Oval vs round chain rings?

[clubby]

Hate oval. Especially on low speed.

Which one, there's a massive variation in concepts (and execution).

The Osymetric ones made me feel seasick......

Exactly. Modern evangelists say that the Biopace oval was on the wrong timing of the power stroke. These days the oval is clocked 90deg to what it used to be. Very different degrees of ovality as well.
TBH I tried one and swapped it out again after a few weeks. I have a few different bikes and the first half hour of every ride felt weird if I’d ridden one of the others in between. Couldn’t feel any magical benefit either.

Try it out but give it a few rides just to get used to the difference.

 

[greencat]

Biopace borked my knees, and round rings fixed it straight away. But I did spin a very high cadence back then.

 

[ishaw]

Re:

Cool, I assume it is fitted the right way, in fact it can't go any other way due to the weird modern bcd of the xt cranks. Its a oneup version in 30t. Not been that low on the tooth count before. I think the xt cassette is 46t.

 

[drystonepaul]

Re:

I run Absolute Black oval chainrings on two of my road bikes including my Kinesis Gf-ti which is my main Audax bike.

The first time I used them was on a 200km solo Audax and I was immediately impressed with the noticeable benefits when climbing in lower gears.
The oval design really reduces the dead spot in the pedalling stroke so you don't have a high resistance point to overcome.
It kind of feels like your leading foot is already falling into the power stroke each time you get just past the 12 o clock position.
It's a bit difficult to articulate.

It makes accelerating your cadence much easier and feels as though you are turning a slightly lower gear.

The most tangible benefit for me was that for the first time in a long time I had a ride without any knee pain, which is something that has reoccured for many years.

I've probably done over 10000km on AB oval chainrings now including several 200km rides, a few 300s, a 400 and a 600km last September.

I'm definitely an advocate.

 

[Matthews]

I'm a was very sceptical as I remember biopace, tried one and love it , smooths out power delivery , still have a bike with rounds and feels jerky when I ride it , I'll be sticking with the egg from now on .

 

[ishaw]

Re:

Not had a chance to build my bike up yet. Tonight I managed to rebuild the forks and increase the travel as the new air shaft arrived today.

Hopefully I should be able to build it up over the weekend if some remaining parts arrive.

Looking forward to giving it a go along with some other new (to me) fangled tech.