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What do you guys think of triple cranksets vs. doubles?(22 posts)

What do you guys think of triple cranksets vs. doubles?Ambishawn
Jan 8, 2003 10:21 PM
Not sure if I should build My new bike with a Double or a Triple. I'm currently using My mountain bike with specialized fat boy slicks on the road and never use the Granny on the road. There are some really steep climbs near Me (the Angeles Crest) that I'd not yet ridden. Most of the hard climbs Id ridden have been off road with the granney gear. I don't plan on using My new bike for loaded touring but don't plan on racing it either. Any Opinions?
Jan 9, 2003 4:17 AM
I never had a triple until this year. Now I am glad I have.
I live in the UK where the hills are short but can be very steep so low gears is a godsend. I find I use 30T inner ring a lot (I even couple a 30T inner ring with a 28T 8 speed cassette for very low gears) and I am a pretty strong rider.

It is also nice to know you have bailout gears if you need them on long hilly rides.

My advice is to get one if you think you will need it. Don't be caught up in the hype that triples are for the weak. I can mash up hills but I prefer to spin as it is better for your knees and easier to keep a rhythm.

I have doubles on my 2 better bikes but a triple on my LeMond winter bike. The only reason I dont go for triples on my nicer bikes (Cougar & Colnago) is for aesthetics. I prefer the clean lines of a double on my best bikes. This is a personal opinion. I do however have a 29T rear cassette on my Campy bike and a 27T on the Shimano bike as I like to have the low gears there if I need them.

In summary, if you need a triple get one but only if you feel you will be happy of the looks of a triple on your new bike. Bear in mind that you may not need a triple where you live but you might if you travel to somewhere very hilly.

My $.02.

Jan 9, 2003 5:07 AM
The real reason for wide gearing...KeeponTrekkin
Jan 9, 2003 6:23 AM
The real reason for wide gearing is, as almost everyone knows is so you can "spin" instead of "mash". What I have never seen posted is the following reason why you want to spin (certainly not the only one): Spinning (while seated) demands less energy output than mashing (while standing) to accomplish the same goal (e.g. get up the hill in the same time, i.e. do the same work!). It's a matter of efficiency; sitting requires less energy than standing. Everyone has a limited power output (ability to do work) while sitting and a higher limit while standing. Most riders can reach their anaerobic threshold while sitting. It therefore requires more energy to deliver the same power while standing, putting you even further into anearobic respiration and an energy consumption rate that is ultimately unsustainable.

The hard thing to do with this knowledge is to know if, where and when it applies to you before you buy the bike. Like one of the other posters, I have wide gearing on my double. Like everyone, I encounter hills I cannot climb seated (my gearing requires a power output I cannot sustain while spinning and seated), so I stand, select a higher gear (more gear inches) and slow the cadence to a level I can sustain for the time needed to climb the hill. If I could climb it sitting in lower gears, I'd waste less energy (as I wouldn't be expending the energy of standing) and would probably be faster, if not on the hill, at least over the distance of the hill and recovery zone. It took me a long time to understand the relationship described above. It leads me to think that a lot of riders who have doubles might benefit from triples.

I echo the common wisedom: don't let aesthetics or image have an undue role in your selection of gearing.
Well put. Excellently detailed & described. (nm)StevieP
Jan 9, 2003 7:35 AM
Sorry, but I have to be a nerd, and clarify your answer...MXL02
Jan 9, 2003 8:23 AM
only because I have reviewed the medical literature on this very subject. Actually, the amount of energy used to perform a specific task, ie, going up a hill, is the same no matter how it is done. By spinning, one uses slow twitch (aerobic) fibers rather than fast twitch (anaerobic) fibers. The theory behind this is that the real limiting factor for cyclists is their lactate threshold, or the level of lactate in the blood that tells your body to stop.
Spinning keeps this lower. But as you will see, your heart rate will still be pretty high.
This explains a query I had but never postedStevieP
Jan 9, 2003 9:21 AM
I ride with Giley D. He has higher gearing than me (30/23 lowest and I have 30/28 lowest).

I weigh approx 30lbs more than him so I use the lower gears
more often for climbing. I am of a more powerful build but when climbing the scales tip in his favour and it is hard to seperate our fitness levels.

When he is churning a 30/23 up a steep hill in the saddle and I am spinning a bit more in my 30/28, we observe the same heart rate effort. We could not figure this out seeing as Giley was perceivably putting in more effort.

Now we know why we have the same heart rate. Spinning is the way to go.Thanks!
Jan 9, 2003 10:12 AM
I'm not an expert in training methods and use of heartrate monitors but heartrate can only be a proxy for power or energy measurement. Oxygen consumption is the only accurate measure for energy "burned" and power at the wheel is the only accurate measure of power produced. Because of this, historically, cycling training focussed too much on oxygen consumption and only more recently did understanding of the anaerobic vs. aerobic mechanisms come to cycling training. This understanding has led to methods using heartrate monitors (about which I know little), but which are probably reasonably accurate and of considerable practical value and, of course, the widely accepted preference for spinning. It's just more efficient and it allows you to have better control over the use of the limited resource of anaerobic respiration.
Don't forget efficiencyKeeponTrekkin
Jan 9, 2003 9:58 AM
Good point, I think you're 100% right as to the biochemistry. However, it's many steps from answering the double vs. triple question. A physics or engineering point: it is correct to say that the amount of energy used to perform a specific task is the same IF AND ONLY IF the efficiency of converting that potential energy to work is the same. No engine is 100% efficient; neither are human bodies or their motions. Moving back and forth, wrestling the handlebars, etc. while standing and pedaling consumes energy that is lost as heat and not converted into work. That additional energy consumption is noticed by the presence of additional lactate and increased respiration. (Don't the elite of many sports train to minimize unnecessary body motion; isn't that another way of saying that "form matters" and not just aesthetics but for bicycling fit, biometrics or aerodynamics - all designed to increase muscle and overall efficiency.)

I believe you're right about the slow and fast twitch muscle fibers and the level of lactate. My post didn't delve into the biochemistry because I've never been able to practically relate it to the original question. I tried to address the factors a rider can notice outside a lab because I've never seen any materials that did so. Perhaps someone can improve my recollection (it's been many years). All body energy starts as food which is converted to glucose(?) through digestion and ultimately ATP for cellular respiration where "everything gets done". I believe aerobic respiration creates something like 38 units of ATP for each unit of suger (glucose?) while anaerobic respiration bypasses the majority of the biochemical breakdown process and creates something like 2 units of ATP and a whole lot of lactate (and associated muscle aches). 2 vs. 38 from the same fuel doesn't sound too efficient. But when the fight or flight response kicks in, you aren't too concerned about efficiency or muscle aches, only getting away from (or fighting) the threat. I think that the anaerobic pathway allows the additional fibers to do work, increasing the overall power provided by the muscles, but at a cost, the buildup of lactate. It's a much more complex question when you need to climb Mt. Ventoux.
Splitting hairs just for the fun of it.MXL02
Jan 9, 2003 11:48 AM
Studies have shown that it is actually not more efficient...spinning can actually use
i more
energy than mashing! What exercise physiologists and coaches have discovered is that it is not how much energy you burn (because it can always be replaced) but HOW you burn it that matters.

Of course, it depends on how you define efficiency, which can be very complex even for an exercise physiologist. But what I think you mean by efficient is that spinning utilizes aerobic rather than anaerobic metabolism, and, yes, in that sense, I can see how spinning could be considered more "efficient" that mashing.
Splitting hairs just for the fun of it.KeeponTrekkin
Jan 9, 2003 1:06 PM
Agreed! And I know I'm learning a few things. I was trying to differentiate between spinning at average cadences while seated and pedaling while standing (again at average but lower cadences) which is the style I think most riders adopt when the power needed can't be supplied seated.

Your point reminds me of a recent post which pointed out that Lance didn't win the first TT of TdF last year because his cadence was too high; he used his computer on the next TT, got his cadence down to the level where the power produced was greater and won...

I also mean aerobic metabolism is more efficient than anaerobic metabolism (biochemically converts a higher percentage of the potential energy in the body to work).

Thanks for your followup
Thanks for the fun discussion...MXL02
Jan 9, 2003 1:42 PM
really helped the day go by!

Ride hard, but ride safe.

Thanks for the fun discussion...KeeponTrekkin
Jan 10, 2003 6:04 AM
I ride where you ride... get a triple !PeterRider
Jan 9, 2003 9:34 AM
If you're interested, on saturday I'll be going up to Mt Wilson with a friend and a cat B student racer whom I don't know yet. My friend and I will probably go relatively slow since we are both recovering from illness, so probably we'll have to ask the racer to wait for us at the ranger stations :-)

i know...manofsteel
Jan 9, 2003 7:09 PM
...what you did last summer...
Still on My MTB w/slicksAmbishawn
Jan 9, 2003 8:33 PM
Where do you start LaCanada or Palmdale/Acton? Gotta work this saturday. Maybe some time soon though. The new bike wont be readey for about a month. Getting the New frame next saturday (Crown Jewel SE).
re: I vote triple for another reason.dzrider
Jan 9, 2003 9:35 AM
I use a triple and a 12-23 which provides an easiest gear that's not greatly different from 39x29 that I could get with a double. I want lots of gears close together in the range I ride most frequently. I'm really spoiled about having a straight block from 42x13 to 42x17 and the triple lets me keep that and still get up most anything New England has offered me.
re: What do you guys think of triple cranksets vs. doubles?Unicoi98
Jan 9, 2003 9:47 AM
Triple is fine if you're concerned that otherwise you'll just end up crawling on climbs. But one other thing to keep in mind is how much improvement you're looking for with the new bike. My experience is that the lower your options are, the lower you'll ride. My old bike had a super granny that I found myself in more often than not. My new bike has got a considerably shorter range and I find that with it I don't really miss the lower gears of the old bike at all. So if part of the reason for the new wheels is to reach a new level of riding, I'd go with the double.
re: What do you guys think of triple cranksets vs. doubles?rodey
Jan 9, 2003 2:50 PM
I just replaced my dura ace double with the dura ace triple for most if not all of the reasons described above...and for one other reason. I live in Colorado and ride in the mountains pretty frequently. Getting up was not the big problem...I have enough gear range and am a strong enough rider to get up the hills with my double. I was having a very tough time going down! Some of the passes I go down have me calling for a bigger gear only to find out I am already there! So my reasoning was basically to get down hills safer ( not spinning so fast ) and hopefully faster :-)
re: What do you guys think of triple cranksets vs. doubles?Tarantula
Jan 9, 2003 5:24 PM
I have to agree with Unicoi98 concerning using the lowest gearing available. When I first got my triple I'd drop down to the lowest I had on some of mild climbs around here. I started with an 11-23. After a while I switched to a 12-25 so that I would have a bigger range in the middle ring. Then I did some mental training (no small feat in my case) to teach myself to use higher gearing. Now I'm to the point where the small chain ring is a last resort, not an easy go-to. My knees are still fine.
re: What do you guys think of triple cranksets vs. doubles?pa rider
Jan 10, 2003 3:14 AM
I'm late on this post, but which triple gears are you looking at. I have a triple (30,42,52) and use the 42 most of the time. It helps alot on the flat areas, but kills you on strong head wind days.

Did you decide if the 30,40,50 (campagnolo racing T) range works for you or the 30,39,52 (durace groupo), beside the traditional 30,42,52 range? I'm a spinner because it easier on my knees.

I'm going to build a cross bike next winter, so I'm going to go with a lesser crank chainring than the tradition triple setup. Just thought I would point out that you should also look at which triple setup you feel is better for the roads you normally ride.

Jan 11, 2003 6:22 PM
What component group are you going with? if you go with ultegra, there aren't different shifters for double verse triple. If you decide that you don't need the small ring have it removed and adjust your limiter screws on the front der. Best of both worlds.