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Oval crankshaft
I apologize in advance. I realize this group is not for advice about sale
items, but I have technical question about a bike I am thinking of buying and would like some input. Saw a 20 year old Raleigh chrome alloy Super Sport for sale at a yard sale tonight for a $100. The owner recently put in an oval crank. It's a Bio____? (Sorry, don't know the full name.) Seemed kind of an odd set up, but he said it allowed you to put more power into the pedaling. Didn't get to ride the bike as the front tire was low on air. Plan to bring my bike pump tomorrow to test ride it. The bike seems like a pretty good deal as it had a nice feel, new parts, like new wheels, seat post and this crank. I'm going to offer $75. But, I don't know anything about these oval cranks. Are they any good? Do they put more pressure on your knees? Do they feel weird riding? Or, are their any other problems associated with this type of crank? I don't have need for a racing type bike. All I do is go on relatively flat trails about 20-25 miles. I currently have a much older steel bike. It's starting to feel too heavy for my aging body. I've had it for 28 years. It's served me well as I just use it to work out. Thought of getting something lighter. But, I don't like the feel of some of these new light bikes. I'm hoping this bike will suit my needs. |
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#2
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Oval crankshaft
The crank itself is pretty standard, it is the chain rings that are not (I am
not sure about the inner which may be circular). These are Shimano Biopace rings and the intent was to deliver a more constant power output through out the crank's rotation - trying to eliminate top-dead-center, I guess. They were made for at least a few years but have since died away (although something like them has been used recently by a couple pro racers in specific events). At any rate, some folks love them, some hate them. I have no personal experience. But I doubt the feel that much different than standard, circular rings or that they would offer much disadvantage or advantage to you in the type of riding you describe. Of course, if you do not like the oval ring(s), you can easily replace them with circular rings. Charlie S. wrote: I apologize in advance. I realize this group is not for advice about sale items, but I have technical question about a bike I am thinking of buying and would like some input. Saw a 20 year old Raleigh chrome alloy Super Sport for sale at a yard sale tonight for a $100. The owner recently put in an oval crank. It's a Bio____? (Sorry, don't know the full name.) Seemed kind of an odd set up, but he said it allowed you to put more power into the pedaling. Didn't get to ride the bike as the front tire was low on air. Plan to bring my bike pump tomorrow to test ride it. The bike seems like a pretty good deal as it had a nice feel, new parts, like new wheels, seat post and this crank. I'm going to offer $75. But, I don't know anything about these oval cranks. Are they any good? Do they put more pressure on your knees? Do they feel weird riding? Or, are their any other problems associated with this type of crank? I don't have need for a racing type bike. All I do is go on relatively flat trails about 20-25 miles. I currently have a much older steel bike. It's starting to feel too heavy for my aging body. I've had it for 28 years. It's served me well as I just use it to work out. Thought of getting something lighter. But, I don't like the feel of some of these new light bikes. I'm hoping this bike will suit my needs. |
#3
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Oval crankshaft
"David White" wrote: (clip) But, I don't know anything about these oval cranks. Are they any good? ^^^^^^^^^^^^^^^^^ Not really. They were a flop, and gradually became rounder with the model changes, and then disappeared. If you did a blind test, I'll bet you couldn't tell which bike had the Bio-pace. I wouldn't base the decision to buy or not buy the bike on that factor. |
#4
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Oval crankshaft
Interesting to see that Bobby Julich rides a Bio-Pace-like chainring,
though. It's called a Harmonic or O.Symetric. It seems way more ovalized than the Bio-Pace, as I recall them. Wonder what the differences are... -- --------------------------------------------------------------------------------- "Be bold, and mighty forces will come to your aid" -Anthony Hopkins "Leo Lichtman" wrote in message ... "David White" wrote: (clip) But, I don't know anything about these oval cranks. Are they any good? ^^^^^^^^^^^^^^^^^ Not really. They were a flop, and gradually became rounder with the model changes, and then disappeared. If you did a blind test, I'll bet you couldn't tell which bike had the Bio-pace. I wouldn't base the decision to buy or not buy the bike on that factor. |
#5
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Oval crankshaft
"Ed Viladevall" wrote: Interesting to see that Bobby Julich rides a Bio-Pace-like chainring, though. It's called a Harmonic or O.Symetric. It seems way more ovalized than the Bio-Pace, as I recall them. Wonder what the differences are... ^^^^^^^^^^^^^^^^^^ I'm not familiar with O.Symetric, but I do have a set of elliptical chainrings on a Bridgestone mountain bike. At a glance they may resemble Biopace, but there is a world of difference. Biopace are not oval--they are a weird shape that is supposed to make your foot move as though you were walking. The elliptical chainrings are positioned with their long axis at 90 degrees to that of the Biopace, and are designed to give you a longer effective power stroke by getting you through top-dead-center faster. It's not such a big deal on the big ring or the middle ring, but really helps in the "granny" range on hard climbs, when you are pedalling slowly. |
#6
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Oval crankshaft
On Fri, 29 Jul 2005 22:49:47 GMT "Charlie S."
wrote: Saw a 20 year old Raleigh chrome alloy Super Sport for sale at a yard sale tonight for a $100. Could it be a Schwinn Super Sport? Those were made in Chicago from 4130 Chrome Moly Steel tubing. They were quite nice frames, actually hand brazed lugless. The features varied over the years, with the earlier ones generally being nicer than the late ones. The owner recently put in an oval crank. It's a Bio____? (Sorry, don't know the full name.) BioPace? They have a few vocal advocates, but most people don't put much faith in them. Seemed kind of an odd set up, but he said it allowed you to put more power into the pedaling. If they really worked we'd see some racers taking this advantage, but that hasn't happened. Interestingly, this concept has been reintroduced as "new" almost every 20 years over more than a century. - ----------------------------------------------- Jim Adney Madison, WI 53711 USA ----------------------------------------------- |
#7
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Oval crankshaft
On Sat, 30 Jul 2005 00:42:08 +0000, Leo Lichtman wrote:
If you did a blind test, I'll bet you couldn't tell which bike had the Bio-pace. I wouldn't base the decision to buy or not buy the bike on that factor. Me either, though I think they feel very different and could tell the difference blind in two seconds. I'd hate to have to ride a bike with Biopace and be forced to spin at a high cadence, it's really awkward and lumpy. But, they're kinda nice for low cadence stuff, especially off roading or for folks that like to pedal more slowly, perhaps less than 70 rpm. I've got a utility bike with them and they do seem to be nicer to the knees, but I don't ride that bike further than the closest beer/ice cream/dog food store. LOL As mentioned before, if you absolutely hate it, rings are pretty affordable. Buy the bike if it fits. |
#8
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Oval crankshaft
Charlie S. wrote:
I apologize in advance. I realize this group is not for advice about sale items, but I have technical question about a bike I am thinking of buying and would like some input. Saw a 20 year old Raleigh chrome alloy Super Sport for sale at a yard sale tonight for a $100. The owner recently put in an oval crank. It's a Bio____? (Sorry, don't know the full name.) Seemed kind of an odd set up, but he said it allowed you to put more power into the pedaling. Didn't get to ride the bike as the front tire was low on air. Plan to bring my bike pump tomorrow to test ride it. The bike seems like a pretty good deal as it had a nice feel, new parts, like new wheels, seat post and this crank. I'm going to offer $75. But, I don't know anything about these oval cranks. Are they any good? Do they put more pressure on your knees? Do they feel weird riding? Or, are their any other problems associated with this type of crank? I don't have need for a racing type bike. All I do is go on relatively flat trails about 20-25 miles. I currently have a much older steel bike. It's starting to feel too heavy for my aging body. I've had it for 28 years. It's served me well as I just use it to work out. Thought of getting something lighter. But, I don't like the feel of some of these new light bikes. I'm hoping this bike will suit my needs. Sheldon Brown has an excellent article about Biopace: http://sheldonbrown.com/biopace.html and is a regular contributor to this NG. Personally, I have an older hybrid bike with Biopace rings, but I don't really notice a difference from round chainrings. I primarily use this bike for communting, on flat roads at moderate RPMS. I wouldn't worry too much about the rings. Test ride the bike, and if you like it, buy it. |
#9
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Oval crankshaft
"Charlie S." wrote in message news:foyGe.29$2y2.4@trndny02... I apologize in advance. I realize this group is not for advice about sale items, but I have technical question about a bike I am thinking of buying and would like some input. Saw a 20 year old Raleigh chrome alloy Super Sport for sale at a yard sale tonight for a $100. The owner recently put in an oval crank. It's a Bio____? (Sorry, don't know the full name.) Seemed kind of an odd set up, but he said it allowed you to put more power into the pedaling. Didn't get to ride the bike as the front tire was low on air. Plan to bring my bike pump tomorrow to test ride it. The bike seems like a pretty good deal as it had a nice feel, new parts, like new wheels, seat post and this crank. I'm going to offer $75. But, I don't know anything about these oval cranks. Are they any good? Do they put more pressure on your knees? Do they feel weird riding? Or, are their any other problems associated with this type of crank? I don't have need for a racing type bike. All I do is go on relatively flat trails about 20-25 miles. I currently have a much older steel bike. It's starting to feel too heavy for my aging body. I've had it for 28 years. It's served me well as I just use it to work out. Thought of getting something lighter. But, I don't like the feel of some of these new light bikes. I'm hoping this bike will suit my needs. I've seen a Bio-Pace triple crankset fetch $52 on ebay, so they have some value. |
#10
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Oval crankshaft
No news on the bike. I called today and didn't hear back. Will let you
know what happens. I am not clear on the bicycle terminology. From what I understand the crank is the arm that the pedal attaches to. And, includes the chain rings? (what the chain rests on in the front end of the bike). I guess what I really want to know is, if I didn't like this Biopace, would I have to replace the crank (arm) and chain rings? It is all one piece? What is the price for a decent lower end model? The arm or crank looked pristine as though it were well machined. I didn't look real carefully, but the chain rings didn't look as new. (could be wrong here) In response to another poster, he definitely indicated it was a Raleigh.... I may be off if he said it was a super sport. Did a Google search, came up with the Schwinn, not a Raleigh Super Sport. Maybe I didn't hear him right. After reading all the posts and links, I get the feeling the Biopace won't make any difference to my type of riding. (Then again, if I start passing you all on the trail, I'll know I'm on to something:-) "David White" wrote in message ... The crank itself is pretty standard, it is the chain rings that are not (I am not sure about the inner which may be circular). These are Shimano Biopace rings and the intent was to deliver a more constant power output through out the crank's rotation - trying to eliminate top-dead-center, I guess. They were made for at least a few years but have since died away (although something like them has been used recently by a couple pro racers in specific events). At any rate, some folks love them, some hate them. I have no personal experience. But I doubt the feel that much different than standard, circular rings or that they would offer much disadvantage or advantage to you in the type of riding you describe. Of course, if you do not like the oval ring(s), you can easily replace them with circular rings. Charlie S. wrote: I apologize in advance. I realize this group is not for advice about sale items, but I have technical question about a bike I am thinking of buying and would like some input. Saw a 20 year old Raleigh chrome alloy Super Sport for sale at a yard sale tonight for a $100. The owner recently put in an oval crank. It's a Bio____? (Sorry, don't know the full name.) Seemed kind of an odd set up, but he said it allowed you to put more power into the pedaling. Didn't get to ride the bike as the front tire was low on air. Plan to bring my bike pump tomorrow to test ride it. The bike seems like a pretty good deal as it had a nice feel, new parts, like new wheels, seat post and this crank. I'm going to offer $75. But, I don't know anything about these oval cranks. Are they any good? Do they put more pressure on your knees? Do they feel weird riding? Or, are their any other problems associated with this type of crank? I don't have need for a racing type bike. All I do is go on relatively flat trails about 20-25 miles. I currently have a much older steel bike. It's starting to feel too heavy for my aging body. I've had it for 28 years. It's served me well as I just use it to work out. Thought of getting something lighter. But, I don't like the feel of some of these new light bikes. I'm hoping this bike will suit my needs. |
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