Author Topic: Chainring selection  (Read 309 times)

Chainring selection
« on: January 08, 2019, 06:15:34 pm »
I'm currently running a Shimano Tiagra 9 speed triple chainset (52T/42T/28T) on a Specialized Allez from 2004.

It requires new middle and outer chainrings again (BCD is 130mm) and in the past I bought replacement Stronglight Dural chainrings which worked fine but I can't remember if the outer I bought was triple specific

For the outer this time I was looking at the Stronglight Zicral from Ribble as it is on offer.

Stronglight Zircal Chainring

In the Q and A they reply to one question by stating these chainrings are intended to be used on a double chainset only.
 
I haven't managed to find an outer ring anywhere that say's it specific to a triple or is there no such thing and the one from Ribble is fine to use as it has the right BCD?

Re: Chainring selection
« Reply #1 on: January 09, 2019, 01:31:05 pm »
AFAIK it's only the middle ring that is ever double/triple specific, but you may want to wait for others to confirm.

Old enough to know better, but young enough to do it anyway

Re: Chainring selection
« Reply #2 on: January 09, 2019, 02:57:54 pm »
the 38, 39, 42 sizes will certainly be double-specific unless otherwise stated. The outer chainring sizes (50, 52 of which only the 52 is on sale) will probably work OK but

a) on any chainset the pins and ramps come in matched sets these days; manufacturers sometimes make different 50T chainrings (say) depending on what size chainring they are intended to be paired with. Thus shifting performance is unlikely to be quite as slick as with an OEM chainring if a mixed set is used. Aftermarket chainrings often don't come in matched sets so the shift quality isn't quite as good in any case.

b) the offset requirements for 9s and 10s chainrings can vary slightly depending on the chainset; it isn't absolutely guaranteed that an aftermarket chainring will work perfectly for this reason; some require shims to be added and others won't work at all.

c) the stronglight chainring depicted is for a standard spider, not one with 'a hidden fifth bolt' behind the crankarm.

I'd probably take a punt on it but I note that the ribble website says 'only one in stock' or something, so I wouldn't hold my breath....

cheers

Re: Chainring selection
« Reply #3 on: January 09, 2019, 05:45:03 pm »
Thanks, I've ordered it - hopefully it is actually in stock as it's a good price.