[hortan]

I was wandering: wouldn't it be better to 'offphase' the front- and rear tandem cranks by a 90 degrees angle? I would expect a less peak load of the chain(wheels) and sprockets and a more smooth speed. On the other side perhaps there would arise more torsion stresses in our frame. Is it to be expected that in the end our frame (Aluminium!) would collapse due to fatique?
Who has experimented between in phase and 90 degr. off phase?

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[transam]

We have been experimenting with out of phase (OOP) cranks for two weeks now and simply love it. Started with 45 degrees, then increased to 60 for a few days and are now riding at 90. Captain has been lead crank in all cases. The results have been amazing. Our average speed has increased in all cases, climbing has significantly improved and the pedal stroke is much smoother.

Cornering is a concern for some when riding OOP, but we have not had any problems - never come close to hitting a pedal. We quite often stand to ride and are still able to do so, even both at the same time. Our suspicions are that there is less torque on our frame (aluminum) and less pressure on the components when shifting - time will tell on these matters.

You will be hard pressed to find other OOP riders when you do group rides. We have yet to see one. All the feedback we've received has been right here on the BikeForums. Our thoughts are that so few do it because they are concerned with how it looks to others, but when you are trying to keep up in a group ride or climbing a long grade those looks don't matter. We will continue to ride OOP and enjoy the benefits. Try it you may like it.

[zonatandem]

We have been riding OOP for over two hundred thousand tandem miles; tried it back in 1977 after 2 years of riding in-phase.
Benefits: there is always a power stroke going 'over the top.' Less twisting (torque) on the frame . . . picture 2 people pushing hard with left foot, then hard with right foot when pedaling 'in-phase'.
Watch them climbing a hill and you'll see what is referred to as 'tandem snake' . . . the back end of the tandem 'waggles' with each hard pedal stroke. Pedaling OOP minimizes tandem snake/frame stress.
Easier climbing, easier/faster 'get away' starts from traffic lights/stops.
Actually less stress on components and frame. For a brief time in the early 80s Santana recommended that their tandems be set up OOP, but somehow that idea didn't sell any more tandems.

Drawbacks: Leaning hard into a corner you *could* clip a pedal into the pavement; however, most tandemers don't lay a racing corner at high speed.
You also *could* hit a pedal when crossing over the old fashioned high apex speed bumps.
A bit more difficult for both pilot and stoker to stand simultaneously.
It doesn't look *cool*.

Note: Normal OOP setup is with captain's pedal leading (either left or right foot, you preference). Most folks prefer 90 degrees OOP although, again, your preference . . . you can pedal a couple teeth OOP or all the way to 180 degrees. Agree with transam,there's not too many OOPers out there!
As far as an alu frame (or steel, or ti or cabon) 'collapsing' from riding OOP . . . We've owned 4 tandems that we put 50,000+ miles on riding OOP.
As stated before: try it, you may like it! We do!!!

Pedal on TWOgewther!
Rudy and Kay/zonatandem

[lmzimmer]

We have been riding 90 degrees out of phase for about the last 10 months- We took Zona tandems recommendation from an earlier phase( Thanks Rudy) . The plan was to try it a month and then go back to see which we liked better. Never felt the need to go back. Starting took a few days to feel right but now it is second nature. Standing is still a work in progress, but I actually think standing together works better oop than in phase due to less weight shift as well as the other reasons mentioned. That being said we do a lot of sequential standing where one person stnds till they have had enough then the other alternates- this has not changed much .We have never had problems with cliping pedals in cornering- just our style again. - Mark

[lmzimmer]

Oh, by the way, I read a post from another team captain recently- I am not sure if it was on this forum or T@hobbes- but they had a poor ride and felt it was related to inadvertantly having slipped a few cogs out of
phase. I personally doubt that most people would know except for when they first started. Some rides are better than others- I never know what to blame the off ones on:rolleyes: http://www.bikeforums.net/images/smilies/rolleyes.gif Mark

[hortan]

Hi folks transam,zonatandem and imzimmer thanks for sharing your experiences on this matter. This afternoon we made our very first ride on our (first but 2nd hand) tandem. We bought it a couple of weeks ago but I wanted to adjust some things first, like the 90 degrees out of phase cranks amongst other changes. So we even didn’t try for the ‘inphase’ option because I disliked it theoretically and you were all unanymous that also practically there are many adventages and no drawbacks ! And really I agree with you all :I like it and we will not even try the standard position!
Smooth ride, less dead point at traffic lights, no torsion felt in the frame and so on.
By the way: wish I knew (20 years ago) what I know now: we would have bought a tandem long ago !