View Full Version : Biopace folder
Anyone run a BioPace chain ring on their folder? Can you tell us what it is like and did you need a chain tensioner? Planning to get one myself.
invisiblehand
06-14-08, 01:50 PM
That is an interesting question. I have only seen biospace rings on derailer equipped bikes and there is no reason I can think of that would make a folder special in this regard. If you don't get an answer here, I would try the bicycle mechanics or commuter forum and reference internal hubs instead of folding bikes.
James H Haury
06-14-08, 02:41 PM
I have run a biopace chainring on my Older dahon Folder .I have not needed a chain tensioner.
snafu21
06-14-08, 02:48 PM
Are you looking for a solution to a problem that does not exist?
"Biopace chainrings are often cited as the epitome of a solution looking for a problem among the biking press, though there is little evidence to suggest they were particularly bad, just unnecessary. Problems with using these chainrings with a front derailleur (http://en.wikipedia.org/wiki/Derailleur_gears) may well have been the final nail in the coffin for biopace."
I had a Biopace bike and wondered what I'd spent the money on. Now, I just spend the money on a) reducing weight, b) reducing friction, c) staying fit.
The world has moved on since Biopace.
OldiesONfoldies
06-14-08, 06:24 PM
Just fitted a Biopace chain ring on my tikit. I was looking at improving the climbing ability of my bike and dropped in a 42t. Seems to work well though the chain scrapes the chain guard on the smallest cog, only just.
Apart from it being a much more proficient climber at the expense of spinning out downhill earlier due ot the smaller chain ring, the Biopace does feel a wee bit more"efficient" in my opinion, but not earth shattering. Maybe I'm not a strong rider so need ALL the help I can get.
Wrote abt this in my blog if you are keen: http://lovethefold.blogspot.com/2008/06/climbing-tikit-for-30.html
geo8rge
06-14-08, 07:18 PM
How would the chain ring and the folding mechanism interact? Why would it make any difference. FWIW I have a biopace on a 20" fixed gear folding bike, no tensioner. Tensioning is tricky as the tension changes with chain ring rotation. I believe the late great Sheldon Brown thought it's best use was the smallest ring on a triple. The best thing about it is that it makes me feel unique and superior to all others with circular chain rings.
I had a Biopace on a singlespeed commuter and nrode it for a long time until it wore out. I did not detect any difference whatsoever.
Sheldon Bown put BioPace rings on all of his single speed bikes:
http://sheldonbrown.com/biopace.html
I had a Biopace on a singlespeed commuter and nrode it for a long time until it wore out. I did not detect any difference whatsoever.
What do you mean? did you test it?
Meaning, I could not detect any difference between round and biopace rings wrt pedalling. They all felt the completely the same. If I didn't know there was a biopace ring on, I wouldn't have known it from pedalling.
snafu21
06-15-08, 08:49 AM
I couldn't tell the difference between my Biopace bike and my other when I had both. But I'm no masher of pedals. I sold that bike to my chum who still has it, it's now 15 years old. I phoned him up today - no, he can't tell the difference either...
Perhaps some can, but....... I was quite pleased to find it on my old bike though. It was like those Bulova Accutron watches - revolutionary (haha) at the time, but possibly outdated now. If my next bike had one fitted, I'd leave it on there.
Owner of LBS told me that one wouldn't feel any difference in pedalling with a BioPace ring if under 110 rpm. It would be more like when you go up a hill that you would normally have to take an 1st and suddendly it feels a bit too easy and you find that you are able to take it in 2nd. Like a 15% increase in efficiency. That would help a lot when in the last gear too.
bicyclridr4life
06-16-08, 12:25 AM
one of my mountain bikes has bio-pace chain rings. It felt WEIRD until I got used to it.
Sixty Fiver
06-16-08, 12:33 AM
Biopace rings work fine in any place you would use a round chain ring and do not need a tensioner for single speed applications if you have a bike with horizontal dropouts.
Sheldon and I were both fans of Biopace and I have used them on ss and fixed gear bikes for years... tensioning them is actually fairly simple as with a Biopace you know where the chain is not round and their shape is precise so you can make fine adjustments from that point.
OldiesONfoldies
06-16-08, 07:18 AM
While not an expert like many of the techies here, I feel the Biopace on my tikit improves hills climb performance. By virtue of its shape, you can actually feel that the ring is NOT round when you climb - and its weird shape actually seems to help transfer the power and improve the "rhythm" of the pedalling cycle.
Hope I'm making sense? My Speed Pro too has the Vista Sycnro chain ring which is similiar to the Biopace. The top Dahon riders of my club seem to agree that it helps esp in the climbs too.
http://www.vistadeal.com/En/Produits_Plateau_Synchro.php
Guess at the end of the day, it boils down to whether you agree with Sheldon Brown's analysis and I for one hold his views in the highest regard.
http://i98.photobucket.com/albums/l260/oldiesonfoldies/SpeedPro.jpg
Beemster
06-16-08, 08:43 PM
My first mountainbike which came out in the late 80's had Biopace rings. I beat the heck out of them and recently dumped some on Ebay as "Ancient Caveman Chainrings". Grease, bent and worn teeth and they fetched more money than they cost new. I still have more hanging on the wall avoiding the scrapyard and waiting for the next collector to venture along.
They were all the rage then, but there was a reason that they went away.
I had a biopace crankset in the late 80's (when they were all the rage ;) ). I never had the feeling that it was doing much to help, and at times I found the pulsing feeling annoying. I replaced those rings with "Round Tech" (I kid you not, it says that on the package.) chainrings that were an "innovation" in the early 90's.
Speedo
About a month ago I put a biopace ring on my Downtube Mini because, after all, what would Sheldon do? Objectively, at this point, I have noticed little or no difference like this.
On the other hand, however.... Last week I set a new speed record for that bike, which was 31.8 mph. At least, I think that's what it was; for obvious reasons I didn't want to spend too much time looking at the mileage computer! This was coming down the east side of the Queensborough bridge; previous top speed on that bike, also on that stretch of road, had been 28 while drafting a roadie and 26 unassisted. I presume my new short crank arms and more aerodynamic position due to flipped handlebar both helped somewhat; I can only speculate what other factors --tail wind, what I had for lunch, etc-- may have played a part. At any rate, to hit that speed I must have been pedaling somewhat over 120 rpm, and this does seem to be easier on the biopace ring than otherwise.
I can recommend the similar Q-Ring product from Rotor
I have the 54T Aero on my Dahon Helios.
http://www.rotorcranksusa.com/
This is a good technical page that is easy to miss:
http://www.rotorcranksusa.com/i1-q-rings.shtml
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