Which Chainring

stevephotoman125

In September I am doing a solo ride of 310 miles for Rainbows Children's Hospice. I'm currently rebuilding my 1979 Carlton Corsair which currently has a 52/42 chainset at present. As the ride involves quite a few hills would I be better off changing the 42 to a 36. I'm rebuilding on a budget and the 36 is the only compatible chainring I have.
I won't be carrying a heavy load about 10kg in all and the ride will be over 3 days.

maddog 2

and the 36 is the only compatible chainring I have

What chainset is it? Or better still, what is the distance between the c/ring bolts? Or better still what's the BCD? My first impression was that 36 won't fit a standard double, which it sounds like you have.

stevephotoman125

Sorry should have said its a Stronglight chainset and so is the 36. Although the bike is a 1979 Carlton Corsair it had been upgraded by the previous owner. Everything lines up between them so if it does help me with uphills all I need to do is unbolt the 42 and put the 36 in it's place

racingcondor

Another problem you may run into is that there is a limit on how large the jump that the front derailleur can handle. 53-39 and 50-34 are about on those limits so you may find front shifting is slow and clunky or that the chain snags on the bottom of the cage when you shift to the small ring.

No idea if this will be a problem for you or if it's a creation of more modern shifters. I'm sure Stronglight can supply whatever you need (it's a pretty huge range they have) so good luck.

Monty Dog

Most double front mechs have a maximum capacity of 16 teeth, so if you're running a 36 inner, it should be OK with a 52 outer - only way is to try.