Need Education on Compact Double verses Triple

[Cyclesome]

I recently purchased a Specialized Ruby with a Compact double cassette 50/34. How does this compare to my triple cassette on my Cannondale hybrid which is 28/38/48? Will I be able to climb hills with my compact double? My Ruby is as light as a feather compared to my 30 lbs. Hybrid, but will I have the gears necessary for climbing? I took my Ruby out yesterday and road her for 25 miles, but didn't tackled any huge hills.

I need a basic 101 explanation of these gearing systems. Sorry if I appear unknoweageable, I am still in the learning process.

Thanks!

[Kalidurga]

Whether you can climb hills or not with a compact depends on what your cog range is (which I've been learning the hard way this year ). A 34 tooth chain ring is perfectly sufficient for climbing, I think, if you have a big enough cog in the rear.

Two things I love about my compact chainring: Easier cleaning, and no chain suck

[rij73]

My current bike has a 52-42-30 triple and my new bike is getting a 50-34 double. What I did was make sure to get a 12-27 cassette in the back. The 34 chainring with the 27 in back is only a tiny bit harder to pedal than the 30-26 combo I have currently. The bike will be 6 pounds lighter, so that should make up for it!

Check out this nifty online tool:
http://www.sheldonbrown.com/gears/

If you know the size of your old cassette and new cassette, you can use the tool to see how your new gearing compares to the old!

[HillSlugger]

Chainring teeth divided by cog teeth gives you a power factor. If your largest cogs are the same you'd be getting something like 18% less low gear power from the compact double.

My 35 lb hybrid had a 28/34=0.82 low gear ratio. On my 23 lb triple road bike my lowest is 30/27=1.11 I could climb almost anything on that hybrid, even with the weight penalty.

[Cyclesome]

Added Information for climbing ability comparison

Cannondale Hybrid (Aluminum) 28/38/48 Rear Cogs = 11/32
Specialized Ruby Pro (Carbon) 50/34 Cassette Free Wheel= 12 - 27

Thanks, I begining to learn. Any added comments knowledge is appreciated.

[rij73]

I punched that into the online calculator.

Old bike:
Hardest gear - 115 gear inches (a pretty high gear)
Easiest gear - 23 gear inches (a very low gear!)

New bike:
Hardest gear - 110 gear inches (really high enough unless you are racing!)
Easiest gear - 33 gear inches (harder than before, but still low for a road bike)

So your easiest gear now corresponds to about the 4th lowest gear on the old bike. So, yes, it will be harder to pedal up the hills. The difference in weight will make up for part of that, but you may just struggle a bit until you get used to it if you have big hills to climb! It'll be good for you!

[Eden]

I punched that into the online calculator.

Old bike:
Hardest gear - 115 gear inches (a pretty high gear)
Easiest gear - 23 gear inches (a very low gear!)

New bike:
Hardest gear - 110 gear inches (really high enough unless you are racing!)
Easiest gear - 33 gear inches (harder than before, but still low for a road bike)

So your easiest gear now corresponds to about the 4th lowest gear on the old bike. So, yes, it will be harder to pedal up the hills. The difference in weight will make up for part of that, but you may just struggle a bit until you get used to it if you have big hills to climb! It'll be good for you!

I think the difference in the weights of the bikes will make a great deal of difference - I doubt you will struggle with the new bike.
I have a big old utility bike too - a 34 pounder and it has a lowest combination of 28 - 32, same as your Cannondale, and I use it.

my race bike (Also a Ruby Pro) is a standard double (53-39) with a 27 on the back and I've been able to climb every thing I've come across so far on it. I think with your compact you'll be more than fine.

[rij73]

Nice to hear that the weight reduction makes such a big difference. Makes me excited about my bike that's coming in one week!

[sarahkonamojo]

It really depends on the terrain you ride, your fitness level, and tolerance for pain. I have heard from cyclists with compact doubles who switched to touring gearing because they didn't want to climb standing up. But this is Colorado and we like our mountain passes. I'd suggest that your bike shop be familiar with the terrain you intend to ride and give you assistance in choosing gearing.

There are hills everywhere.

Enjoy your new bike.

sarah

[ladyicon]

I also went from a triple to a compact double (my Ruby expert). I have found the Ruby to be very responsive to climbing, the power goes to the wheels. We have a lot of very long slow hills here, also steep climbers. I find the long slows to be similar to a triple on the ruby, but those really steep climbs are a bit harder.
Just learn how and when to shift and keep that cadence up
Congrats on your new bike !!!

[Triskeliongirl]

If you find the 27 isn't low enough, you can switch it out for an 11/34 which is what I have, but you may also need a longer cage rear derailleur. It really depends what you are trying to climb, and how strong you are.

[Cyclesome]

Thanks for the Info. I just weighed my Ruby and she is 18 lbs with water bottle cages & added mirror. My Canondale was 30 lbs. w/o cages & mirror.

[emily_in_nc]

Thanks for the Info. I just weighed my Ruby and she is 18 lbs with water bottle cages & added mirror. My Canondale was 30 lbs. w/o cages & mirror.

That's a HUGE weight difference -- I suspect you'll be just fine with the compact without changing your cogset. You'll be flying up the hills!

Emily

[rij73]

Yeah, with THAT much weight difference, you may be just fine. If not, you'll have to practice the hills. If you want it easier, the idea of changing the gearing in back works too. But, yes, you would probably require a different derailleur too. I don't think you'll need to do that, though.

Enjoy the new ride!

[Starfish]

When I went from my 40 pound steel mountain bike to my 24 pound aluminum road bike I went from:

26-36-48 and 12-34 to
30-42-52 and 11-27

Even with the huge weight reduction, my legs were used to spinning, and there was an adjustment period. Also, at that time, I had not ridden very much at all, so the change coincided with my tackling hillier terrain than I had before. Those two things together made the transition a little difficult, despite the large weight reduction.

Still, I got used to it and enjoyed riding. Then, I moved a couple years ago to where it is much harder to find a flat-ish ride...the hills are harder to avoid, and the climbs are longer. My aspirations changed, and last year I switched to an 11-32 on the back, including a change to a long derailleur.

I love my granny gears. They have helped me tackle much longer, harder climbing rides, and as a result of the easier gears, I am actually getting stronger than I did without them. My expectation is that in another year or two I am going to get a fancier bike, and I will probably try the compact double. I expect a transition, again, but with the strength I am gaining, ironically, with my granny gears, I think I will be ready.

I had one person (or at least one person who said what they thought out loud! ) consider me a weeny for getting the granny gears, saying I would get stronger without them. But, for me, the granny gears have helped me build my strength and climbing endurance.

Hope all that makes sense, and just offers another viewpoint or experience.