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High Cadence
 
I'm a "perfectionist" in some aspects...especially with my bikes.

Noticed awhile ago that on our Burley Tosa, the captains crank is about 2-3 teeth/links ahead of the stokers crank. We are getting ready for the riding season, and I'm considering equaling it out.

Other than my knowing that it's not perfectly aligned...is it a big deal? Should we leave it be, or correct it?

Thanks.

I tried the search function, but it's not working today.

Thanks.
Andy and Vickie
(Used to be AndyGrow)

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Wil Davis
 
Some riders set up their tandems with the cranks intentionally out of phase so the power strokes are smoothed out - although in a perfect world, both captain and stoker would have perfect spinning abilities and the pedal strokes would be smooth all the way around…

- Wil

NewbieIATandem
 
I read in the Tandem Book, that you are slightly out of phase in the "right" direction. If it is off by only a couple of teeth you are actually increasing the length of the "power stroke" when you peddle. i.e. You start a bit earlier than the stoker, and the stoker is still peddling a bit after you are on the up-stroke.

I would think if it bothers you, change it, if not, don't.

TandemGeek
 
It means you provide power before your stoker does on each downstroke vs. "sharing" the load 50/50. Some folks will refer to this as riding a few teeth out of phase. Personally, unless you intended to lighten the load on your stoker, I'd loosen the eccentric and get them back in phase before the season starts.

cornucopia72
 
We ride 90 degrees out of phase; the captain leads the stoker. We rode on phase for several years. We found that OOP makes our climbing significantly smother. We stand togheter with no problem. We will not ride on phase anymore. The only drawback is that the captain needs to remember to watch the pedals on thight turns and going over pronounced speed bumps.

zonatandem
 
As stated before: if it does not bother you, not an issue.
Like cornucopia72, we pedal 90 degrees out-of-phase (OOP) and been doing that for over 200,000 miles.
Try it, you might prefer it . . . we did!

Pedal on TWOgether!
Rudy and Kay/zonatandem

Thumbnail of our current tandem with 90 degrees OOP

irablumberg
 
Here is another vote for out of phase with captain ahead of stoker. We don't have that many miles, but after a few hundred in-phase, out-of-phase was a revelation. Everything got smoother, faster and easier overall.

We went on a local 25 mile tandem ride some years ago where we were the only team out of phase and most of the teams were fairly inexperienced. We got looks like we each had an extra head. On the other hand, the terrain was rolling and we powered up the hills and left the other teams behind like they had flat tires.

Ira

transam
 
Interesting discussion of riding out of phase. For those who do, how much OOP works for you? Captain or stoker ahead?

zonatandem
 
Captain's right foot ahead . . . yes, there is also left footed OOP.

cornucopia72
 
We recently bought a triple and yesterday we took it on her maiden voyage. Our daughter took the mid stoker position. In the flats we were in average 2 miles faster... cruising at 23-24, than in our regular tandem. In the triple we rode on phase. Maybe after e few hundred miles we will have enough coruage to try OOP.

ElRey
 
As it takes a few seconds to corerct, why ask?

FoC
 
It means you provide power before your stoker does on each downstroke vs. "sharing" the load 50/50. Some folks will refer to this as riding a few teeth out of phase. Personally, unless you intended to lighten the load on your stoker, I'd loosen the eccentric and get them back in phase before the season starts.
Im fairly mechanically inclined and will be doing 99% of the maintainance on my bike.
Personally there is a bit too much slack in the front chain.
The salesman told me this might need adjusted, and I think I figured out what to loosen in order to make the adjustment, but once Ive loosen the hexbolts, how is the adjustment made.

I can see what needs to be done...but I dont want to make the adjustment until someone tells me if its just getting the eccentric to turn in the desired direction to tighten the chain slightly (its fairly loose)

mrfish
 
It is very simple. Like most things on a bike, even if you don't understand how it works, if you are reasonably mechanically inclined you can take it apart and put it back together again without breaking it, so feel free to experiment. If you're worried, the Park tool website has instructions for most maintenance tasks.

Trsnrtr
 
Getting cranks perfectly in sync can be almost impossible, so I usually end up a half a tooth or so ahead of my stoker.

TandemGeek
 
I can see what needs to be done...but I dont want to make the adjustment until someone tells me if its just getting the eccentric to turn in the desired direction to tighten the chain slightly (its fairly loose)

Sorry, didn't see this until just now....

Yes, it's pretty straight forward: you rotate the eccentric (usually by hand, although a Park Tools Green pin spanner is considered the "proper tool" to use) to take up or reduce the slack in the timing chain. Given that an eccentric is eccentric, knowing whether to rotate forward or backward to remove slack depends on if the crank axle is above or below the centerline of the eccentric.

The only "trick" is to leave enough slack in the chain -- usually an 1" -- before you tighten the eccentric's retention bolts so that you'll still have about 1/2" of slack once everything is snug. Note that, as the eccentric shell (Burley, Co-Motion) or eccentric itself (Trek, Cannondale, Santana) is tightened on a tandem, the axle will usually move forward a bit.

You may find some other useful info here asymetrical timing ring rotation (biopacing), timing ring alignment, etc.: http://www.bikeforums.net/showpost.php?p=1251903&postcount=5

This previous post talks about setting timing chain tension such that you can, if needed, remove your timing chain by hand without loosening the eccentric: http://www.bikeforums.net/showpost.php?p=1410759&postcount=25


Getting cranks perfectly in sync can be almost impossible, so I usually end up a half a tooth or so ahead of my stoker.

See the mid-section of the first linked, previous post where it refers to timing chain alignment.

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