Why do the Campy 10 speed 16-12 cogs grind?

[WSBA Jr.]

Folks, I'm stumped on this one. New BB30 carbon frame, with Campy Record 10. Ultra Torque mounted with Praxis adapter. New Zondas, cassette, Record 10 speed chain, tried multiple fresh 53 rings. I checked the need for a spacer for the large ring, installed one to correct thickness (measured a loose .010). Riding hard in the large 53 ring, 53/23 is noisy, it is smooth and silent up until 16 to 15, gets louder with each shift, noticeable drag through 13, slightly better at full speed in 12. Several sets of tubulars, aluminum and carbon, have the same issue. The 39 is quiet as a mouse.

I've also rebuilt the right shifter, very nice click and race performance. Cables are new, it's driving me nuts! The Zondas are the most notable for this issue, though when spun out of the 12 descending Crystal Mountain @50-55mph, they roll great and fast. Been doing this with Campy 10 for a long time...

Any ideas or questions for us? Thanks much.

[sandyrs]

I know the frame is new but the derailleur hanger may not be aligned?

[Ralph]

Am sure you checked this....but are cassette spacers correct? If all loose cog cassette.....thinest spacer between two largest cogs, widest spacer between 6 an 7th cog...counting from small end.

[Black Dog]

I know the frame is new but the derailleur hanger may not be aligned?

This. Also how old is the RD? They do develop some play in the mounting bolt pivot. Also, a new frame may have the hanger at different location compared to your old frame and you may need to look at the B-screw adjustment.

[oldpotatoe]

Folks, I'm stumped on this one. New BB30 carbon frame, with Campy Record 10. Ultra Torque mounted with Praxis adapter. New Zondas, cassette, Record 10 speed chain, tried multiple fresh 53 rings. I checked the need for a spacer for the large ring, installed one to correct thickness (measured a loose .010). Riding hard in the large 53 ring, 53/23 is noisy, it is smooth and silent up until 16 to 15, gets louder with each shift, noticeable drag through 13, slightly better at full speed in 12. Several sets of tubulars, aluminum and carbon, have the same issue. The 39 is quiet as a mouse.

I've also rebuilt the right shifter, very nice click and race performance. Cables are new, it's driving me nuts! The Zondas are the most notable for this issue, though when spun out of the 12 descending Crystal Mountain @50-55mph, they roll great and fast. Been doing this with Campy 10 for a long time...

Any ideas or questions for us? Thanks much.

Chain thru the tab on rear der, not around it?

[fuzzalow]

Chain thru the tab on rear der, not around it?

HaHa! I've done this! And I thought then, as I still do now, that I was an eminently competent mechanic. Versed in all the secrets and traditions of the Tullio way. Beyond reproach. Duh! Wow! I coulda hadda V8. (Slaps self on forehead).

[Black Dog]

HaHa! I've done this! And I thought then, as I still do now, that I was an eminently competent mechanic. Versed in all the secrets and traditions of the Tullio way. Beyond reproach. Duh! Wow! I coulda hadda V8. (Slaps self on forehead).

We have all done this. I have done worse.

[WSBA Jr.]

Thanks to all for your input!
* The new cassette is correctly spaced.

* I have a new derailleur hanger, replacing a failed cheap grade aluminum with CNC 6061 T6 nice piece from Pilo (through their distributor in France).

* I checked the chain routing as suggested by O.P., since I remove the chain for solvent/Dawn soap/heat dry/new synthetic lube prior to each and every ride. Small chain ring purchased from O.P. is on there working perfectly!

* Black Dog was on the money, as soon as I read it, that was my focus. The Record R/der had been used for a short time on a much smaller frame. The B-screw was significantly out of adjustment. As ever, how embarrassing for me to overlook it. I redid the entire set-up, had a successful ride before dinner, smooth and silent the way we love Campy to be! Changing brake pads for the 404's for racing Tuesday evening against MUCH younger racers...need all the help I can get. Thanks BD!

Thank you all again!

[jmal]

Glad you located the problem. One question though. Did I read correctly that you remove, clean, and relube the chain after every ride? Wow!

[soulspinner]

Thanks to all for your input!
* The new cassette is correctly spaced.

* I have a new derailleur hanger, replacing a failed cheap grade aluminum with CNC 6061 T6 nice piece from Pilo (through their distributor in France).

* I checked the chain routing as suggested by O.P., since I remove the chain for solvent/Dawn soap/heat dry/new synthetic lube prior to each and every ride. Small chain ring purchased from O.P. is on there working perfectly!

* Black Dog was on the money, as soon as I read it, that was my focus. The Record R/der had been used for a short time on a much smaller frame. The B-screw was significantly out of adjustment. As ever, how embarrassing for me to overlook it. I redid the entire set-up, had a successful ride before dinner, smooth and silent the way we love Campy to be! Changing brake pads for the 404's for racing Tuesday evening against MUCH younger racers...need all the help I can get. Thanks BD!

Thank you all again!

Good luck on your race. Campy silence reigns......:beer: