Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Tandem Cycling A bicycle built for two. Want to find out more about this wonderful world of tandems? Check out this forum to talk with other tandem enthusiasts. Captains and stokers welcome!

User Tag List

Reply
 
Thread Tools Search this Thread
Old 06-07-07, 12:23 AM   #1
Hermes 
Elite Rider
Thread Starter
 
Hermes's Avatar
 
Join Date: Oct 2006
Location: La Jolla, CA
Bikes: Too Many
Posts: 9,914
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
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.
__________________
Insanity: doing the same thing over and over again and expecting different results. Albert Einstein

Last edited by Hermes; 06-07-07 at 12:29 AM.
Hermes is offline   Reply With Quote
Old 06-07-07, 05:17 AM   #2
Fenlason
Senior Member
 
Join Date: Jan 2007
Location: Central Maine
Bikes:
Posts: 156
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
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
Fenlason is offline   Reply With Quote
Old 06-07-07, 07:38 AM   #3
Hermes 
Elite Rider
Thread Starter
 
Hermes's Avatar
 
Join Date: Oct 2006
Location: La Jolla, CA
Bikes: Too Many
Posts: 9,914
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
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. Albert Einstein
Hermes is offline   Reply With Quote
Old 06-07-07, 12:18 PM   #4
bikeriderdave
Cyclist
 
Join Date: Apr 2004
Location: Wisconsin, USA
Bikes:
Posts: 166
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
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?
bikeriderdave is offline   Reply With Quote
Old 06-07-07, 12:50 PM   #5
cfblue
Senior Member
 
Join Date: Apr 2007
Location: San Francisco north bay
Bikes:
Posts: 73
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
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.
cfblue is offline   Reply With Quote
Old 06-07-07, 12:54 PM   #6
Hermes 
Elite Rider
Thread Starter
 
Hermes's Avatar
 
Join Date: Oct 2006
Location: La Jolla, CA
Bikes: Too Many
Posts: 9,914
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
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. Albert Einstein
Hermes is offline   Reply With Quote
Old 06-07-07, 03:42 PM   #7
specialist
Member
 
Join Date: Nov 2006
Bikes:
Posts: 25
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
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.
specialist is offline   Reply With Quote
Old 06-07-07, 04:02 PM   #8
Hermes 
Elite Rider
Thread Starter
 
Hermes's Avatar
 
Join Date: Oct 2006
Location: La Jolla, CA
Bikes: Too Many
Posts: 9,914
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
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. Albert Einstein
Hermes is offline   Reply With Quote
Old 06-07-07, 04:06 PM   #9
zonatandem
Senior Member
 
zonatandem's Avatar
 
Join Date: Dec 2003
Location: Tucson, AZ
Bikes: Custom Zona c/f tandem + Scott Plasma single
Posts: 10,904
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
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!
zonatandem is offline   Reply With Quote
Old 06-07-07, 04:27 PM   #10
Hermes 
Elite Rider
Thread Starter
 
Hermes's Avatar
 
Join Date: Oct 2006
Location: La Jolla, CA
Bikes: Too Many
Posts: 9,914
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
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. Albert Einstein
Hermes is offline   Reply With Quote
Old 06-07-07, 06:12 PM   #11
TandemGeek
hors category
 
TandemGeek's Avatar
 
Join Date: Jan 2002
Bikes:
Posts: 7,213
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
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.
TandemGeek is offline   Reply With Quote
Old 06-08-07, 08:23 AM   #12
bikeriderdave
Cyclist
 
Join Date: Apr 2004
Location: Wisconsin, USA
Bikes:
Posts: 166
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
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.
bikeriderdave is offline   Reply With Quote
Old 06-08-07, 11:06 AM   #13
zonatandem
Senior Member
 
zonatandem's Avatar
 
Join Date: Dec 2003
Location: Tucson, AZ
Bikes: Custom Zona c/f tandem + Scott Plasma single
Posts: 10,904
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
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
zonatandem is offline   Reply With Quote
Old 06-08-07, 01:20 PM   #14
Hermes 
Elite Rider
Thread Starter
 
Hermes's Avatar
 
Join Date: Oct 2006
Location: La Jolla, CA
Bikes: Too Many
Posts: 9,914
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
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. Albert Einstein
Hermes is offline   Reply With Quote
Old 06-08-07, 01:38 PM   #15
zonatandem
Senior Member
 
zonatandem's Avatar
 
Join Date: Dec 2003
Location: Tucson, AZ
Bikes: Custom Zona c/f tandem + Scott Plasma single
Posts: 10,904
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
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
zonatandem is offline   Reply With Quote
Old 06-08-07, 11:45 PM   #16
Velodiva
Senior Member
 
Velodiva's Avatar
 
Join Date: Dec 2006
Location: Peninsula, N. CA.
Bikes: Orbea Orca - 2007, Orbea Ordu - 2008, Cervelo P3 track, Santana Sovereign tandem
Posts: 542
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
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.
Velodiva is offline   Reply With Quote
Old 06-09-07, 08:48 PM   #17
zonatandem
Senior Member
 
zonatandem's Avatar
 
Join Date: Dec 2003
Location: Tucson, AZ
Bikes: Custom Zona c/f tandem + Scott Plasma single
Posts: 10,904
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
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.
zonatandem is offline   Reply With Quote
Old 06-09-07, 08:55 PM   #18
Red Rider
Don't mince words
 
Red Rider's Avatar
 
Join Date: Jan 2007
Location: Vacaville, CA
Bikes: '16 BH Quartz, Co-Motion Roadster "Blue Jay"; Fuji D6 TT bike
Posts: 6,955
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
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?
Red Rider is offline   Reply With Quote
Old 06-10-07, 06:27 AM   #19
Fenlason
Senior Member
 
Join Date: Jan 2007
Location: Central Maine
Bikes:
Posts: 156
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Velodiva
That is just Hermes' dramatic storytelling.

I was just trying to pass on a possible tip.
Fenlason is offline   Reply With Quote
Old 06-10-07, 09:29 PM   #20
Hermes 
Elite Rider
Thread Starter
 
Hermes's Avatar
 
Join Date: Oct 2006
Location: La Jolla, CA
Bikes: Too Many
Posts: 9,914
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
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. Albert Einstein
Hermes is offline   Reply With Quote
Old 06-11-07, 10:14 PM   #21
Velodiva
Senior Member
 
Velodiva's Avatar
 
Join Date: Dec 2006
Location: Peninsula, N. CA.
Bikes: Orbea Orca - 2007, Orbea Ordu - 2008, Cervelo P3 track, Santana Sovereign tandem
Posts: 542
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
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.
Velodiva is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 09:30 PM.