bicyclridr4life
02-01-12, 08:15 PM
Do 48/38/28 Bio-Pace chain rings have the same effective diameter as 48/38/28 round rings?
Thanks
Thanks
Bicycle Mechanics - Bio-Pace Question
Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.View Full Version : Bio-Pace Question
Bianchigirll
02-01-12, 08:20 PM
Yes they do
bicyclridr4life
02-01-12, 08:28 PM
Thank you, I thought they did but was not sure.
fietsbob
02-01-12, 08:28 PM
circumference is the same, but the radius is varied.. D is 2xR..
in different parts of the rotation, that is their whole idea.
so on average it is the same..
in different parts of the rotation, that is their whole idea.
so on average it is the same..
peterw_diy
02-01-12, 09:10 PM
circumference is the same, but the radius is varied.. D is 2xR..
in different parts of the rotation, that is their whole idea.
so on average it is the same..
...meaning you need to check the FD clearance at the spots where R is greatest, and you can (should?) likely lower your FD if switching from oval to round rings. Nobody goes the other way, right?
in different parts of the rotation, that is their whole idea.
so on average it is the same..
...meaning you need to check the FD clearance at the spots where R is greatest, and you can (should?) likely lower your FD if switching from oval to round rings. Nobody goes the other way, right?
bicyclridr4life
02-01-12, 09:48 PM
...meaning you need to check the FD clearance at the spots where R is greatest, and you can (should?) likely lower your FD if switching from oval to round rings. Nobody goes the other way, right?
Actually ... I installed the Bio-Pace crank I took off another bike (only because I could not get the ring sizes I wanted) and put the Bio-Pace on another bike that had a cheap HEAVY as HECK non-replaceable ring Shimano crank, have to raise the FD about 3/16 inch it looks like.
I actually like the Bio-Pace :)
Actually ... I installed the Bio-Pace crank I took off another bike (only because I could not get the ring sizes I wanted) and put the Bio-Pace on another bike that had a cheap HEAVY as HECK non-replaceable ring Shimano crank, have to raise the FD about 3/16 inch it looks like.
I actually like the Bio-Pace :)
DirtRoadRunner
02-02-12, 06:20 AM
Actually ... I installed the Bio-Pace crank I took off another bike (only because I could not get the ring sizes I wanted) and put the Bio-Pace on another bike that had a cheap HEAVY as HECK non-replaceable ring Shimano crank, have to raise the FD about 3/16 inch it looks like.
I actually like the Bio-Pace :)
I had a 1987 Centurion Ironman with a 105 biopace crankset. I liked it too. Though, the first time I went to fine-tune the FD, I had a "WTF!" moment when I realized the chainrings weren't round! I had never heard of such a thing and thought I had bought a junk bike. Can't say I noticed any vast improvement in pedaling efficiency, but at the very least they are a nice conversational piece.
I actually like the Bio-Pace :)
I had a 1987 Centurion Ironman with a 105 biopace crankset. I liked it too. Though, the first time I went to fine-tune the FD, I had a "WTF!" moment when I realized the chainrings weren't round! I had never heard of such a thing and thought I had bought a junk bike. Can't say I noticed any vast improvement in pedaling efficiency, but at the very least they are a nice conversational piece.
ThermionicScott
02-02-12, 08:19 AM
Similar deal for me. When my brother gave me an 80's MTB (it was a size too small for him) that had good-condition BioPace rings, I couldn't resist the urge to transplant them onto my main bike. I can't perceive an improvement in efficiency or knee strain, but I like them anyway. :)
bicyclridr4life
02-02-12, 02:13 PM
... but at the very least they are a nice conversational piece.
Especially when the ... shall we say ... "uninformed" call out "HEY! MISTER!! YOUR CRANK RINGS AREN'T ROUND! I'VE NEVER SEEN A CRANK BENT SO BAD!!! " :o
Especially when the ... shall we say ... "uninformed" call out "HEY! MISTER!! YOUR CRANK RINGS AREN'T ROUND! I'VE NEVER SEEN A CRANK BENT SO BAD!!! " :o
FastJake
02-02-12, 05:05 PM
you can (should?) likely lower your FD if switching from oval to round rings. Nobody goes the other way, right?
Only the enlightened ones :thumb:
Yes, as fietsbob says the average radius is the same but of course it's not the same everywhere.
Only the enlightened ones :thumb:
Yes, as fietsbob says the average radius is the same but of course it's not the same everywhere.
garage sale GT
02-02-12, 05:14 PM
Do 48/38/28 Bio-Pace chain rings have the same effective diameter as 48/38/28 round rings?
ThanksI don't think they do. They are lower when the cranks are horizontal but higher when the cranks are vertical. The pedaling effort is lower except if you use clips or clipless pedals to keep pushing on the cranks when they are vertical, when it is higher.
ThanksI don't think they do. They are lower when the cranks are horizontal but higher when the cranks are vertical. The pedaling effort is lower except if you use clips or clipless pedals to keep pushing on the cranks when they are vertical, when it is higher.
Monster Pete
02-03-12, 03:02 AM
That's true, but a 48t ring will still pull through 24" of chain in one rotation, whether it's round, oval or square. You get a slightly higher gear at some points and a lower gear at others, but the average gear ratio is the same as a round one.