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Repair a Campagnolo Record 10 Speed Compact Carbon Crankset?
 

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BobB
Joined: 13 Jan 2004
Posts: 170
Location: Columbus, OH

8/26/17 12:05 AM

Repair a Campagnolo Record 10 Speed Compact Carbon Crankset?

Can anyone repair the pedal holes in a Campagnolo Record 10 Speed Ultra Torque Compact Carbon Crankset?

My friend and his shop have searched in vain for a replacement crank, but if anyone knows a source, please let me know.

The pedal holes were found to be damaged after he removed the 20mm pedal extenders he uses. I have not seen it, but he said you could see loose carbon fibers in the holes. From his description I thought the pedals might screw directly into the carbon arm, but in all of the pictures I have seen of this crank, it appears to have threaded metal inserts for the pedal to screw into. Regardless, for many years there have been comments on this forum from time to time that most anything carbon can be repaired.... So, any suggestions for repairing a crank? Calfee maybe?

--BobB

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4144
Location: Nashua, NH

8/26/17 5:08 AM

It does have metal inserts

If your friend can see carbon fiber in the holes, he's done some serious damage and the crank is probably toast, but as you said, pictures would help. It makes me wonder if he tore the inserts out along with the pedal extenders.

I've seen these cranks both new and used, so I don't know why he's having problems finding one. If he can't find the 10-speed version, tell him to buy the 11-speed; it will work just fine. I've got one on my primary road bike and it works great with 10-speed shifters, derailleurs and cassettes.

Why is he using long pedal extenders? They put a huge amount of extra stress on the crank, particularly if the rider is heavy as well.

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BobB
Joined: 13 Jan 2004
Posts: 170
Location: Columbus, OH

8/29/17 7:28 PM

I am still trying to get pictures, but I think you are correct that he must have torn out the inserts along with the pedal extenders. As you said, the crank is probably toast.

He likes to remind us that Mark Cavendish (effectively) uses pedal extenders.

I have ridden behind him on many rides in the last 20 years and his pedal stroke is clearly much better with the pedal extenders. He rides many, many miles every year (he is the Regional Brevet Administrator of the local RUSA group, Ohio Randonneurs) and added the extenders only after working with capable bike position fitters. And no, he is not a flyweight, so he probably does put a high amount of stress on the crank arms and holes. I do wonder whether the extenders were installed with some kind of anti-seize product. He is a good bike mechanic and I assume he used the usual grease on the threads.

He is already considering the 11-speed crank, but he was hoping to find a 10-speed.

-Bob

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dddd
Joined: 11 Jan 2004
Posts: 3214
Location: NorCal

8/29/17 9:28 PM

I've seen a couple of carbon Campag crankarms over the years that had to be discarded when a pedal insert became dislodged.

I don't think that there is anyone who would certify their repair of this malady, so of course no good shop would try gluing it back in.

I would recommend that he consider using a Shimano crankset, or perhaps the Rotor 3D30 (it's matte black). Rotor even makes threaded bottom bracket cups that allow fitting the 30mm spindle into a traditional threaded bb shell!

I have a new Rotor 3D30 sitting around that I took off of a new Cervelo R5, with 172.5 arms and round 52-36 chainrings. I'll beat anyone's price on this.

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greglepore
Joined: 10 Jan 2004
Posts: 1629
Location: SE Pa, USA

8/30/17 6:32 AM

I suspect the eyes are merely bonded in place, and the extenders were likely seized, and he ripped the eyes out.

Carbon itself is bonded to metal with with epoxy in its original construction, so I'd try either the appropriate west system epoxy or good old jb weld. I know that will raise eybrows, but I suspect it would work. No shop will try this because its cowboy, but I'd go with it.

Older Campy carbon cranks are hard to find in compact, but Ultratorque doesn't look vintage, so I'd just go mod if I had to.

Will post some pics of a set of Lightweight Standard 3's that I bought ultra cheap and am repairing at the moment once done. Carbon repair isn't rocket science.

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daddy-o
Joined: 12 Apr 2004
Posts: 3182
Location: Springfield

8/30/17 7:36 AM

Out of my wheelhouse with this one but if someone is going cowboy are there any properly threaded items with a flange to go on the frame-facing sides of the crank arms? You know, something for a generous bonding surface. Would something Heli-Coil-like be appropriate? The alignment jig alone might be the price of a crankset.

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dddd
Joined: 11 Jan 2004
Posts: 3214
Location: NorCal

8/30/17 8:55 AM

It's been quite a few years now, but I seem to recall that the insert has a threaded OD that matches threads in the carbon(?).

Possible problem then is why the original bond failed, so would simply re-bonding be strong enough with any less-than-ideal bonding agent?

Like with any part though, if you repair it, it's considered modified and only the repairer will be blamed for any sort of subsequent failure, bar none.

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greglepore
Joined: 10 Jan 2004
Posts: 1629
Location: SE Pa, USA

8/30/17 8:19 PM

The original bond failed, most likely, because it was never engineered for the lever arm that a pedal extender that was sorta seized would present. Glue em in, neverseize the threads and call it a day.

Doesn't sound like he's a sprinter, he'll be ok.

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4144
Location: Nashua, NH

8/31/17 9:36 AM

If there are threads in the carbon...

...there's a reasonable chance of getting the insert aligned properly. If there's nothing to align the insert, I'd definitely pass on trying to repair it. It's also a high stress component and the risks related to failure range from the inconvenience of having to pedal one-legged to a crash and potential for serious injury. Some things are not worth trying to repair and my gut says this is one of them. I would never feel comfortable trusting it.

There's also the issue of getting the inserts off of the pedal extenders. If they're seized badly enough that they ripped out of the crank the odds of getting them off without having to cut them are pretty low. Perhaps heating would help, but that could also ruin them if they're aluminum.

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BobB
Joined: 13 Jan 2004
Posts: 170
Location: Columbus, OH

10/23/17 1:21 PM

My friend ended up just buying an 11-speed crank; it works fine, as was suggested.

FWIW, He says there were no inserts in the pedal eyes of his damaged 10-speed crank.

A carbon frame repair outfit Google found, Appleman, https://www.applemanbicycles.com/repair/ , will repair frames but not components -- "it's cheaper to buy a new part" (but he doesn't mention cranks). Calfee Design on their site also generally excludes components but does not specifically reject cranks.

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4144
Location: Nashua, NH

10/24/17 5:27 AM

Considering that cranks are the highest stressed components on a bike, I'll bet that neither outfit would even consider repairing one.

FWIW, since this thread started, one of my FSA cranks has developed play in one of the pedal inserts. That crank is now off the bike, permanently.

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