stapfam

They seem to be getting the occasional mention right now and I am wondering if anyone has done any real tests to see if they work better than a conventional chain ring?

My only experience of them was on a bike about 15 years ago. It was an old secondhand bike then so no idea how long they had been around. I did not find any advantage to using them at the time and the bike was passed on to someone else. I rode with him and the only comment I could pass is that he used to throw chains a bit more frequently than to did on his previous bike. I put this down to him keeping pressure on the pedals when changing and with a rear derailler that was constantly moving to keep the chain under tension.

So has any one used the "NEW" bio-pace rings and found them of any advantage over a convential ring?

BluesDawg

Are you asking about actual Bio-Pace or the new designs based on similar concepts?

The Weak Link

Bio-Pace sounds like something you catch and then have to take Bicyclovir for.

I'll be here all week. Try the roast beef.

Velo Fellow

I rode original biopace in the late 80's. In retrospect, it was a notion then that was riding the crest of the new "CAD" (computer assisted design...a nifty, trendy term at the time that was being touted on everything from rings to bottle cages). At first, it felt uneven like you're riding a soft tire losing air. Despite its claims to "enhance the power phase of your pedal stroke", I found a more natural spin when I changed out to normal round rings. No experience with the "new" BioPace. More marketing hype?

Sixty Fiver

It was a case of sound design and poor marketing that is being re-visited now, some 20 years later.

They really shine when one is climbing (I use them on my utility bike), can eliminate some bounce when one is spinning those pedals at very high cadences, and are easy on the knees as they unload the drive just a little when the knee is under the most loading stress.

Anyone with a smooth and well developed pedal stroke is not going to appreciate these as much as someone who does not and will notice their rotational difference more.

brotherj

I've ridden Biopace rings on my Trek 700 for about three years. When I first got the bike they felt "funny". Couldn't really place what the feel was, but very quickly didn't notice. Below is a link to Sheldon Brown's article about them

https://www.sheldonbrown.com/biopace.html

BluesDawg

This may mean something to some of the engineer types out there. I didn't try to read it myself.
https://www.noncircularchainring.be/

Bobby Julich was using one type of non circular chainrings in competition and Carlos Sastre used Rotor Q-Rings in winning the 2008 Tour de France. In fact, all of the Cervelo TestTeam riders are using them this year. Thor Hushov was using them when he won stage 6 of the tour Thursday. Who knows? Maybe there is something to it.
https://www.pezcyclingnews.com/?pg=fu...atname=Toolbox

Artkansas 

Well, my Hard Rock with biopace rings definitely climbs better than my recumbent without them, but there are so many other variables that I can't pin it down to the biopace.

BluesDawg

^^^^^

n4zou

A couple of years ago 42/32/22 Bio Pace Rings started selling for high prices on ebay. A professional rider swore by them. Soon others were scouring the country for Bio Pace Rings causing the high ebay prices for them. Someone at Shimano picked up on this and went back into production. I use them myself on my touring bike. They are much easier on the knees. After obtaining a touring bike with Bio Pace I rode it for a couple of hundred miles over a week making sure it was what I wanted before spending more money on it. I thought the frame geometry was improving my knee comfort on long rides. I striped the bike and rebuilt it. This included removing the Bio Pace crank and replacing it with a new crank. Thats when I noticed the bikes frame geometry was not associated with the comfort level on my knees. I put the old Bio Pace crank back on and noted how much easier it was on my knees. Needless to say I am a convert.

Rixtory

had them on my first really nice road bike - 1986 Cilo. I ended up in mid 90's replacing the front crank with Shimano 600 Biopace, but this one doesn't seem as oblong as the old 105 did.

zonatandem

Used them back when (80s) on a triple. Only time it felt 'different', but not necessarily better, for me was when it was on the inner small chainring.
Thought they were just more hype than function.

wobblyoldgeezer

I don't have any views on the question concerning 'new' bio pace rings - but for what it's worth

My second best, and still good, bike is a 1990 Specialized Sirrus Triple - lugged steel, drop bars, down tube indexed Shimano 105, advertised 19 years ago as a 'fast day tourer', which I've used and enjoyed as my main bike until 2 years ago when I bought a newer steel/carbon machine with Ultegra 50/34 compact .

The Specialized has Bio-pace triple crankset. I still like it, and it's my tourer of choice. I'm aware that I like it best as a tourer, and that the cadence it encourages is more 'touring', maybe 75 circles a minute, and I'm happier at a higher (95?) cadence on the round Ultegra/FSA crank and gear set on the new one. Trying to spin that fast on the bio-pace has me bouncing in the saddle.

Never had chain-throwing problems on either. Both good, but the bio-pace suits me better for longer/slower. I remember that back in 1990 the advertised advantage of bio-pace was for runners transitioning to cycling who might have more of a 'striding' than 'spinning' approach.

Love 'em both!

BluesDawg

I have never owned a bike that had Bio-Pace and have only ridden them a little. I noticed no real difference. I have worked on some bikes with Bio-Pace rings and I know that setting up the front derailleur is trickier.

I was not aware that Shimano was producing them again. I have not found them being sold anywhere except old ones on eBay.

Pat

I recall biopace rings from way back. The notion is that your are pedalling fewer teeth in the dead part of your stroke and more on the power stroke.

THere is a problem with biopace rings. The higher your cadence the closer to round you will want. The old biopace rings were nearly round on the big ring, less round on the middle ring and darn near square on the small ring. I had a set and I liked spinning in the small ring on steep hills. It felt like pedalling a square. I ripped off the small ring and put on a round.

They became nearly universal and sold initially at a premium. THen people learned about round rings again and round rings sold at a premium.

They are a good idea that does not really work. They have had at least 2 incarnations in the past and have been weighed in the balance and found wanting.

stapfam

This is my feelings completely- but I am prepared to think that Modern technology- and a lot of testing- MAY have improved the NEW biopace rings over the old form. I am just not prepared to get a set till it is proved conclusively that they do work. and that proof is not there yet.

BluesDawg

I'm still not clear on the question of whether or not there are any new Shimano BioPace rings. I know there are the Q-Rings by Rotor which are kind of similar in concept, but different in design.
Can anyone provide a link to any new Shimano BioPace?

BILLB58

I mounted a set of "Q Rings" on May 7. "Q Rings" were made by an independent company, but Schimano bought them this past winter. They were not cheap, but since I needed to replace my worn large ring on my Dura Ace 7800 wheel, I thought I would try them. I did have to raise the front derailleur a bit. I have about 1200 miles on them at this point. It definitely took a bit to get used to them. I commute 23 mi. R/T every day. At first, I felt I was a bit slower with them in headwind conditions. This was probably more because of my being in a higher gear than I should have been because of the oval effect. I was in the same gear that I normally would have been in at that time. I was ready to take them off and scrap the idea, after the first two weeks.

Then I tried a different approach, and set my computer to cadence, and started to focus on that. After about two weeks of that, I think I got my shifting in tune to the "Q Rings" rather than my old multi-year, same set of gears method. I live in the big ring and just shift the rear. Now I am quite pleased with my decision.

I notice a significant increase in acceleration from stop lights. I can't quantify that, but I "feel" quicker.
In headwind conditions...lately just about every night commuting home, I am not "noticing" any change. In no wind or low wind conditions though, my normal speed on straight-aways is between 21-23 mph. Now I seem to be doing 23-25 mph. I am crediting the "Q Rings" with that 5 to 10% improvement.

This has been my very limited experience.....I don't keep track of a lot of statistics....so unfortunately, the soft, fuzzy "feel" is positive from my perception.

TromboneAl

The biopace rings on my wife's 87 Centurion have never thrown a chain.

The Consumer

Im running a bio pace ring on my fixed gear bike...definatly not the best idea but no chain problems yet. Although I have finally found a round ring to swap it with so might notice the difference once its on but it might just ruin the whole charecter of the 20 quid bike (borderline deathtrap).

Garfield Cat

Brad Wiggins uses the French version from O Symetrics. Try www.osemetric.com. The Cervelo Test Team uses Rotor Q Rings from Spain. Try www.rotorbike.com

The rotorbike.com site does have technical data about its rings.

waldowales

I've been riding a set of original BioPaces rings on my old Hardrock for over a year. If I couldn't see them, I wouldn't know they are not round. I've never thrown a chain, and why anyone would think the derailer is moving more is a mystery to me, as mine doesn't. The chain tension does not change as the rings rotate.

Sixty Fiver

https://go.bikeforums.net/?id=42X1295...2Fbiopace.html

I used to think and Sheldon and I were the only folks who appreciated Biopace rings... they have their place and are not for everyone but the science is sound.

Retro Grouch 

Of course, Shimano did.

Unfortunately, the factor that got left out was cadence. At one time, Shimano was marketing two different bio-pace designs. The Dura Ace design was much "rounder" than the design used in the lower groups. Granny gear chainrings looked almost square but I reckoned it was about 1 gear easier for grinding up a steep hill.

My suspecion is that the faster you pedal the more momentum carries your feet over the "dead centers" and the less benefit you get from biopace chainrings. I've read lots of posts from folks who say they love biopace chainrings. That tells me there's a benefit. If I'm right, the benefit probably only helps the people who ride at low cadences.

Pat

Well, Sixty Fiver, I guess I spoke to emphatically. I run a high cadence. Even with the very mild distortion on the big ring in biopace, it still always felt a little funny. As I said, the small ring drove me crazy. I think it was probably optimized for an rpm of something like 60. But you are probably right. They probably worked very well for certain people.

I think the problem with the whole concept is you need more distortion from round the slower the cadence goes. That makes biopace and other eliptical designs not generally applicable.