Originally Posted by
commo_soulja
My first mountain bike and bike that I bought with my own money was a 1990 Giant Sedona that was shod with Biopace chainrings. I replaced them within a year for round rings. The pedaling was just weird. Fast forward to 2009-ish and I took a gamble on oval Rotor rings on my Salsa. Way better and smoother power delivery. Shimano could have developed Biopace a little more. I now have two other bikes with oval chainrings - Wolftooth and Absolute Black and they're both great.
Shimano put tons and tons of development effort into Biopace.
Originally Posted by
dsaul
Then someone has clocked them differently than they were intended. In your pic above, the small ring has been clocked one bolt hole off as evidenced by the small tab that should be aligned with the crank arm.
You don't understand a lot of things, but you go on giving advice as if you do. What cadence do you think is efficient? My most efficient cadence is between 93-105rpm for road riding
Thank you for pointing that out..
optimal cadence is dependent on a number of factors. I think past 105RPM means you're in too low of a gear, as it becomes more difficult to efficiently trasnfer power past this stage.
Originally Posted by
icemilkcoffee
A lot of people misunderstand the reason behind the Biopace design. Intuitively you would think you want higher gearing where your leg is strongest (around 3 o'clock), and lower gearing where your leg is weak (12 and 6). If you are seated and grinding at a very low cadence, this is true. However, if you are either standing, or spinning, what ends up happening is that you will typically 'overstomp' 6 o'clock. Meaning you continue to stomp downwards even at or past 6 o'clock. When you are spinning very fast, like going downhill, sometimes you can feel your butt bouncing off the seat with every stroke. This is because you are overstomping 6 o'clock. That wasted energy goes to lifting our butt off the seat. Same with standing and pedaling. A lot of times you have to consciously tell your feet to 'lift up' at 6 because the tendency is to stomp the pedal into the ground. Biopace was designed to counteract this tendency by increasing the resistance when you get close to 6 o'clock.
Of course, Biopace is useless for pro riders who have perfected their circular strokes and never overstomp 6 o'clock. That would be 0.005% of the riding population. The rest of us definitely benefit from the genius of Bio-pace.
So you think that Biopace can be used as a learning tool? Perhaps for switching back to circular chainrings in the future? Or do you think that Biopace is simply superior due to its design?
I would imagine that some types of more serious competition cycling could also benefit from this design.