Model C slipping Clutch

Maintenance, accessories, operation. Anything to do with making your erg work.
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windy_miller
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Model C slipping Clutch

Post by windy_miller » May 26th, 2020, 5:31 am

Hi Guys
I've an old C2 model C, recently put in the Chain Axle Sprocket Replacement Kit.Everything was fine. But since I've moved it into the garden shed ( not sure if this has anything to do with it )I have noticed it slipping in around every 50 strokes.
I took off the flyweel, oiled it well and it stopped for a couple of days but seems to have comeback :shock:

I have been looking around for a replacement flywheel part number 1740) but I can't find any in the UK.
Question Or
  • if anyone knows where I can find simple step-by-step actions to replacing a clutch bearing?

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Carl Watts
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Re: Model C slipping Clutch

Post by Carl Watts » May 26th, 2020, 7:15 am

Do a search on this forum. Its really hard to do yourself unless your an engineer and can make your own bearing puller.

The bearing can also be replaced with a superior version of it but its a lot more expensive.

Have seen replacement or exchange hubs listed on Ebay but technically your not supposed to remove the 3 screws that hold it in as you could upset the balance of the flywheel fan assembly.
Carl Watts.
Age:56 Weight: 108kg Height:183cm
Concept 2 Monitor Service Technician & indoor rower.
http://log.concept2.com/profile/863525/log

jamesg
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Re: Model C slipping Clutch

Post by jamesg » May 27th, 2020, 12:29 am

I've moved it into the garden shed
Temperature? When I move mine outdoors, if below about 12C I get the occasional freewheel pull.
08-1940, 183cm, 83kg. Last seen MHR 140.
2024: stroke 6 W-min @ 20-21. No times yet, now using WODs.

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Carl Watts
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Re: Model C slipping Clutch

Post by Carl Watts » May 27th, 2020, 4:54 am

Basically those bearings can just fail. The one in my model D died and it got regular lubrication but the one in my older model C is still going. Typically they never get lubricated and that doesn't help. The one concept 2 fits in the factory is from a quality manufacturer Koyo but you can upgrade it to the one with stainless steel leaf springs in rather than the one fitted that uses the plastic of the cage as springs. The Koyo part number is
RC-121610-FS if you want to upgrade.
Carl Watts.
Age:56 Weight: 108kg Height:183cm
Concept 2 Monitor Service Technician & indoor rower.
http://log.concept2.com/profile/863525/log

nick rockliff
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Re: Model C slipping Clutch

Post by nick rockliff » May 27th, 2020, 1:08 pm

jamesg wrote:
May 27th, 2020, 12:29 am
I've moved it into the garden shed
Temperature? When I move mine outdoors, if below about 12C I get the occasional freewheel pull.
That's what I found too, take the flywheel off and clean out all the old lubricant. Apply new lubricant and all should be well. Use light oil not grease.
67 6' 4" 108kg
PBs 2k 6:16.4 5k 16:37.5 10k 34:35.5 30m 8727 60m 17059 HM 74:25.9 FM 2:43:48.8
50s PBs 2k 6.24.3 5k 16.55.4 6k 20.34.2 10k 35.19.0 30m 8633 60m 16685 HM 76.48.7
60s PBs 5k 17.51.2 10k 36.42.6 30m 8263 60m 16089 HM 79.16.6

windy_miller
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Re: Model C slipping Clutch

Post by windy_miller » June 9th, 2020, 5:36 am

Thanks for the quality responses.

Since writing this post, it's been behaving itself.
I do think it's temperature related as I've changed my rowing times from early morning 6am to lunchtimes.

As it's over 20yrs old, I think this is going to happen again so I contacted C2 and they have the PN1740 flywheel (Balanced C) back in stock from 6th June (£68.33 +VAT). They don't sell the clutch on it's own as a spare part as they had customers that unbalanced the flywheel when they changed it and once unbalanced it's hard to get it right again.

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Carl Watts
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Re: Model C slipping Clutch

Post by Carl Watts » June 9th, 2020, 7:02 am

It can be changed without removing the hub but that makes it a large object to freight about if someone else does it. Just try a drop or two of oil on it.
Carl Watts.
Age:56 Weight: 108kg Height:183cm
Concept 2 Monitor Service Technician & indoor rower.
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ghart23
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Re: Model C slipping Clutch

Post by ghart23 » February 26th, 2024, 1:27 am

To Carl Watts

I have a Model D Concept 2 and have noticed that during a rowing stroke there is almost no resistance during the first 1 to 1 1/2 feet of the stroke.

Is it customary for the one-way roller clutch not to engage until that point, or does the stroke have to start more briskly for the clutch rollers to immediately wedge into their cages?

Otherwise the action is smooth a silk and noiseless.

I would just like the resistance to engage more quickly during the leg thrust part of the stroke.

We're lucky enough to have a large river our front yard faces and would love to have the concept 2 rowing machine feel more like what we experience with Concept2 oars in our shells during the summer.

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Ombrax
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Re: Model C slipping Clutch

Post by Ombrax » February 26th, 2024, 1:42 pm

ghart23 wrote:
February 26th, 2024, 1:27 am
Is it customary for the one-way roller clutch not to engage until that point, or does the stroke have to start more briskly for the clutch rollers to immediately wedge into their cages?
Since Carl hasn't replied I'll provide my $0.02

Based on my experience on a number of different C2 rowers, when used properly a clutch that is in good condition engages essentially instantly at the start of the drive. For what I've read here, there are two things can cause problems: 1) a newbie user who just isn't putting enough "umph" into his/her drive to catch up with the flywheel, and 2) a bad clutch. Based on your statement that you're an OTW rower I'm thinking that you have enough experience for it not be (1) and therefore it sounds like it's (2).

If you look around there are several threads that discuss how to flush/clean out and re-lube the bearing to hopefully get the clutch back to 100%.

Good Luck

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Carl Watts
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Re: Model C slipping Clutch

Post by Carl Watts » February 26th, 2024, 5:41 pm

With a fast explosive drive and a decent one way the clutch will engage within a few inches at the start of the drive.

Essentially your body has no resistance at the start of the drive except a few pounds of shock cord resistance so it shouldn't take long for the rotational speed or rpm of the chain sprocket/drive shaft to exceed the rpms of the fan.

The one way or clutch bearing should engage the moment the the shaft rpms exceeds the fan rpms. As the fan starts decelerating at the end of the drive, the rate at which depends on the drag factor setting the fan speed should have dropped significantly during the recovery before the next drive.

Mine grabs with no perceived dead zone at the start of the drive.
Carl Watts.
Age:56 Weight: 108kg Height:183cm
Concept 2 Monitor Service Technician & indoor rower.
http://log.concept2.com/profile/863525/log

ghart23
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Re: Model C slipping Clutch

Post by ghart23 » February 26th, 2024, 10:14 pm

Thanks Ombrax and Carl

Both of your inputs were a helpful start on sorting this out.

Carl: Is there a source you would recommend for an upgraded one-way roller clutch bearing for a Model D?

Thank you

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Carl Watts
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Re: Model C slipping Clutch

Post by Carl Watts » February 26th, 2024, 10:26 pm

Google Koyo RC-121610-FS

Any decent bearing shop in your area that sells Koyo will be able to source it.

I got mine sent out of the USA from an E-Bay supplier because we get ripped off here in New Zealand and they are like 4 times the price.

It was years ago I got mine, ordered like 4 of them at the time, have repaired a few peoples Ergs with them over the years.

Getting the bearing is the easy part, swapping it over without the right gear is the hard part.
Carl Watts.
Age:56 Weight: 108kg Height:183cm
Concept 2 Monitor Service Technician & indoor rower.
http://log.concept2.com/profile/863525/log

ghart23
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Re: Model C slipping Clutch

Post by ghart23 » February 27th, 2024, 12:17 pm

Thanks Carl

I will look into that

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