubber, 8mm wide with a length of the circumference of the neoprene bearing cup. These are placed inside the metal chassis cup and the bearing and cup pushed hard into it. Result no movement of the bearing.

Well done on the great detective work and results! I wonder if that's the same issue with mine.
Has the movement become any easier and/or faster? What did you use for the 1mm hard rubber strips?
Skierg2 schematic

This season I began with the SkiErg in the local gym. Total season 1,161,183m, did not feel any movement on that erg.

If you haven't done so, you can add all of those meters to your log.

here should the clips of the bearing seat issue
https://www.youtube.com/watch?v=X7JuIJta3vo

[Concept3]

Great Video Keef, very helpful again and sorry for my late response. Today i dismantled the frontside of the flywheelcover and there it is. I have only a loose frontside bearing and not so extrem like on yours, but it’s loose. Backside bearing is tight. Turn volume up to hear the clunk-sound:

https://m.youtube.com/watch?feature=you ... Nv5ckOD0PE

I copied this quote from the other thread:

No clunk noise with mine — pretty quiet. I can use it and have the tv on in the background and hear it with no problem.

FYI replacement on its way. hope this one is 'tight'

Your fix with the butylstrip would last forever i think but i will get mine replaced to. I really hope the next ones don’t have it. I will get in contact with them tomorrow.

@Citroen: Can you please change my username to „NoWatts“. Thank you.

[Citroen]

@Citroen: Can you please change my username to „NoWatts“. Thank you.

Can't be done, sorry.

[johnlvs2run]

Today i dismantled the frontside of the flywheelcover and there it is. I have only a loose frontside bearing and not so extreme like on yours, but it’s loose. Backside bearing is tight. Turn volume up to hear the clunk-sound:

https://m.youtube.com/watch?feature=you ... Nv5ckOD0PE

C3, thank you for doing the video. I wonder if that's the same issue with mine, and will check when I get a chance.

[Keef]

Today i dismantled the frontside of the flywheelcover and there it is. I have only a loose frontside bearing and not so extreme like on yours, but it’s loose. Backside bearing is tight. Turn volume up to hear the clunk-sound:

https://m.youtube.com/watch?feature=you ... Nv5ckOD0PE

C3, thank you for doing the video. I wonder if that's the same issue with mine, and will check when I get a chance.

You're welcome...kind of good to see there is a bit of slack on yours. Thought maybe I was getting a bit picky.
Anyhoo, Up to about 180k m / 150-320w sessions since the (non destructive) modification on the 15th March. All holding out it seems...and hanging on to 'my' SkiErg.

C2 Uk were great and insisted on a replacement. Unfortunately had to reject it as the replacement was not in good shape. Hey ho...
part no. 2147 Front frame panel
The upper section was deformed.
Part No. 2012 Frame Cap rear screw
Screw has been pulled from plastic body of frame cap.
Part No. 1923 Perforated Fan Sheet
This has been incorrectly fitted. Over tightened before the fitting of the fan cover.
I believe the bend had been formed by a large turning force directed to the front of the machine. One of two poss scenarios.
A fully assembled machine has been operated with the optional floor stand.
With both left and right arms PN 2173/2174 attached to the front frame panel PN 2147 by only the front four bolts and the rear four bolts not installed.
or
If the complete upper pulley assembly PN2734 and PN 2176 etc was still atached to the upper part of the left and right arms PN 2173/217, with the unit on its back, this would certainly produce the amount of leverage required to bend the front panel at that point.

[NoWatts]

Hi there, it‘s me Concept3. I changed my username.

I contacted C2 Switzerland on April 14th and told them the „problem“ and sent them the link to my videos. They were very friendly and helpful and said that a little bit of movement of the bearings is normal but on my machine it seems to be too much. They made me the offer to either change the whole erg or just to send me the spare parts PN1315 and PN1013. I choose the sparepart option because I thought it is less of a struggle than dismantling and packing the erg to send it back and install a new one that may have the same „issue“.

Today I received the parts, three weeks later. They had to ship it first from the central warehouse in the Netherlands to Switzerland and than to me to Austria. And with the Covid19 stuff it needed that long. However, I have a rower too and bicycles and I used it also with the clunknoise. No problem.

As soon as I had the parts in my hands I started to install them. And guess what, the new parts doesn’t differ from the previous installed ones .

I feared that this would happen and I guess it’s maybe with all skiergs the same and the majority just don’t care about it. For me it felt like there’s something wrong, you could feel and hear the upward/downward play of the axis.

So I did the same fix like Keef has done. I cut a small strip of an old bicycle innertube, wrapped it around the rubber cup, put an slight amount of grease on it and put everything together again. I did this also with the rear bearing as it was also loose.

Result: Clunk noise is gone! And it will last forever . I am okay with this solution and will keep it like that.

https://youtu.be/jxqDFBxGeVQ

Cheers!

[Citroen]

You should give the details of that inner tube hack you've done to fix this back to Concept2. They may have a design issue.

[johnlvs2run]

Keef and NoWatts, have you noticed a difference in performance and smoothness with the modification?

[NoWatts]

Keef and NoWatts, have you noticed a difference in performance and smoothness with the modification?

The feeling on the handles is a tiny little bit more direct, the slack from lifting the axis the 1-2mm before the spools catch it is gone. So is the clunknoise gone. I also had a harmless vibration noise before, that was only noticeable 1-2 seconds at a certain RPM, when the flywheel was decelerating to deadstop, short before deadstop. This is gone also. Dragfactor range is the same like before with 52 to 164 with frontplate installed. Average Watt on a steady 30 minutes piece has increased from 120W to 120,01W .

Is the loose bearing issue a designflaw? Honestly idk, but why should it be necessary to give the axis 1-2mm play and produce a clunknoise? Makes no sense.

[Keef]

Keef and NoWatts, have you noticed a difference in performance and smoothness with the modification?

The feeling on the handles is a tiny little bit more direct, the slack from lifting the axis the 1-2mm before the spools catch it is gone. So is the clunknoise gone. I also had a harmless vibration noise before, that was only noticeable 1-2 seconds at a certain RPM, when the flywheel was decelerating to deadstop, short before deadstop. This is gone also. Dragfactor range is the same like before with 52 to 164 with frontplate installed. Average Watt on a steady 30 minutes piece has increased from 120W to 120,01W .

Is the loose bearing issue a designflaw? Honestly idk, but why should it be necessary to give the axis 1-2mm play and produce a clunknoise? Makes no sense.

'Design fault'...hmmm I have used those very words myself. Maybe they have been a little lax in the initial design R&D. If I was given the task of bearing shaft design I would have used already tried and tested CoTs ( commercial of the shelf ) parts. One assembly that springs to mind from years of biking experience...the Shimano HollowTech bottom bracket , check out the online fix / fit videos. I have fitted quite few and it doesn't take long to realise this would be the perfect solution.

[NoWatts]

Hello Keef!

Have you got an new erg now? I’m just curious because so much people bought an skierg in the lockdown but no one complains about clunknoise.

[johnlvs2run]

I took the fan cage off, and the back bearing was okay, but the front one came off with the axle. The bearing
attachment was loose in the socket, but not enough to fit the innertube so I tried plastic electrical tape. This didn't
work very well, as it scrunched up and the bearing kept coming back out, especially when reattaching the fan assembly.

I put the fan back on anyway, and pushed it against the bearing a few times, which apparently worked.
Now, for the first time since getting the Skierg nearly two years ago, the thunk-thunk is gone!
Woo hoo! Thanks for posting all the helpful comments and suggestions.

[Woobles]

I just got my Skiierg yesterday after being on the waitlist for a few months..

I’m also getting this double thumping noise on my brand new machine. I would have thought they would have resolved this by now

Is there any correlation between the ‘Skiierg’ label/sticker on the machines? I notice one has a snowflake on the logo and the other doesn’t.

My machine doesn’t have that snowflake logo. Is the snowflake logo on newer machines and I’ve got an older model?

The reason I ask is because I have an issue with the PM5 screen as well and wonder if this is a faulty unit returned by another customer.