ElCiclista

A question to all of you tandem climbing experts

Are tandems an advantage when doing a timed century that has over 10,000 ft climbing?

The century have 20% grades, one example is a portion that averages 12% grade for over two continuous miles with grades of 20% or more on it. Bellow I wrote some of the considerations to make for the answer.

1. This is a timed century and the objective is to do it as fast as possible, basically ride it just like the single riders and try to finish first. This is very important to consider as is not just finish the century but do it as competition.
2. About 80% of the time will be climbing.
3. The tandem will be a coed tandem. (male-female)
4. Real long climbs(at least 12 miles or longer) and some with very steep sections.

chichi

[QUOTE=ElCiclista;10647409]
Are tandems an advantage when doing a timed century that has over 10,000 ft climbing?[QUOTE]

not likley. if stoker is blind yes

WebsterBikeMan

A tandem provides no advantage when climbing. In about 90% of cases it provides a disadvantage when climbing, while providing an advantage when descending and on the level.
The tandem advantage comes about due to reduced wind resistance per unit motive power. Wind resistance is not a factor when climbing (at least not in any climbs I've ever done).

Whether you are in the 90% or the 10% class (and whether these numbers are right is just a guess) depends on how well the two riders are matched. If you climb at the same speed in the same gear ratio as each other on singles, there will be no disadvantage. Otherwise, it is almost certain that you will not be at maximum power/efficiency at the same cadence, and so one of you will not be contributing on the hill as much as (s)he would be on a single. Given how silly-light they make singles these days, your tandem isn't likely to be enough lighter than the combined weight of your singles, to give a meaningful weight advantage either.

Hermes

Do you own and or ride a tandem regularly with a co-ed stoker or is this a hypothetical question?

pathdoc

I'd be willing to bet you will suffer on this century way more than a single rider.

specbill

[QUOTE=ElCiclista;10647409]A question to all of you tandem climbing experts

Are tandems an advantage when doing a timed century that has over 10,000 ft climbing?

AAAH...NO!!.............. not for this team at least.

Bill J

merlinextraligh

You're at a slight disadvantage on a tandem climbing, due to drivetrain considerations, and coordination of effort between the team members. So it's not the ideal choice for posting a time on a hilly century.

My 2 real world examples, I've done Everest Challenge (15,000 vertical feet a day) and Six Gap (11,000 vertical feet) on both a tandem and a single.

In each instance it was much harder and slower on the tandem.

Not a perfect example because my power to weight ratio (w/kg at FTP) is higher than our teams combined w/kg. However, the difference in power outputs is going to be a consideration in the real world for most any team, unless the two riders are exactly equally matched.

Chris_W

My wife and I have both done rides like this on our single bikes, and last year did one on our tandem. The tandem certainly didn't make things easier, and we finished TWENTY SECONDS inside of the 11-hour cut-off (the ride was 130 miles, 12,500 ft climbing).

There were three or four sections of relatively flat riding, maybe totaling 30-40 miles, where the tandem could have saved us a lot of energy. However, we flew along those, towing the friends we were riding with and several other riders behind us and didn't really use these sections to rest as much as we should have. Even so, the last of these was the final 10 miles, when we found a final burst of energy to go flat out and make the cutoff by such a close margin, with our one friend who was still with us hanging onto our rear wheel whooping in joy - we were really glad to be on the tandem then. The other reason having the tandem helped was that it made it a team effort, and we were able to keep each others spirits up over such a long ride. Plus, the stoker could always use two hands to open energy bars, gels, etc, for the captain and any other riders who were struggling with theirs.

cornucopia72

Assuming the singles can draft off you on the flats and descents... the answer is a resounding: NO

Hermes

You must be referring to the Mount Laguna Classic century which by your other posts, you have done. I see no advantage for a tandem on that course racing for time. First, it is more difficult to draft in a pack of singles on a tandem and accelerations by single riders would be impossible to match on the tandem. You would give more draft than you would ever get. The long climbs would be brutal. You will climb slower than you would on your singles for the same power production which will be frustrating. It will be difficult to do things like change cadence to where you want it for how you feel and ignore your teammate. You may want to spin fast and float in the pedals for awhile to get some recovery and your partner does not. Now, you may both be state / national / world champions and if this is the case, my comment is the same. You will hand out more punishment and go faster on singles on that route.

Tandems are about teamwork and riding together. That is the advantage of a tandem - more fun. If you are looking for a sufferfest/slugfest then ride your single.

conspiratemus1

See my signature. Just more of it with the tandem.

Dean V

It will be slower for the stronger rider than what they could do on a single. If the weaker rider is quite a bit slower then it will be faster for them.
The only way it would be faster is if both of you are similar in ability and it has to be ridden as a TT with no drafting.

Mr. Beanz

Could be talking about Ride Around the Bear Breathless Agony is 12,000 ft). I would think a tandem would be a disadvantge but a couple form SoCal (ALex and Deya/ spelling?) actually took first position on one of the climbing rides ( BA I think, could have been The Bear). Another guy JohnR from SoCal aslo did great on Ride Around the Bear, 5:30'ish. Top 10% of some serious climbers on singles.

conspiratemus1

Another oft overlooked consideration is that in crosswinds (anything but a zero degree headwind, in fact) a tandem has greater wind resistance than two singles because it can't form itself into an echelon. The two of you are both out there in the wind like a barn door getting battered all day long. In a north-south out-and-back with an east (or west) crosswind you would pay a wind penalty (compared to two echeloning singles) in both directions. Although granted this effect diminishes on long steep climbs, mountain country often has winds that conspire to eat away at the tandem team's hope to make up time on the flats and descents. This is in addition to the pure power:weight penalty during climbing alluded to in previous posts.

ElCiclista

Thank you all for the great answers. My question arises from the knowledge that many single riders and some event organizers would consider a tandem an advantage on events that are really suited for climbers and in which group dynamics really play a factor and tandems are drafted until the next climb.

WheresWaldo

I never understood why organizers and single riders think this way. Let's say, all things being equal a tandem team can climb at the exact same speed as the single rider, problem is all things are never equal. Most singles will not take significant pulls at the front when they are riding with a tandem. They believe the tandem should do the bulk of the work. By the time you reach the second or third climb (maybe even the first or second) your team is now tired and the single bikes have fresh legs. The single bikes leave the tandem behind, usually because their selfishness (obvious since they only allow one person on the bike) does not allow them to pace the tandem up the climbs. Your team in your infinite benevolence works even harder on the descent and ride toward the next climb that you catch the group. Again selfishness prevails, the single riders line up behind you and you pull the group to the bottom of the next big climb where they proceed to leave you again. Even before you are done with the ride you are spent and tired of dragging those single rider's sorry asses along the route.

JK

conspiratemus1

^^ That's the kind of ride where you really hope your stoker will fart a lot, and there are no crosswinds to dissipate the toxic plume away from the singles.

merlinextraligh

That makes sense. However, I would have to think that in practice, it would have to be a very substantial crosswind before this effect would outweigh the inherent aerodynamic advantage.

Also, in my experience outside of higher category races, people rarely ride echelons. Riding on roads open to traffic, the traffic generally discourages it. And it lower category races, that lack of knowledge, ability tends to limit the orginzation of effective echelons.

Anyone have any data comparing the effect of crosswinds vs the inherent aerodynamic advantage of tandems?

ElCiclista

I agree.

conspiratemus1

Granted, pro-type echelons that stretch all across the road, or even that take up a whole lane, are rare for recreational riders, and it's especially rare to be able to rotate the echelon for any length of time before traffic breaks it up. But any road on which you can ride two abreast at least some of the time allows a two-deep echelon. And this is the relevant comparison. Two single bikes riding so that the leeward bike is in the sweet spot of the windward will have less air resistance than a tandem where both riders are in the wind. (After all, the "inherent aerodynamic advantage" of the tandem is merely a result of how close the stoker and her half of the bike gets into the slipstream of the captain. If she is not in the captain's net slipstream at all, because the relative wind is 45 degrees to the bike's heading, the advantage is lost.) The effect is easily discernible in crosswinds where the wind speed is close to (or exceeds!) the speed of the bikes. Winds of 20 - 40 km/hr are not uncommon around here especially in the spring.

What we do in our little recreational group that includes two tandems and four to six singles is:
1) If "pure" headwind, the two tandems lead, the singles file in behind each one.
2) If crosswind, the two tandems ride line astern to windward, the singles form a line astern in their lee.
3) If traffic on a narrow road makes any form of two-up riding unsafe, we form a single line astern and all suffer in the wind.
4) The singles wait to let us regroup at the top of hills and don't run away on us because we are friends and we like one another.

Hermes

With respect to eschelons, wind and road races, I competed in a stage race, Cat 5, that included a circuit race and a road race on closed roads. There were sections where the center line rule did not apply. The road race had a square shape. Into the wind, the peloton speed dropped and no one wanted to work. On the downwind section, the speed was fast and the field strung out.

In the cross wind sections we lacked the knowledge to form an eschelon so the Cat 5 men went to the side of the road opposite the direction of the wind and rode fast to string out the field and make the race as hard as possible. To echelon, one would have to ride in the dirt. We continued this tactic on a climb going in the opposite direction. The two accelerations in the crosswind sections resulted in dropping about a 1/3 of the peloton. IMO, a tandem would be toast at that point in the race.

cornucopia72

Maybe on paper, crosswinds are not a huge factor when comparing singles to tandems. On the road, crosswinds are definitely something to reckon with and the tandems struggle with them much more than the singles. Just the other night after taking a hard turn at the front when we moved to the back of the line the guy in front of us did not leave any room for us to shield from the crosswind. So, for all the rotation that we were behind this fellow it was very hard work and we were eventually dropped. That would have never happened if it wasn't for the strong crosswind.

Onegun

Maybe because many tandem riders TELL them not to pull. Fact is, even a lone single rider in front causes us to do more work because they are constantly slowing and accelerating. Not their fault, really. It's just that even a minor wind gust affects a 165 pound rolling mass differently than it does a 300 - 400 pound one!

That is part of the reason that most pacelines of singles will constantly be in the process of accordioning. A 2mph gust slows down the lead rider a bit, and by the time the second rider reacts, he slows down a bit more to allow for a margin of error, etc, etc, on down the line. Twenty men back, the paceline looks like a slinky.

And as we all know, tandems don't accelerate as easily as singles, so this accordion effect cause us a LOT of extra work. And not just the physical, either. Trying to follow the best paceline of singles requires a lot of coordinating of effort between the pilot and stoker.

So ..... whenever we find ourselves with a herd of wheel-suckers behind us, we ask them to STAY behind us. We'd rather fight the wind ourselves by cranking out a constant effort than be subjected to all that. It's actually easier!

And that is also why tandem specific rallies and rides exist. Because tandems work better with other tandems.

WheresWaldo

You need to ride with more experienced singles!

conspiratemus1

+1.... And by riding with them consistently, you will all gain experience and learn better how to mix it up together with less turbulence. We very much enjoy our little Sunday mixed escadrille.