question about older chainring for my late 90's Bianchi
 

thinking of get another crankset/ chainrings for my Champion D'italia. But don't know what kind of model I should get? I am looking some ebay bids like this one for example:

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Nice used vintage Campagnolo TRIOMPHE VICTORY Crankset

Crank arms 170mm

116BCD. Left crank has some scratches and scuffs.

Chainrings 52/42T

9/16x20F threads

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What is 116BCD mean? 9/16x20F ?

Thanks!

first of all why do you wish to change your crankset? if you are looking to change your gearing it may be easier to change the chainwheels on your current ones.

more often then not changing crankset requires changing the bottom bracket aswell. all cranks are designed to work with a spefic lenght spindle. sometimes changing from a shimano 105 to a 600 of approximatly the same year you do not need to. going from what you have to a Triomphe crank will most certainly require you to do so.

116BCD refers to how far apart the chainwheel bolts are. most shimano road (non compact) are 130BCD, Campi 135BCD

9/16x20 refers to the threading for the pedals (this size is pretty standard these days but when Triomphe was made some cranks still came in french threading)

Yes. I just would like to change my gearing ratio. I mentioned this Champion D'Italia before. I got it as a single speed and then swap the 48/42chainring & cassette from my crashed cross-project USA on this Champion D'Italia. I sometime feel the speed is not fast enough on this gearing set-up. And the reason why I am thinking to get a new crankarm set as well is: the cranks arm came with this bike is crank brother's. There is a small crack just next to one of the bolts. It looks like the previous owner had tighten it up too much.
But since you say the crankarm is kindda together with spidle...I probably just ride it until it break. So I just need to get the chainring something like 52/42, right? There is no other standard for the chainring as long as the bolt's position is fit, right? sorry for so many questions! :)

a small crack next to which bolt? a mounting bolt?

aside from the BCD most post '00ish(?) have a different thickness for the narrower 10 and 11spd chains. I am running a few mixed chainwheel combinations, 9spd bike with 10spd 42t and 9spd 52t and having no issues. also there is a trend towards "pairing" chainwheels because of the shifting ramps again I seem to have little shifting issues with mixing these.

I assume you CdI is Campy Ergo equipped so just finding and installing a 52t ring that fits you BCD should get you your top end gearing.

** if that crank is cracked near the bolt for mounting it on the spindle replace it **

my is 8 speed.
I meant those 5 bolts. there is a small crack just next to one of those bolts.
THANKS!