Offset Cranks

Sounds like THIS is what you're referring too:

http://www.rotorcranksusa.com/whatis.htm

Looks like it's a good theory, but then so were Biopace chainrings.

Hey!I found this one, this look really really interesting.

The name is Rotor Cranks, it is supposed to eliminate the "dead spot" of the top pedal. See the animation it explains a lot. http://www.rotorcranksusa.com/whatis.htmInthe front page is the list of allll the triathletes and cyclist who use it.

Looks interesting but the price is a bit high, $693 for the road double steel and $927 for the road double titanium :S

Edit: Damn you guys are fast!

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Wow, very interesting.  I biopace came and went rather quickly...but those had an eggshaped chainring so perhaps this idea is better....

I love change and would be all about trying this.  Obviously, I'll ask the coach to see what his thoughts are before doing anything rash.

Here's this millenium's version of the Biopace:

http://www.velonews.com/tech/report/articles/6807.0.html

After reviewing the site, it all looks very reasonable (except for the price).  I wonder how much more it weighs than a typical fixed crank.  If you're doing a long bike in a tri, say 56 or 112 miles, this sounds like it would really be very helpful, especially when on hilly courses.

Also, if you delete the chainrings on your order, it reduces the price significantly.  So, I have two questions...are all chainrings interchangable with any crank?  Would my Shimano rings fit on this thing?  Also, it asks what kind of bottom bracket you have, BSA or Italian.  I presume the Italian refers to Campy and will dictate which way the crank arms are threaded, is that correct?

See the site's FAQ for a discussion on BSA vs Italian.

Per the website, the titanium crankset weighs 380 grams (about 13.4 ounces) more than Dura Ace.

Haven't seen if it's compatible with standard Shimano chainrings, but you can ask.

So, are you ordering a set, Karl?

No, not ordering them just yet.  I also looked into those Osymetric chain rings.  They cost considerably less and seem to accomplish the same basic function.  Check out the site....

http://www.osymetric.com/pricelist.htm

I am thinking about ordering a set of these to see how they work.  However, it would seem that when the chain is on the "thin" side of the chainring, that there might be some additional slack that could cause it to slip off, especially if you were making gear changes at just the wrong time.  But, if Ulrich swears by them in competition, I suppose they can't be all bad.

Those rotor cranks worry me since they're mechanical and have internal moving parts.  Plus, they add nearly an extra pound to the weight of the bike.

What's a pound among friends?

Of course it would!  I could only be so lucky!

Hey...someone had to do it!  it was there...it had to be said!!!

"Another pound of crank won't even be noticed"  - I bet if I asked Mother Bear, she might have another opinion (did I just say that out loud?)

John, I hear you...I, too am 15lbs heavier than my end of the season weight last year.  I don't notice it on the bike or swim so much, but I sure feel those lbs when I'm running.  I just visualize a 10lb and 5lb plate strapped to my back and it really motivates me to lose this weight and soon!

So, what do you think about these Osymetric chain rings?

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Not necessarily.  One revolution is still one revolution.  The cam makes the push stroke longer and the pull stroke shorter, but you still complete a 360 degree revolution with each leg nonetheless.

Just got the nix from the coach on this contraption.  Sounds like your pedal stroke will end up getting a pretty heavy dead spot after using this chainring for a while.

I like your thinking, Angie....