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  1. #1
    Elite Rider Hermes's Avatar
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    IP versus OOP in Tandem Time Trial Races

    Thighmaster posed a question that got me thinking about IP v OOP in time trials. How do the tandem racers ride? The elite teams are IP. And these teams spare no expense to have the best equipment and in some cases buy and rig tandems just for racing. So tonight, I put the cranks IP and we went on a 30 mile ride with 2000 feet of climbing and an interval session. The ride was inconclusive other than to say that at full power with smooth pedal stroke, I do not see a difference in bike handling or perceived power production (no power meter) and there was no whooshing sound linked to cadence. However, I am suspicious at higher speeds that OOP may have more aero drag due to the out of sych nature of the legs. Last week, I sent an email to the guy that has the tandem simulator in Germany posing the question but I have not received a response.

    Edit: I did observe our acceleration from a standing start was faster IP. This alone can be worth 10 - 20 seconds for the start and turnaround.
    Last edited by Hermes; 06-07-07 at 12:29 AM.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

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    I may get "blasted" for saying this by proponents of OOP... but. I see OOP only being of bennefit for those that are not real smooth with their pedaling.

    As you say these elite racers... will try most anything to go faster. a second here a second there is huge for them. Are they ignorant of OOP? or do they prefer what they are using?

    Yes that time at the start and turn around would be huge. I could see out of phase possibly affecting your drag... but it would be small. I am not sure you could ever measure it without a wind tunnel.

    Perhaps you could do hill coast downs in phase vs OOP.

    I would think all the looking to see who is coming up on you that your stoker is doing would hurt you drag wise... rythm... and focus wise, also.

    Do you use an aerobar?
    good luck... and have fun... thanks for sharing your experiences

    glenn

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    Elite Rider Hermes's Avatar
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    Quote Originally Posted by Fenlason
    As you say these elite racers... will try most anything to go faster. a second here a second there is huge for them. Are they ignorant of OOP? or do they prefer what they are using?

    Perhaps you could do hill coast downs in phase vs OOP.

    Do you use an aerobar?
    The captain of one of the two man teams who won at Dunlap and is the CA state TT Champions belongs to our club. I will ask him but it is only one data point. My hypo is at this level the riders have so much power and optimized pedal stroke, OOP offers no benefit and hurts acceleration which is important in technical TT courses. I doubt that they are ignorant of different phasing setups.

    I did a half baked test last nigh on a couple of down hills using my memory as a protocol for the test and I believed we were faster. It was very windy and the stoker thought it too windy to come to any conclusion. We were clearly not worse.

    Yes we have aerobars and our position needs improvement. I need to get lower but I also need more hamstring flexibility to assure power production in more extreme positions.

    You may be right on the OOP v IP with respect to pedal technique. However, I would say it is more about power production. I have stated this before that more power does wonders for the cycling experience. OOP smooths out and to an extent may optimize the power produced by the team.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

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    Quote Originally Posted by Hermes
    The captain of one of the two man teams who won at Dunlap and is the CA state TT Champions belongs to our club. I will ask him but it is only one data point. My hypo is at this level the riders have so much power and optimized pedal stroke, OOP offers no benefit and hurts acceleration which is important in technical TT courses. I doubt that they are ignorant of different phasing setups.
    I think that most "elite" tandem teams are composed of riders that are at or near an elite level on their singles. If so, it follows that those riders spend as much or more time on their singles as on a tandem. And if you have developed a smooth/quick/comfortable pedal stroke on your single, an OOP tandem feels odd at best, as you experience relatively more resistance than usual on the up/down part of your stroke and relatively less on the fore/aft portion. The result, I think, is decreased power output and accelerated fatigue.

    My theory, then, is that OOP may be "better" for teams that ride only (or mostly) together -- if only because it puts less strain on the drive train. However, IP is the preferred arrangement for teams of cyclists who also spend a significant amount of solo time.

    Whad'ya think?

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    At speed, either cadence or mph, I can't imagine that there would be much difference in performance between IP or OOP.

    I ride OOP because low speed grinding on the local mountains made it difficult to keep the bike in a straight line at less than 4 mph. I've never had an issue, nor seen a difference at cruising speed. My current stoker is getting into shape for the hills and we are not seeing those slow speeds anymore so I may once again go back to IP.

    The idea of aero benefit to one way or the other is interesting. I would guess that there is little difference, the turbulence of the front legs will not have smoothed out by the time the second set of legs hit that spot, I would guess what small benefit there is would go to OOP.

    I am surprised that you found acceleration is better IP. Yes you have two power stokes per revolution that are stronger, but you also have two gaps in power as the teams swings through the dead spots. Of course, a higher cadence minimizes this once you are moving, but i can't get my mind around it. it seems obvious that elimination of that dead spot with OOP would come into play until you got the cadence up.

    Racing is an interesting thing, rules often come into play to 'keep it fair' or 'level the playing field. If there is no rule against OOP, what is the history of tandem racing. At one time was OOP in favor, then a well trained IP team came along and cleaned up? Or has IP the only thing thats been done, or allowed. i don't know, just wondering out loud.

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    Elite Rider Hermes's Avatar
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    Quote Originally Posted by bikeriderdave
    I think that most "elite" tandem teams are composed of riders that are at or near an elite level on their singles. If so, it follows that those riders spend as much or more time on their singles as on a tandem. And if you have developed a smooth/quick/comfortable pedal stroke on your single, an OOP tandem feels odd at best, as you experience relatively more resistance than usual on the up/down part of your stroke and relatively less on the fore/aft portion. The result, I think, is decreased power output and accelerated fatigue.

    My theory, then, is that OOP may be "better" for teams that ride only (or mostly) together -- if only because it puts less strain on the drive train. However, IP is the preferred arrangement for teams of cyclists who also spend a significant amount of solo time.

    Whad'ya think?
    We spend 50/50 riding tandem and single. We race the tandem because it is fun and it adds another dimension to the sport. Next year, we will race singles. We have spent the last year working on smooth pedal stroke on both the singles and tandem. We really like OOP stoker leading for standing and hill climbing and it is very smooth, easy on the equipment and always a conversation piece. However, your theory of the lack of training together on the bike may be valid. It would be easier to throw together and IP team - maybe. But if they thought that there is an advantage to OOP, you can bet racers would put in a couple more practice sessions.

    At Sunday's TT, we will be IP. Why...conformity. I cannot confirm or deny IP v OOP aero advantage so for a 40K TT we will conform and make sure we do not give up anything to an already very tough field.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

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    slightly off topic, but if you want to get lower and your hamsting flexibility is an issue, then try sliding your saddle as far forward on the rails or a 'fast forward' triathlon seatpost which has now setback (you might even get way with rotating your current one if the angle adjustment allows, then you effectively can rotate your body down, while retaining the hip angle that gives you good power. You can also sit right on the nose of the saddle.

  8. #8
    Elite Rider Hermes's Avatar
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    Quote Originally Posted by specialist
    slightly off topic, but if you want to get lower and your hamsting flexibility is an issue, then try sliding your saddle as far forward on the rails or a 'fast forward' triathlon seatpost which has now setback (you might even get way with rotating your current one if the angle adjustment allows, then you effectively can rotate your body down, while retaining the hip angle that gives you good power. You can also sit right on the nose of the saddle.
    Thanks for the tip. I will check it out.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

  9. #9
    Senior Member zonatandem's Avatar
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    In our 32+ years and 200,000+ miles of riding as a tandem duo we've never considered ourselves either experts/elite riders, but settled on the term 'experienced.'
    We were mostly into day rides, centuries, multi-day distance events and did get in a few TTs and some track riding. All of it done OOP.
    Our approach to tandem TTs was: both of us in the drops, elbows in and hammer. Geared back for the start for easy take-off and then get into a bigger gear we could comfortably handle, depending on conditions.
    The least aero part in a time trial is a person(s) body; our very short wheelbase tandem possibly gave a bit more aero advantage, while pedaling OOP possibly gave us a minor disadvantage.
    Never enough for us to worry over it.
    Nice to see that tandem TTs are happening. Go for it!

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    Elite Rider Hermes's Avatar
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    Quote Originally Posted by zonatandem
    In our 32+ years and 200,000+ miles of riding as a tandem duo we've never considered ourselves either experts/elite riders, but settled on the term 'experienced.'
    We were mostly into day rides, centuries, multi-day distance events and did get in a few TTs and some track riding. All of it done OOP.
    Our approach to tandem TTs was: both of us in the drops, elbows in and hammer. Geared back for the start for easy take-off and then get into a bigger gear we could comfortably handle, depending on conditions.
    The least aero part in a time trial is a person(s) body; our very short wheelbase tandem possibly gave a bit more aero advantage, while pedaling OOP possibly gave us a minor disadvantage.
    Never enough for us to worry over it.
    Nice to see that tandem TTs are happening. Go for it!
    FYI...here is your Zona tandem in action...http://www.hcphoto.smugmug.com/galle...55382/Original Check out the wheelset. Carbon bladed spokes.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

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    hors category TandemGeek's Avatar
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    Quote Originally Posted by bikeriderdave
    My theory, then, is that OOP may be "better" for teams that ride only (or mostly) together -- if only because it puts less strain on the drive train. However, IP is the preferred arrangement for teams of cyclists who also spend a significant amount of solo time.

    Whad'ya think?
    I think what you've got there is conjecture, not a theory. But thanks for playing...
    Last edited by TandemGeek; 06-07-07 at 06:27 PM.

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    Theory, conjecture... call it what you will.
    Hermes observed that the fast teams ride IP and wondered if there is some logical, explainable, measurable performance advantage to the arrangement. The implied assumption is that elite teams ride IP because it is inherently faster. But I suspect that it's the other way around: IP is faster because the best riders prefer it. Why do they prefer it? Probably because, when tried briefly, OOP feels odd/awkward to experienced (single) cyclists. Zonatandem and others suggest that OOP is better once a team acclimates. But in the absence of real evidence and incentive (imagine a parallel universe in which an OOP team dominates high profile tandem races that bestow real prizes and prestige on the victors), almost all accomplished cyclists will continue to ride IP when they add tandeming to their range of cycling activities.
    My (unsolicited) advice to Hermes: If you want to win tandem TTs, first become riders who can win individual TTs. It won't really matter then if you ride in or out of phase.

  13. #13
    Senior Member zonatandem's Avatar
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    Good lookin' Zona TT team! Are those Topolino wheels?
    As far as IP/OOP goes, we know we have been in the minority for decades as OOPers, but hey, we like it!
    Pedal on TWOgether!
    Rudy and Kay/zonatandem

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    Elite Rider Hermes's Avatar
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    Quote Originally Posted by zonatandem
    Good lookin' Zona TT team! Are those Topolino wheels?
    As far as IP/OOP goes, we know we have been in the minority for decades as OOPers, but hey, we like it!
    Pedal on TWOgether!
    Rudy and Kay/zonatandem
    Yes...pretty cool.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

  15. #15
    Senior Member zonatandem's Avatar
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    Topolino just debuted their tandem specific wheelset at Interbike last fall and said they'd be up for sale in 2007.
    Have a pair on my single: light/sturdy/comfortable ride. Unique spokes and spoke setup. 24 spokes front and 30 spokes rear. Rear has 18 on the drive side and 12 on opposite side. Did use Topo front wheel on our tandem for test ride. No problems.
    A couple years ago at Interbike, Craig Calfee showed off one of his tandems with the then new Topo single bike wheels. He re-spaced the rear hub and mentioned he had a couple really tough test riders that destroyed most wheelsets he had tried, but the Topos had 5,000+ miles on them, without any issues.
    So Craig and us bent the ears of the Topolino folks for a couple years trying to get them to build a tanderm specific wheelset. Looks like our request has been fullfilled!
    Another great choice for folks who want/need a super wheelset!
    Pedal on TWOgether!
    Rudy and Kay/zonatandem

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    Senior Member Velodiva's Avatar
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    Quote Originally Posted by Fenlason
    I would think all the looking to see who is coming up on you that your stoker is doing would hurt you drag wise... rythm... and focus wise, also.
    glenn
    That is just Hermes' dramatic storytelling.
    In bocca al lupo!

  17. #17
    Senior Member zonatandem's Avatar
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    Found out the Schotte Zona TT tandem has 130mm rear spacing, so a standard Topolino road wheel set was used, not the new tandem specific.

  18. #18
    Don't mince words Red Rider's Avatar
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    Quote Originally Posted by Velodiva
    That is just Hermes' dramatic storytelling.
    Dramatic but effective. Why, I actually imagined I was there myself (on your bike, not mine).

    Your peripheral vision works just fine, doesn't it?
    When my feet hit the floor in the morning, Satan shudders and says, "Oh, *****, she's awake!"

    Visit my blog.

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    Quote Originally Posted by Velodiva
    That is just Hermes' dramatic storytelling.

    I was just trying to pass on a possible tip.

  20. #20
    Elite Rider Hermes's Avatar
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    Quote Originally Posted by zonatandem
    Found out the Schotte Zona TT tandem has 130mm rear spacing, so a standard Topolino road wheel set was used, not the new tandem specific.
    Today at the 40K TT at Sattley, he used Zipps - same team.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

  21. #21
    Senior Member Velodiva's Avatar
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    Quote Originally Posted by Red Rider
    Your peripheral vision works just fine, doesn't it?
    Absolutely, and a sixth sense that stokers develop that detects another tandem approaching from behind.
    In bocca al lupo!

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