Velobuild VB-R-218

[Sebastian]

Turns out my aftermarket 11sp chainrings don’t play well with 12sp chains. At least on the inner ring the chain skips on steep inclines. On the big ring it’s fine probably because the chain is engaging on more teeth.
I’ll replace the inner ring now with a Super Record 12sp one and see if that fixes things.

[madmax]

Turns out my aftermarket 11sp chainrings don’t play well with 12sp chains. At least on the inner ring the chain skips on steep inclines. On the big ring it’s fine probably because the chain is engaging on more teeth.
I’ll replace the inner ring now with a Super Record 12sp one and see if that fixes things.

Use the 11-34  Super Record 12spd cassette. Don't alter chain length till you test it.
I think I sent you a detailed parts list one of our earlier emails so your build parts should be identical

Let me know if you have any issues & I'll help out

[Sebastian]

Use the 11-34  Super Record 12spd cassette. Don't alter chain length till you test it.
I think I sent you a detailed parts list one of our earlier emails so your build parts should be identical

Let me know if you have any issues & I'll help out

I don’t think the cassette is to blame here. It shifts fine. The chain is skipping on the chainring. Exactly why I’m not sure yet. If the problem was cross chaining, then in theory it should be just as bad if not worse when on the big ring as cross chaining is much worse when in big/big. Yet it doesn’t happen. I continued my ride climbing in the big ring, therefore cross chaining much more and no chain skipping. I can also see the marks on the inner chainring so I’m sure this is where it happened. It is a set of chainrings of the same type. Aftermarket Campy rings from TA Specialites in France. But for some reason it only happens on the small ring. I’ll see if a different inner ring fixes the problem.

[Sebastian]

I think it is widely accepted that with 12sp, you can use 11sp chainrings and people even use 12sp chains to quieten down their 11sp drivetrains, but it might not work perfectly. Remember how much trouble the pro peloton had when Shimano introduced 12sp but couldn’t supply whole groupsets? The teams combined 12sp groups with 11sp powermeter cranksets. The result was that guys were dropping their chains left and right.
I think I just stumbled upon a particularly bad combination here.

[madmax]

I think it is widely accepted that with 12sp, you can use 11sp chainrings and people even use 12sp chains to quieten down their 11sp drivetrains, but it might not work perfectly. Remember how much trouble the pro peloton had when Shimano introduced 12sp but couldn’t supply whole groupsets? The teams combined 12sp groups with 11sp powermeter cranksets. The result was that guys were dropping their chains left and right.
I think I just stumbled upon a particularly bad combination here.

I get a chain drop when I am in my large in the front & use the left & right thumb shifters to drop to small in front & rear simultaneously
This has happened a couple of times so I stopped doing that  & my bike tech Yao said that he had set the FD cable as tight as possible for a smooth shift & it does shift nicely

Put your bike on a stand & record the gears as you spin the crank & switch gears & lets see what is goin on & email me the video

[JonMS]

I got some new wheels and tires 
Reserve 34|37 wrapped in GP5000 TR 30c
Bike rides totally different now

[Sebastian]

I get a chain drop when I am in my large in the front & use the left & right thumb shifters to drop to small in front & rear simultaneously
This has happened a couple of times so I stopped doing that  & my bike tech Yao said that he had set the FD cable as tight as possible for a smooth shift & it does shift nicely

My chain does not drop when shifting. The FD shifts just fine both ways. I was just making a point about the limited compatibility between 12sp chains and 11sp chainrings.
I have a 12sp inner ring with me tomorrow. I’ll install that and see if it fixes things. I’ll give an update then.

[Sebastian]

I discussed my issue over on the WW forum. Graeme Freestone King, pro mechanic and UK Campag distributor chimed in. He confirmed that my chainrings are to blame. There's already limited compatibility between original Campag 11sp rings and 12sp chains, usually at least resulting in accelerated wear. Now I'm running aftermarket chainrings, so compatibility is unknown. Shimano as well advises against combining 11sp chainrings and 12sp chains. I'm switching over to 12sp chainrings now.
I did another ride yesterday. I got around 400k on this groupset now and I can definitely see wear marks on bot chainrings that weren't there when I was using 11sp chains. I was hoping I could get around swapping chainrings, but oh well. So be it.

[madmax]

I discussed my issue over on the WW forum. Graeme Freestone King, pro mechanic and UK Campag distributor chimed in. He confirmed that my chainrings are to blame. There's already limited compatibility between original Campag 11sp rings and 12sp chains, usually at least resulting in accelerated wear. Now I'm running aftermarket chainrings, so compatibility is unknown. Shimano as well advises against combining 11sp chainrings and 12sp chains. I'm switching over to 12sp chainrings now.
I did another ride yesterday. I got around 400k on this groupset now and I can definitely see wear marks on bot chainrings that weren't there when I was using 11sp chains. I was hoping I could get around swapping chainrings, but oh well. So be it.

Now you will be 100% Campagnolocal3rdpartyparts

Let me now about your chain length/number of links, since we discussed this earlier. Your large-large combo issue should go away

Cleaned out cassette and chain yesterday with degreaser & used Finish Line  Dry Lube & there was zero "clanking" on the ride to the beach & back & shifting was very smooth

[JonMS]

Noticed a crack in my seatstay the other day. Opened an inquiry with velobuild about a warranty exchange. Anyone else have any experience with it?

[Sebastian]

Where exactly is this on the seat stay? Rather close to the seat tube junction by the looks of it? Weird place for a crack to happen IMO. First step would probably be to sand a way the paint and inspect the carbon. Chris/Velobuild will probably ask you to do this anyway.

[JonMS]

Where exactly is this on the seat stay? Rather close to the seat tube junction by the looks of it? Weird place for a crack to happen IMO. First step would probably be to sand a way the paint and inspect the carbon. Chris/Velobuild will probably ask you to do this anyway.

Yep that is where it is. I will wait for velobuild response before sanding. Dont want to get blamed for anything by jumping ahead. I sent pictures as well as a video showing the crack flexing under load.

[Sebastian]

It might have to do with the dropped stays. That creates more stress in this area. Still it shouldn’t happen of course. Let’s see how VB handle this.

[JonMS]

It might have to do with the dropped stays. That creates more stress in this area. Still it shouldn’t happen of course. Let’s see how VB handle this.

They are replacing the frame. I will keep this updated if/when I get tracking information and frame.

[Sebastian]

There's already limited compatibility between original Campag 11sp rings and 12sp chains, usually at least resulting in accelerated wear. Now I'm running aftermarket chainrings, so compatibility is unknown.

I fit 12sp chainrings to my cranks today. 52/36 teeth combo. This seems to have fixed my issues. Chain runs quieter now. Front shifting is smooth. No chain skipping anymore on the small ring. I rode up a steep incline and everything was smooth. I deliberately tried to make the chain skip but it wouldn’t. So all good now.