oval chain rings

t0pc4t

my bro loves to ride but his knees are totally shot, the cartilege in them is totally done and dusted. So riding is very painful for him.

I read an article about Fabien Barel and it said he ran oval chain rings as he'd had a knee injury. Does anyone know if they're easier on the knees? Anyone got any experience of using them?

Chunkers1980

Only years ago - was named biopace. Died.

I'd say the Road guys would have more of a veiw on this

t0pc4t

thanks

nicklouse

are you talking about oval rings or Oval rings?

there is a brand called Oval.

there are also many brands producing oval rings.

the Shimano Biopace were one.

then there is:

EGG

Rotor Q rings....... and more.

njee20

Biopace were 'wrong' by 90 degrees, they accentuated the dead spot. Rotor Q-Rings and Osymettric rings (which I don't think are available for MTBs) are the right way round.

A few friends use Q-rings, and all like them. They're not cheap, I'd try and get hold of a set to try first, I'm not sure quite how much difference they'd really make if his problems are that serious.

t0pc4t

it's the Biopace type oval shaped ones I mean (I think, just saw a reference to them in that Fabien Barel article)

cooldad

I have Biopace on a road bike and an old hack/MTB.
I also have old knees, and one is a bit wrecked from an old rugby injury.
Can't say I notice any difference between those and the round ones on my newer bikes.
It does feel a bit funny/different on the road bike for the first few minutes though.

t0pc4t

thanks CD

better responses than the roadies, first reply I got there was 'get knee replacements' bellends.

I cannot believe I used to be a roadie through and through, thank heavens I saw the light. I do still ride on the road still but without the attitude.

cooldad

t0pc4t wrote:

thanks CD

better responses than the roadies, first reply I got there was 'get knee replacements' bellends.

Sheepsteeth on the road forums?

njee20

Like I say, Biopace were wrong, and the current crop actually work, how much by is harder to quantify!

cat_with_no_tail

njee20 - Just rotate the cranks by 90 deg then, that'll solve it.

Chunkers1980

What if they were 5 bolt

Pokerface

t0pc4t wrote:

thanks CD

better responses than the roadies, first reply I got there was 'get knee replacements' bellends.

I cannot believe I used to be a roadie through and through, thank heavens I saw the light. I do still ride on the road still but without the attitude.

Being a Roadie (and Trackie), I'm not sure I should respond given your predisposition to dislike 'us'!!

However, discriminating based on the type of bike you ride is stupid, so here goes.

I use the Rotor Q-Rings on my road, TT and even track bike. I swear by them. This is the important part: for ME, they smooth out my pedal stoke, add power, make climbing easier and are definitely easier for the knees. They were easy to get used to and I even switch between bikes with round rings with no negative effects.

They may not work for YOU, but everyone I know that has tried them has liked them.

t0pc4t

as I said, I'm also a road rider, I merely found it a bit disconcerting that the first response I got was 'get replacement knees'. Having seen the situation up close I'm not inclined to be flippant.

Thanks for your response, sounds like oval rings might at least be worth a demo and, in fairness, the second post pointed me towards a shop where you can try out oval rings.

Might even give them a go myself.

cooldad

njee20 wrote:

Like I say, Biopace were wrong, and the current crop actually work, how much by is harder to quantify!

I've read that as well. My point was that they don't seem to make any difference to my knees one way or the other.
I'm sure the new ones are better, but for MTB with lots of movement and position change, and a few bumps, not sure if they would make as much difference as they would on a road bike where pedallin action is much smoother.

Anonymous

If your knees are as shot as you say they are, but I'm sorry, maybe you need to find a sport which is gentler on the knees.
Swimming maybe?
(And no, I'm not being sarcastic - I mashed up my knees wuite bad, I have a feeling of how much abuse they put up with on an MTB)

Or, maybe not quite as drastically, GO AND SEE a proper physio. Definitely sounds like you need some professional advice.

t0pc4t

it's my brother not myself McGee and yeah he is under the care of a consultant and a physio

he won't ride off road anymore due to the effect on his knees so sticks to road stuff, the question was more a general one about oval chain rings as opposed to specifically for off road stuff. I didn't make that very clear.

Anonymous

Fair enough. I genuinely didn't mean it out of spite, just concern about how bad his knees are.

I'm not sure how the oval chainrings could help. What they actually do is decrese the effective gearing over the top and bottom of the pedal stroke, and increase it on the vertical parts of the stroke (well, as near as dammit, for a simple explanation).
so, all things considered, I don't see how they'd alleviate any knee problems.

Chinley Churner

I love my Q-rings on my mtb... you notice then most when you're on a techy climb and suddenly need a spurt of power/acceleration to get you over an obstacle.. it just seems to be there easier with the Q's.... I test ride quite a lot of bikes with regular rings and the Q's just seem to give me a smoother and more even pedal stroke.

bikaholic

Buy some ordinary round rings, then etch the followin into them: "Ergonomically designed to be knee friendly and scientifically proven to augment power transfer".

The placebo will work wonders and your bro will come to swear by them, OP. He'll focus more on riding and not concentrate on his knees.

Put up a webpage to extol the virtues of these "ergonomically modified" rings, and subtley include with it good practice (knee friendly) pedalling techniques and strengthening excercises - that will elevate the wonder of the rings and enforce the placebo.

Arkady001

As an ex-roadie myself I can see that there might be some benefit on a road bike if your pedalling style was smooth enough, but on a Mountain-Bike, so many other variables are in play that I think you'd be deluding yourself if you thought the shape of the rings would make a significant difference.
Proper seat and crank-length set-up would be far more beneficial, i'd have thought.

captainfly

Both my knees are wrecked with arthritis and so are my ankles (immune system attacked cartilage) and have found that shorter cranks make the biggest difference as it reduces knee flex and it is the flex on the power stroke that causes the most pain. Combine it with lower gearing and it should be feel better.

ddraver

Does he ride a full suss? He could tell us if they reduce pedal bob too??

t0pc4t

no this is on a rigid commuter, he rarely rides off road these days due to the pain thing

I asked here as this is the forum I spend most time in