Chain Slip? Advice Please!

[c2jonw]

I agree it's probably the clutch, and the best thing to try is as Carl describes- pull the flywheel and get some lightweight oil on the clutch. Colder temperatures will increase the likelihood of the clutch slipping because the lubricant thickens and inhibits the springs which push the rollers to engage on the axle. If your machine is always used in colder temperatures it can help to row at an easy pace to warm the clutch a bit before pulling harder. I'm a little concerned by the popping sound at the release. My experience with slipping clutches is that they either engage or they don't, and there's no noise associated with the slip. So it's also possible that the clutch is bad and you're getting a partial engagement which is letting go at really high and fast catch loads. When you had the flywheel off did you notice if there were any of the rollers missing in the clutch?

[MiddleAgeCRISIS]

Hello,

I was having a crack at some sprints this evening on the slides and seem to have encountered a problem with the chain slipping when I get towards max wattages. I wasn’t having the same problem last week, and the erg seems to row smoothly otherwise.

Could anyone offer any advice as to whether I need to strip the thing down and replace some components?

Here’s a video of one of the slips:
https://youtu.be/LGGwDUZ5BAY

Its 99% certain the Chriss. Needs oil and if its really broken it can be replaced. On the c2 can be found how. Its in the case, so you need that to take off etc..

Thank you - I’ll definitely give it an oil as a first step and go from there.

On an uninformed basis and without the technical know how of the other posters - did the chain whip off the cog? Is the rubber band that holds the chain working effectively?

[chrisscott6300]

Its 99% certain the Chriss. Needs oil and if its really broken it can be replaced. On the c2 can be found how. Its in the case, so you need that to take off etc..

Thank you - I’ll definitely give it an oil as a first step and go from there.

On an uninformed basis and without the technical know how of the other posters - did the chain whip off the cog? Is the rubber band that holds the chain working effectively?

I opened the machine up and everything looked fairly pristine inside. I think it was the clutch not engaging at the high rate on slides, but I've got a feeling that my bungee tension isn't quite what it should be and so the chain simply didn't return fully at rate 60 before starting the next pull.

I've pulled plenty of <1:10 splits using it as a static at around rate 40 and not had any problems since. I think I will leave the slides alone until after the worlds, then see if it happens again in warmer temperatures, and if it does, get it examined by someone who knows the insides of the machine better than I do!

[MiddleAgeCRISIS]

Thank you - I’ll definitely give it an oil as a first step and go from there.

On an uninformed basis and without the technical know how of the other posters - did the chain whip off the cog? Is the rubber band that holds the chain working effectively?

I opened the machine up and everything looked fairly pristine inside. I think it was the clutch not engaging at the high rate on slides, but I've got a feeling that my bungee tension isn't quite what it should be and so the chain simply didn't return fully at rate 60 before starting the next pull.

I've pulled plenty of <1:10 splits using it as a static at around rate 40 and not had any problems since. I think I will leave the slides alone until after the worlds, then see if it happens again in warmer temperatures, and if it does, get it examined by someone who knows the insides of the machine better than I do!

Looking at the video , it looks to me that the chain is slapping around so i wonder if the bungee cord is not doing its job well enough. It seems to me that the rearward movement of the slides and the forward movement of your hands is displacing the chains.

[MiddleAgeCRISIS]

On my rowing stroke i drop my hands at say 45 degrees to under the chain ring. This takes the slack off for me but at a much reduced stroke rate.

[MiddleAgeCRISIS]

Hiya , took a look at your other videos and the chain is really struggling to return. i have no idea of the mechanism inside the erg but I'd ask concept if you can put a stronger bungee cord in.

[MiddleAgeCRISIS]

Sorry, I've just looked at Phil Clapps world record where he rows without slides for 500m. He gets no where near the amount of chain slack that you are getting.

I think logically the return of the machine on the slides and your hand return is doubling up the chain slack. Perhaps it is creating slack from both ends and this is resolving just at the point where you drive.

[Citroen]

I opened the machine up and everything looked fairly pristine inside. I think it was the clutch not engaging at the high rate on slides, but I've got a feeling that my bungee tension isn't quite what it should be and so the chain simply didn't return fully at rate 60 before starting the next pull.

I've pulled plenty of <1:10 splits using it as a static at around rate 40 and not had any problems since. I think I will leave the slides alone until after the worlds, then see if it happens again in warmer temperatures, and if it does, get it examined by someone who knows the insides of the machine better than I do!

viewtopic.php?p=512083#p512083

Assuming it's not the usual grease on the flywheel clutch problem then I'd look at the set-up of the slides and the bungees on the slides. You appear to be heading forwards to front stops and you're catching up with the flywheel (because it hasn't gone forwards on the slides) and that's why the chain goes slack.

https://www.concept2.com/files/pdf/us/s ... nstrux.pdf
https://www.concept2.com/files/pdf/us/s ... cement.pdf

[jackarabit]

Mr. Scott’s 1’ WR on slides isn’t mentioned. We can’t assume that the erg used for the short vid is the WR machine, but the sprint power and rate of which he is capable has to be factored in as producing a rather extraordinary test of the mechanical characteristics of the entire drive train. It’s worth considering that neither a “dead rubber” chain return bungee nor a worn throwout bearing in the flywheel may be expected to react flawlessly to the unusual pulse and loading/unloading of Mr. Scott’s highest possible effort.

[MiddleAgeCRISIS]

Mr. Scott’s 1’ WR on slides isn’t mentioned. We can’t assume that the erg used for the short vid is the WR machine, but the sprint power and rate of which he is capable has to be factored in as producing a rather extraordinary test of the mechanical characteristics of the entire drive train. It’s worth considering that neither a “dead rubber” chain return bungee nor a worn throwout bearing in the flywheel may be expected to react flawlessly to the unusual pulse and loading/unloading of Mr. Scott’s highest possible effort.

I took a look at Mr Scott's other youtube videos and compared them to comparable records. I tried to create the chain whip by punching the handle back. I think there must be some slack or binding in the bungee. Hopefully ots an easy fix.

[chrisscott6300]

Thanks for all your comments guys. I’ve started to notice I’m gradually getting a little more slack in the chain returning at rate 40 using the machine as a static now so I think the bungee has lost a little tension. I think I’ll get someone to look at it soon!

[Ombrax]

returning at rate 40

Now THAT is a high stroke rate. I think the low 30's is the highest I do with any regularity. (when sprinting at the end of a workout)

I'm not surprised that there's some slack in the chain at that rate.

[Carl Watts]

With a decent setup and everything working I can rate at 46spm maximum for a short sprint of 500m, the chain has no problem retracting it simply needs lubrication and a bungee thats only a couple of years old. A 10 year old cord has about half the return force by my estimation from a finger pull test with the rower on its nose when I did 6 of them at a gym with new cords. Pretty easy to compare when you have a brand new cord fitted to one rower and a 10 to 12 year old cord fitted to the rower beside it.

[c2jonw]

If the shock cord looks ok but is not providing adequate return force, there is this: https://www.concept2.com/files/pdf/us/i ... stment.pdf

[shu246]

Kroil. Use sparingly, presuming the clutch has been leading a generally clean life and is not gunked up with grease. Speaking as a copier repair service manager manager in a previous life.

In some places, paper feed rollers which had to roll freely when paper was advanced to next stage, roller bearing one-way drive clutches like that on the C2 inertial wheel were used. We freed those with a few drops of Kroil.

Most clutches in copiers and typewriters (IBM Selectric) then were "spring clutches" - a coil spring wrapped around a bushing on the shaft, the spring tail caught on command by a solenoid to let the coil slip. These were quite different and liked to be lightly greased.

Avoid WD-40. A fine product for its purpose, water dispersant in electrical contacts. The volatiles evaporate and leave the bits varnished together.