Biopace Chainrings
Bikes June 20th, 2007
All due respect to Sheldon Brown, but I cannot believe that anyone can talk about BioPace chainrings as anything other than utter fucking filth. This is like lauding the brilliance of the Citroen hydropneumatic ball based engine stuff, or how great an idea it was to use nikasil-liners, how the Titanic design was truly brilliant, the Hindenberg was amazingly well thought out. The simple fact is, history has god damned spoken, and time and time again, the results are the same. Piece of shit. Officially disavowed by the people who made it, universally accepted as failures. Moderate fowardthink without any real analysis. Maths without fizzix. But every couple months, on the ONE cycling forum I read, there are five pages of huffing and puffing about how it was OK and how it was really a pretty good idea, etc.
That’s dumb. If you think Biopace is good, you have dumbness in you.
Biopace has real advantages, one of which is that it is kinder to my knees. http://sheldonbrown.com/biopace
I must admit a fondness for Citröens, always lusted for a DS, but never crazy enough to buy one. If I lived in France I probably would. French friends tell me they’re not all that difficult to work on once you know their peculiarities.
The Hindenberg was a great airship, designed for helium flotation. With helium it would have been probably the safest way to cross the Atlantic, but the U.S. government forbade the sale of helium to the Zeppelin company, so they had to use dangerous hydrogen.
I have no idea what nikasil liners might be, and no defense for the Titanic.
Sheldon “Dumb” Brown
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| When anyone asks me how I can best describe my experience |
| in nearly 40 years at sea, I merely say, “uneventful.” |
| Of course, there have been many gales and storms and fog |
| and the like. But in all my experience, I have never been |
| in any accident of any sort worth speaking about. I have |
| never seen but one vessel in distress in all my years at sea. |
| I never saw a wreck and never have been wrecked, nor was I |
| ever in any predicament that threatened to end in disaster |
| of any sort. –E. J. Smith, Captain, RMS Titanic |
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An excellent defense all the way around, but I think we’re going to have to agree to disagree. I’ve seen a great many arguments for Biopace that frequently come down to “feel” or “comfort”, which are difficult to quantify and by definition subjective. My biopace chainwheels caused me nothing but problems, specifically long lasting and cumulative knee pain that was not present prior to my switch to biopace and that relented after my (and much of the worlds) hasty retreat from the technology.
Nikasil liners were a cylinder wall treatment put into some BMWs and assorted other european cars that reacted unfavorably to sulphur. More here - http://en.wikipedia.org/wiki/Nikasil - A novel thoeretical solution to a very real problem that ended poorly because of a lack of testing. Replaced by Alusil - http://en.wikipedia.org/wiki/Alusil - once the problem was discovered.
When I was in France, there was a Citroen 2CV Truck in the bus station parking lot of the Avignon train station for 300 euros. If I could have thought of a way to get it home (and eliminate the novelty spheres), I would almost certainly have purchased it. The shifter went horizontally into the dash and had a shift pattern that may have moved in some unseen fourth dimension, and it was cute as a button.
As far as the Hindenberg, I understand the helium/hydrogen sales issue, but frankly, if someone told me I couldn’t get regular gasoline for my car, but they could rig it to run on a couple bumper mounted tanks of acetylene, I’d probably try to find somebody else to sell me gasoline. Again, an engineers over implementation issue. Hydrogen could certainly lift the craft, but obviously, the “could we catch on fire” question wasn’t explored enough.
The Titanic suffered much this same fate, as I think even a scale model, properly tested, would have indicated the logical flaws of the design, but it sounded good in the mouth.
PS - Sorry to hear about the legs. I read your journal often and it is a source of great amusement.
I’ve had a Raleigh Randoneur touring bike that I’ve ridden since about 1990. When I was riding through South East Asia in 1992, I stopped in Singapore and replaced the worn out original crankset with a Shimano biopace set, which I have had ever since.
Subsequently I’ve done thousands and thousands of miles on that biopace crankset and never had any significant knee problems.
I would happily buy another biopace crankset tomorrow, if only they were available.
I doubt whether the first commenter has ever even used biopace. Sounds like he’s just regurgitating something he’s picked up on the web somewhere
In the early 90s, biopace was all the rage, until it suddenly fell from grace. Funny how so many cycle magazine editors were all in favour of it for a year or two, then all suddenly changed their minds again
Everything goes in cycles (pardon the pun) and it’s my prediction that biopace (under a different name of course), will make a come back 10, 15 or 20 years down the line (by which time the first commenter might hopefully have managed to have calmed himself down a bit)
I owned a KHS mountain bike with eliptical chainwheels for 16 years without an adverse incident and no knee pains. As a physician, I suspect that there are other anatomic and mechanical forces at work here that vary from one individual to another and may determine whether or not knee problems will result from any particular design.
I think that’s a fair bet. No doubt that if I wore another man’s orthopedic inserts (especially if they’re correcting an extreme condition) I’d end up with foot pain (if not lower back pain). However, I’m gonna guestimate that 99% of all bikes were made with traditional round chainrings, much like 99% of shoes ever made were created with a non-prescription (or noncustom) footbed. So I stick with my assertion that we standardized on round chainrings for good reason(s).
Oh, and to the commenter who is vaguely implying that my problems with biopace are related to my undying love of magazine editors or whatever, fuck you! Have a good one.
I wore out two sets of SS biopace chainrings over the course of many thousands of miles on mountain bikes.
Never once did my knees bother me, although others told me of their issues with them.
I suspect my style of riding had much to do with my liking them, seat low, BMX style.
As Sheldon said on his site, they worked very well for getting power to the ground and not spinning the rear wheel in a high torque, low speed situation.
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“Though force can protect in emergency, only justice, fairness, consideration and co-operation can finally lead men to the dawn of eternal peace”
Dwight D. Eisenhower
This is the single most read entry in my blog, hands down. I still think biopace chainrings are dumb. I do tend to keep my saddle somewhat higher than others might. I haven’t ever been comfortable on a BMX, or actually on any bike that keeps the legs bent and the hips rotated (cruiser bikes, even a traditional long wheelbase recumbent I found to be fairly bothersome).
I have been working on and off on a cruiser/townie style bike that is more to my liking, hips/legs/knees in the standard cycling position (actually, it’s a little more relaxed than my normal fare, partially because it’s an MTB frame and partially because it’s got too long of a fork on it, fuxoring all the angles). It is pretty. I should take more pictures of it now with it’s proper parts on.