Campy 10 with Shimano 8 cranks: Chain lodging between chainrings

[Phil, Squid-in-Training]

Just for future Google groups reference, my Connex 10sp chain lodged itself
between my 39t and 53t chainrings on my Shimano 8-sp 105 cranks while
downshifting a week ago. I can't duplicate it, and it's only happened once
in a couple hundred miles. There was no jamming, as the chainrings have
pseudo shifting ramps that kept the chain from wedging. I shifted down a
bit and all was well.

--
Phil, Squid-in-Training

 

[Qui si parla Campagnolo]

Phil, Squid-in-Training wrote:
> Just for future Google groups reference, my Connex 10sp chain lodged itself
> between my 39t and 53t chainrings on my Shimano 8-sp 105 cranks while
> downshifting a week ago. I can't duplicate it, and it's only happened once
> in a couple hundred miles. There was no jamming, as the chainrings have
> pseudo shifting ramps that kept the chain from wedging. I shifted down a
> bit and all was well.
>
> --
> Phil, Squid-in-Training

Not surprising and a wee bit of let up on pedal pressure while shifting
will prevent this. Something that once upon a time, with friction
shifters, that was common, for front and rear ders shifting, now
seemingly lost in the haze of automatic transmissions.

 

[Robin Hubert]

Qui si parla Campagnolo wrote:
>
> Phil, Squid-in-Training wrote:
>
>>Just for future Google groups reference, my Connex 10sp chain lodged itself
>>between my 39t and 53t chainrings on my Shimano 8-sp 105 cranks while
>>downshifting a week ago. I can't duplicate it, and it's only happened once
>>in a couple hundred miles. There was no jamming, as the chainrings have
>>pseudo shifting ramps that kept the chain from wedging. I shifted down a
>>bit and all was well.
>>
>>--
>>Phil, Squid-in-Training
>
>
> Not surprising and a wee bit of let up on pedal pressure while shifting
> will prevent this. Something that once upon a time, with friction
> shifters, that was common, for front and rear ders shifting, now
> seemingly lost in the haze of automatic transmissions.
>

Amazingly, something that doesn't happen with wider chains that matched
the chainring spacing better. This didn't effect old "manual" 5-8spds.

It has been noted here in the past that this is a "feature" of running
super narrow chains on older cranks. I shift with finesse, thank you,
since my front derailleurs work on friction (Shimano barcons, Campag.
ergo). It still happens, occasionally. And this is with 9sp chains on
"8sp" cranks. Strangly, it never happened on my Campag. "8/9sp" crank.


Robin Hubert