Shimano Biopace and other "non-round Chainrings"
#1
Member
Thread Starter
Join Date: Aug 2012
Location: Arkansas River Valley
Posts: 28
Bikes: 1984-88? Huffy TechtraLITE
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Shimano Biopace and other "non-round Chainrings"
I ran across this on the interwebs while looking into the Q-rings. This is, as far as I can tell, the only scientific study on the subject of non-round chainrings.
I searched the forum for "Biopace", but it returned a bunch of threads that only refereed to it in passing, and I could not find one that was just for elliptical chainrings. If there is one, let me know, and I will move the link there.
What are your experiences with biopace and other elliptical chainrings? Do you love them? Hate them? Want to try them? Any shifting problems?
https://www.noncircularchainring.be/p...elease%202.pdf
I searched the forum for "Biopace", but it returned a bunch of threads that only refereed to it in passing, and I could not find one that was just for elliptical chainrings. If there is one, let me know, and I will move the link there.
What are your experiences with biopace and other elliptical chainrings? Do you love them? Hate them? Want to try them? Any shifting problems?
https://www.noncircularchainring.be/p...elease%202.pdf
#2
十人十色
None of the above but I did notice that most riders in the time trial and track events in the London Olympics seemed to be using elliptical rings...
#3
Senior Member
Join Date: Mar 2012
Location: santa barbara CA
Posts: 1,087
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 96 Post(s)
Liked 30 Times
in
21 Posts
Biopace, a very subjective topic. "Bad for knees, knees not effected, not good for high cadence, doesn't effect cadence" etc. I used to ride them in the 80s, don't remember any issues with them, probably changed them because they went out of style. I do have some biopace rings, I may install them and see what I think now, I'm guessing for the riding I do it won't make a difference. If you have some give them a try and see how they ride for you. Lots of 80s mtb were spec'ed with them and they are easy and cheap to find. I guess some folks think they look dorky and change them for that reason, but probably not as many C&Vers are concerned with the dorkiness factor as other segments of the cycling community. Oh yeah, the biopace rings need to be mounted in a specific relationship to the cranks, but I can't recall off the top of my head what it is. If you get/try some let us know what you think.
Brian
Brian
Last edited by calstar; 08-29-12 at 09:21 AM.
#4
Senior Member
Join Date: Sep 2011
Location: middle north (Mpls)
Posts: 216
Bikes: some
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I've had them both, and jumped back and forth from a bike with and a bike without the Biopace rings. I could tell very little, if any difference. At my performance level(low) I don't think it really matters.
#6
Member
Thread Starter
Join Date: Aug 2012
Location: Arkansas River Valley
Posts: 28
Bikes: 1984-88? Huffy TechtraLITE
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Frantik, I know, I was surprised to find that none are really that much better than round.
I have some Biopace on a diamondback topanga that I am in the process of building. I can not wait to try it out, but was interested to find this paper on the matter.
I have some Biopace on a diamondback topanga that I am in the process of building. I can not wait to try it out, but was interested to find this paper on the matter.
#7
Ellensburg, WA
Join Date: Aug 2008
Location: Ellensburg, WA
Posts: 3,755
Bikes: See my signature
Mentioned: 77 Post(s)
Tagged: 0 Thread(s)
Quoted: 313 Post(s)
Liked 458 Times
in
160 Posts
I have several different Biopace rings (all steel so I haven't used them) and some SR Sakae Oval Tech rings that also haven't gone on a bike. I'm working on a Peugeot hybrid right now and am planning on doing a radical 48-28 set up with some alloy Stronglight BioStrong rings. I pulled these out of a box at the LBS at no charge and have been waiting for something to put them on. The middle ring was unfortunately missing which is why I'm going to try it with what I have. Just riding it on the road in the very eliptical small ring I don't notice much of a difference.
__________________
1984 Gitane Tour de France; 1968 Peugeot PL8; 1982 Nishiki Marina 12; 1984 Peugeot PSV; 1993 Trek 950 mtb; 1983 Vitus 979; Colnago Super, mid-80's Bianchi Veloce, 1984 or 85 Vitus 979
1984 Gitane Tour de France; 1968 Peugeot PL8; 1982 Nishiki Marina 12; 1984 Peugeot PSV; 1993 Trek 950 mtb; 1983 Vitus 979; Colnago Super, mid-80's Bianchi Veloce, 1984 or 85 Vitus 979
#8
Member
Thread Starter
Join Date: Aug 2012
Location: Arkansas River Valley
Posts: 28
Bikes: 1984-88? Huffy TechtraLITE
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
#9
Chainstay Brake Mafia
Join Date: Mar 2011
Location: California
Posts: 6,007
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Likes: 0
Liked 11 Times
in
10 Posts
It's funny that biopace is the only one that is worse. I wish they had data on the other makes of biopace and had tried to find an "optimal" position. I was contemplating experimenting with putting a biopace ring on a pedicab to see if it would save my knees at all, but now I definitely will NOT be doing that :-p
#10
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,629
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3871 Post(s)
Liked 2,568 Times
in
1,579 Posts
I threw a set onto my Bianchi FOR the dorkiness factor.
The idea behind Biopace (as I understand it) was to ease stress on your knees, which means putting the "large" portion of the ring 90 degrees out of phase from where it would help deliver more leverage, since momentum needs to be considered. I haven't noticed a huge difference either way -- the main thing for me is to remember to spin small gears rather than to mash big ones.
The idea behind Biopace (as I understand it) was to ease stress on your knees, which means putting the "large" portion of the ring 90 degrees out of phase from where it would help deliver more leverage, since momentum needs to be considered. I haven't noticed a huge difference either way -- the main thing for me is to remember to spin small gears rather than to mash big ones.
#11
Member
Thread Starter
Join Date: Aug 2012
Location: Arkansas River Valley
Posts: 28
Bikes: 1984-88? Huffy TechtraLITE
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
It's funny that biopace is the only one that is worse. I wish they had data on the other makes of biopace and had tried to find an "optimal" position. I was contemplating experimenting with putting a biopace ring on a pedicab to see if it would save my knees at all, but now I definitely will NOT be doing that :-p
#12
Member
Thread Starter
Join Date: Aug 2012
Location: Arkansas River Valley
Posts: 28
Bikes: 1984-88? Huffy TechtraLITE
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The idea behind Biopace (as I understand it) was to ease stress on your knees, which means putting the "large" portion of the ring 90 degrees out of phase from where it would help deliver more leverage, since momentum needs to be considered. I haven't noticed a huge difference either way -- the main thing for me is to remember to spin small gears rather than to mash big ones.
#14
Senior Member
I've got them on a Topanga, a Sorrento and 2 Ascent EXs. Can't really tell any difference between them and regular rings.
#15
missing in action
Join Date: Nov 2007
Posts: 4,483
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Liked 49 Times
in
29 Posts
I've never seen that study, thanks for pointing it out jonainmi! If I could offer one minor criticism to Messrs Malfait et al, it would be the commonly heard refrain in the C&V forum: "do your musculoskeletal modeling from the drive side please!"
#16
perpetually frazzled
Join Date: Sep 2008
Location: Linton, IN
Posts: 2,467
Bikes: 1977 Bridgestone Kabuki Super Speed; 1979 Raleigh Professional; 1983 Raleigh Rapide mixte; 1974 Peugeot UO-8; 1993 Univega Activa Trail; 1972 Raleigh Sports; 1967 Phillips; 1981 Schwinn World Tourist; 1976 Schwinn LeTour mixte; 1964 Western Flyer
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Likes: 0
Liked 6 Times
in
6 Posts
I have a pair of biopace rings on a Nishiki Modulus (stock set). In the 52, you can't really tell that it's not round, but switching from that to a cannondale with a round 52, you can tell a difference in pedaling. The little ring (42? I think) is also biopace, and on that one you can really feel the changes in cadence as you go around the ring - especially at faster RPM (which for me is 110 or so).
I also have a Nishiki touring bike that was pre-biopace. It has a round 52 ring, but the other two rings are elliptical (I want to say they're 36 and 46). Those are just weird - you spin super fast going down in the pedal stroke, but then kinda laze along on the top. It gives the illusion that you're spinning faster than you really are; however, you really do get some nice pulling power with the 36 - more than expected with the gears you're given.
I also have a Nishiki touring bike that was pre-biopace. It has a round 52 ring, but the other two rings are elliptical (I want to say they're 36 and 46). Those are just weird - you spin super fast going down in the pedal stroke, but then kinda laze along on the top. It gives the illusion that you're spinning faster than you really are; however, you really do get some nice pulling power with the 36 - more than expected with the gears you're given.
#17
Member
Thread Starter
Join Date: Aug 2012
Location: Arkansas River Valley
Posts: 28
Bikes: 1984-88? Huffy TechtraLITE
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
From what I can gather, there seems to not be much of a difference between non-round rings, and round rings.
#18
Senior Member
Join Date: Jun 2006
Posts: 20,305
Mentioned: 130 Post(s)
Tagged: 0 Thread(s)
Quoted: 3464 Post(s)
Liked 2,831 Times
in
1,997 Posts
For low cadence, say 60 rpm or less (like slogging up hill, Biopace or Rotor work ) but not so much that I need them. For spinning, no.
#19
Senior Member
Join Date: Aug 2008
Location: NYC
Posts: 191
Bikes: Current: Wabi Classic, '91 Bridgestone Rb-1. Past: '92 Bridgestone RB-1, '02 Lemond Zurich, '91 Trek 520, '85 Schwinn Madison, '80s Panasonic conversion fixie
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
couldn't tell the difference either. FYI, I have a set of biopace chainrings from an old Trek if anyone wants .... can't do anything with 'em. Local to NYC can have 'em free.
#20
Senior Member
Join Date: Aug 2010
Location: Liberty, Missouri
Posts: 3,120
Bikes: 1966 Paramount | 1971 Raleigh International | ca. 1970 Bernard Carre | 1989 Waterford Paramount | 2012 Boulder Brevet | 2019 Specialized Diverge
Mentioned: 23 Post(s)
Tagged: 0 Thread(s)
Quoted: 129 Post(s)
Liked 77 Times
in
40 Posts
I ran BioPace triple for a while and really didn't notice much difference once I got used to pedaling it. The granny was most noticeably different and I didn't care much for the out-of-round cranking on it, but the middle and tall rings were fine.
#21
Senior Member
Join Date: Oct 2007
Location: Vancouver,Washington
Posts: 228
Bikes: 1988 Cannondale SR500,TREK Mendota 2011
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I have Biopace on my 1988 Cannondale, I really can't tell the difference
#22
自転車整備士
Join Date: Apr 2012
Location: Denver, Colorado USA
Posts: 885
Bikes: '86 Moots Mountaineer, '94 Salsa Ala Carte, '94 S-Works FSR, 1983 Trek 600 & 620
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Likes: 0
Liked 3 Times
in
3 Posts
I rode BioPace when they first came out, and felt the benefits right off; I could feel a difference in my knees, and my spin felt smoother.
Almost 30 years later, and after having surgery on BOTH of my knees (both ACL's, right MCL and meniscus) I put a set of them back on my
commuting bike. This time the benefits were more obvious... no joint discomfort at all while spinning, and much less noise from my knee joints!
My cool down is also less painful after a long ride.
I was sold on them back in the 80's, and now I have them on all of my bikes. If they're in good condition I'll take them off anyone's hands!
(74/110 BCD only, 26/36/46 preferred but if you have 28/44/50 I'll take those, too)!
Almost 30 years later, and after having surgery on BOTH of my knees (both ACL's, right MCL and meniscus) I put a set of them back on my
commuting bike. This time the benefits were more obvious... no joint discomfort at all while spinning, and much less noise from my knee joints!
My cool down is also less painful after a long ride.
I was sold on them back in the 80's, and now I have them on all of my bikes. If they're in good condition I'll take them off anyone's hands!
(74/110 BCD only, 26/36/46 preferred but if you have 28/44/50 I'll take those, too)!
Last edited by oldskoolwrench; 08-29-12 at 06:59 PM.
#23
Chainstay Brake Mafia
Join Date: Mar 2011
Location: California
Posts: 6,007
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Likes: 0
Liked 11 Times
in
10 Posts
I rode BioPace when they first came out, and felt the benefits right off; I could feel a difference in my knees, and my spin felt smoother.
Almost 30 years later, and after having surgery on BOTH of my knees (both ACL's, right MCL and meniscus) I put a set of them back on my
commuting bike. This time the benefits were more obvious... no joint discomfort at all while spinning, and much less noise from my knee joints!
My cool down is also less painful after a long ride.
I was sold on them back in the 80's, and now I have them on all of my bikes. If they're in good condition I'll take them off anyone's hands!
(74/110 BCD only, 26/36/46 preferred but if you have 28/44/50 I'll take those, too!
Almost 30 years later, and after having surgery on BOTH of my knees (both ACL's, right MCL and meniscus) I put a set of them back on my
commuting bike. This time the benefits were more obvious... no joint discomfort at all while spinning, and much less noise from my knee joints!
My cool down is also less painful after a long ride.
I was sold on them back in the 80's, and now I have them on all of my bikes. If they're in good condition I'll take them off anyone's hands!
(74/110 BCD only, 26/36/46 preferred but if you have 28/44/50 I'll take those, too!
#24
Senior Member
jonainmi, A very interesting read, thanks!
The article plainly points out the advantages and disadvantages of each design tested. It also allowed me to more fully understand why some cyclists rotated the the Biopace chain rings to the cyclist's positive effect. I was a little surprised at how close a Biopace chain ring compares with a circular chain ring. I can now see why the oval chain rings are becoming popular (again?) in road racing, or primarily time trialing, but I think those designs put alot of load on the joints; a case of give and take I suppose.
Brad
The article plainly points out the advantages and disadvantages of each design tested. It also allowed me to more fully understand why some cyclists rotated the the Biopace chain rings to the cyclist's positive effect. I was a little surprised at how close a Biopace chain ring compares with a circular chain ring. I can now see why the oval chain rings are becoming popular (again?) in road racing, or primarily time trialing, but I think those designs put alot of load on the joints; a case of give and take I suppose.
Brad
#25
Chainstay Brake Mafia
Join Date: Mar 2011
Location: California
Posts: 6,007
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Likes: 0
Liked 11 Times
in
10 Posts
the thing that seems strangest to me is that almost all of the rings saw improvement by rotating them away from the recommended angles from their creators. i would assume the people designing these things would have found the ideal angle in their R&D phase