Campagnolo 12-30 and short cage

[oldpotatoe]

Finally got one of these and tried it on a short cage RD, compact crank and gee, it works just fine and dandy. No medium cage needed, ala 13-29.

Didn't change chain length, enough chain for big-big and no droop is small-small-same chain length as on the 13-29 it replaced.

There may be some frames with shortish der hangers but for the frames I tried, worked fine..for info-

[ultraman6970]

What frame was that?

[Charles M]

I'm way way far away from trying to tell you anything you don't already know but the explanation in got from campy was that it will work but isn't designed to work in that fuller range of motion over time.

[oldpotatoe]

What frame was that?

Waterford, Gunnar, Moots and a frame my employee has made by the builder at GT when he worked at Schwinn.

For Charles, yep, I know what Campagnolo says, like a lot of things they and shimano and others 'say' but like to try them to see.

shimano says you can't use a 11-32 with Di2 but I know some have done that.

Ideally, starting from a new build, buy/use the new medium cage rear der but
if you have the drivetrain and want to just use a 12-30..it won't hurt anything as long as the chin length is correct.

[ultraman6970]

I have a 29 and had to move the screw to the limit because the cog teeth were way too close, still noisy but works, besides im using normal crankset and probably adding 2 links to the chain could help more. As you say (never thought on that), if the rd hanger is a few mm longer then it should work.

[Dave]

Chainstay length is also a factor. Frames with the best length can gain up to 3T of wrap, over ones with the worst length.

Using the rigorous chain length formula, found at the Park Tool website, you can predict the results. If the answer is only a fraction of an inch over an even number, like 53.25 inches, you'll probably need a 54 inch chain, yielding 4T of additional wrap, when you're only 1T short.

It's not a big deal, but the chain might hang loose in a couple of the smallest cogs, when using the little ring.

[Chance]

...........

Ideally, starting from a new build, buy/use the new medium cage rear der but
if you have the drivetrain and want to just use a 12-30..it won't hurt anything as long as the chin length is correct.

Thanks, good information to know. This 12-30 cassette option sounds great to me for the few occasions that we may need temporary lower gears for a special event, but don’t quite see why more than a few would want to start with a 12-30 from the onset on a new build.

If starting from scratch why not go with 11-28 cassette and downsize chainrings as needed? Unless we are already at the bottom of the size range and can’t find smaller rings that’ll work for us. And there are always choices unless we want to keep it all Campy.

If starting with a “normal” compact and 12-30 cassette there isn’t much room to re-gear down if we need to without major work and expense. My personal preference is always to start at the middle to upper range of gearing for the equipment’s range so changes can be made easily in either direction. Particularly to lower gearing which seems to come up more often.

[oldpotatoe]

Thanks, good information to know. This 12-30 cassette option sounds great to me for the few occasions that we may need temporary lower gears for a special event, but don’t quite see why more than a few would want to start with a 12-30 from the onset on a new build.

If starting from scratch why not go with 11-28 cassette and downsize chainrings as needed? Unless we are already at the bottom of the size range and can’t find smaller rings that’ll work for us. And there are always choices unless we want to keep it all Campy.

If starting with a “normal” compact and 12-30 cassette there isn’t much room to re-gear down if we need to without major work and expense. My personal preference is always to start at the middle to upper range of gearing for the equipment’s range so changes can be made easily in either direction. Particularly to lower gearing which seems to come up more often.

Mountains here, we sell a lot of compacts and 13-29, 12-30(shimano).

Starting from scratch, and start to swap rings on a new build? Doubt it.

But gearing is personal. a 50-11 is a HUGE gear(bigger than 53-12), and hardly anybody needs a 11, particularly when you lose the 16 or 18.

[Chance]

Mountains here, we sell a lot of compacts and 13-29, 12-30(shimano).

Starting from scratch, and start to swap rings on a new build? Doubt it.

But gearing is personal. a 50-11 is a HUGE gear(bigger than 53-12), and hardly anybody needs a 11, particularly when you lose the 16 or 18.

To my question, what happens when they start with a compact and 13-29 or 12-30 and then put on weight, get older, out of shape, or simply find a steeper hill to climb. Then what? Spend a lot more money rebuilding much of the drivetrain?:confused:

Maybe don't understand your answer, but why buy or sell a product that is already at the edge of being maxed out?

And for what it's worth, if 50-11 is too huge a gear (and it is huge) there is always 46-11 or whatever it takes to customize to the owner's need while maintaining some future flexibility to modify. Don't see that in itself as an issue (unless the owner wants all Campy) and can't get a smaller ringset.

[druptight]

I can't wait to pick up the new 12-27 personally. The longtime void in the 10sp cassette between 12-25 and 13-29 has finally been removed.

[monkeybanana86]

thank you. I had been wondering about this. Perfect for mountain trails.