Triple or double – what do I need?

[DTD]

I’m thinking about having a new bike built up. One of the things I want is to be able to get up hills that currently defeat me. So I’ve got a question about gears and whether I should go for a triple or a compact double.

I’m fairly sure the group set will be Campagnolo Veloce. My bike at the moment (Cannondale Caadx 105 cyclocross) has a 46/36 teeth chain rings and a Shimano 10 speed 105 cassette at the back. I find myself running out of low gears and don’t spend that much time on the big front ring and rarely in the highest gear.

So my question boils down do I need a Veloce triple chain ring to get a few lower gears, or is there a double combination in this groupset that will do this? If so, what should I be asking for? Any comments about why one is preferable to the other are also welcome.

Thank you once again for your expertise.

 

[DTD]

Ta. Having a read, now.

 

[DTD]

Now I am confused! ;-) The Veloce options are:
Standard:
combination: 39-52, 39-53
Compact:
combination: 34-50
Triple:
30-39-50

Sprocket sets
11-25, 12-23,
12-25, 13-26,
13-29-

current bike: 46/36 chain ring and a12/28 cassette
so, is there a combination of the compact chain ring and a sprocket set that will give me two or three lower gears than I have at the moment.

 

[Crackle]

Yes, the compact 50-34 with the 12-29 but what gear combination do you most commonly ride now as the 50 is significantly more than the 46 and the rear cog quite similar, so you don't want to find yourself without the gears you currently use most?

 

[slowmotion]

This gear inch calculator might help.
http://cycleseven.org/bicycle-gear-inch-calculator

With your current set-up, your lowest gear (36 chainring/28 cog) works out at 33.76 gear inches ( assuming 700x23 tyres.)

If you chose a Veloce set-up with 50-34 on the front and 13-29 on the back, your two lowest gears would be on the 26T and 29T cogs. These give you 34.34 and 30.79 gear inches. It looks like you get one lower gear than you have at the moment.
I think.

 

[ColinJ]

If you got the triple, you could substitute a 28 or a 26 for the 30-tooth little ring if you needed even lower gears.

I put a 26 on my Basso, which gives me a great low gear for ultra-steep stuff, but the step down from 39 to 26 is too big really, and I will go back up to 30 as my fitness improves.

 

[Mr Haematocrit]

I use a compact as I do not like the chain line on triples which is something rarely discussed in the triple vs compact threads

 

[ColinJ]

I use a compact as I do not like the chain line on triples which is something rarely discussed in the triple vs compact threads

When you think about it, the chain on the middle ring on a triple has a better line over more of the cassette than on either ring of a double, and most riding is probably done on the middle ring over moderately undulating terrain.

As for the other 2 rings on a triple - if you need to be on the big ring, then you should be using the small sprockets, and if you need to be on the small ring, then you should be using the big sprockets.

The chainline is only a problem if you insist on riding big-big or small-small.

 

[Canrider]

So my question boils down do I need a Veloce triple chain ring to get a few lower gears, or is there a double combination in this groupset that will do this?

I think slowmotion is right that the 13-29 and compact will give you a single lower gear than you currently have.

Given what you've written, I'd go for the triple, as you don't say why and whether you'd prefer to have a double instead..

 

[TheDoctor]

Personally, I'd go with the triple and the 13-29 cassette.
I've never thought "I'd love a higher gear" but I've often wanted lower ones...

 

[boydj]

I'm with ColinJ on the chainline issue with a triple chainset. The middle ring keeps you in the middle 6 cogs anywhere between 12 and 20+ mph at a reasonable cadence. Unless you are a serious racer, counting the grams, a triple chainset is a lot more flexible, particularly if you have the one do-it-all bike. I'd go for this every time if it is an option.

The other point about a compact chainset is that I find it hard to get a comfortable cruising gear. The 50 is a tad to high and the 34 is way too low, leading to awkward chainlines for a lot of the time. And the big gap between the chainrings gives a lot of double-shifting. On my own compact I've changed the chainrings to 48/36, which I find a bit more comfortable. If I get close to spinning out on the 48, it's a big downhill and I don't really need to be pedalling.

 

[numbnuts]

Triple your not always young and fit and think of the big hills

 

[slowmotion]

Personally, I'd go with the triple and the 13-29 cassette.
I've never thought "I'd love a higher gear" but I've often wanted lower ones...

Spot on!

 

[TheDoctor]

When i upgraded the groupset, I replaced a triple chainset with a double.
Soon found I needed lower gearing, so went for a compact.
I wish I'd kept the triple.

 

[deptfordmarmoset]

I'm with boydj and Colin for the triple. Mid range riding on a triple means the next gear is just one change away and there's no real cross chain issue. With a compact I find that the next gear in the mid-range involves a double change, front and back, more often.

It may be that Mr Haematocrit, who weighs about 50kg and that's including the bike, is more suited to a compact on his very lightweight bikes.