So, oval/elliptical chainrings…

Not that I’m buying any, but I understand the ‘principle’ behind them – easier in certain point of the pedal stroke etc.

So when they quote, say for arguments sake, a 50t oval chainring, I’m assuming it actually has 50 physical teeth, but will it feel like a 50t chainring at the easiest point of the pedal stroke, rising to, say, 54t at the ‘power’ point? Or am I getting this all wrong (I suspect the latter, and it won’t be first time….)

I think you are roughly correct – it should feel like a smaller ring through the dead spot, then a bigger one when you put the power down? …Ace-ing it to the finish line etc 😉

tazzy is the (unbiased 😉 ) expert

remembering back to my 50T biopace chainring, yep, felt like riding a slightly smaller chainring most of the time, but when you pedaled harder it seemed like the power was being transferred more effectively.

The effect was quite subtle, and was completely negated if you span over a certain cadence as it’d get a bit jumpy, but if you were smooth and steady there was a difference noted.

I seem to remember biopace being ridiculed at the time…I could never tell the difference between them and normal rings.

People really need to get over the Biopace comparison though, as these are exactly the opposite! Biopace made it harder through the dead spot!

Can’t help on the OPs question – I think it’s the former though – I don’t think folk change their ring size when they go to elliptical rings.

tazzy is the (unbiased ) expert

thank you darling

(in personal experience mode, rather than untried, but they must be crap mode 😀 ) I like them, usual trick for ellipticals on a single speed is got 2 or 3 teeth up on what you are currently using, doesn’t “feel” any harder and gives extra speed on the flat spins. (also makes nasty little steep stalling climbs easier)

for ellipticals on geared applications have a look at the road, TT and cyclo cross forums oh and the Sky teams bikes in this years tour, as that’s outside my experience as I’m a simple singlespeedy buffoon.

I Ran biopace back in the day. It didn’t feel any different to me jumping from one bike to the next. The main argument against it as I remember was that the slight difference added up over long journeys and round rings were better suited for long journeys and tired legs.

Can’t help on the OPs question – I think it’s the former though – I don’t think folk change their ring size when they go to elliptical rings.

Tazzy reckoned most people went up 2t on MTB’s, I guess because the limiting facotr in your edal stroke is getting past the deadspot, which is easier? I guess that means your cadence drops by the same ammount too if you ride on percieved effort, and theres the same percieved effort in a higher gear then cadence must drop (or speed increace, which presumably happens to a lesser extent)?

2T up works on an average SS ratio, dunno why exactly but it does. So I guess on a road ring 3, maybe 4 up, it could be proportional – 50T compact to a 53T oval ‘proper’ big ring size. You can’t really talk about big-ringing on a road bike unless it’s a 53T. I’m speculating tho, I have a lame 50T on my road bike these days and only have an oval on my SS.

Not sure I’d compare with Biopace, which imho was a bit dumb. TBH I never really noticed a difference, other than a puzzled look trying to suss out which way round to affix them to the cranks.

Think mine were 42t/52t rings, which I thought was pretty standard back in ’89, but no idea how that compares to circular equivalent. Still got the rings, but that bike has round rings now.

yeah biopace was elliptical in the ‘other’ way to the latest stuff, and shouldn’t be added to the discussion.

Basiaclly you power delivery is lumpy (weak at the top/bottom, strong in the power phase) so the rings try to make it easier for your legs when they are weak, and optimise when they are strong, by altering the effective ring diameter.

sorry perhaps should have said that I ran biopace 1 turn awayfrom what was supposed to. they ran correct (ish) then.

I would have ran egg rings but I was 16 at the time and my part time supermarket pay didn’t stretch to that.

untried, but they must be crap mode

Your usual go at me?…I’ve never said they were crap, just questioned whether they were any better.

AL- chill your boots chap, it was aimed at the usual tinterweb experts who proclaim that it’s just bio-pace again or who don’t listen to what folks that actually use them say about their personal experience. I couldn’t care less and I’m still not sure where you get the “Taz has a biased opinion” from. I use them, I like them. I’ve recommended them to riding mates, the vast majority of which have also found them to be beneficial to their riding. This doesn’t seem to be enough for you though as we must all be part of some vast conspiracy as it never seems to actually get you to shut the …. up. If you don’t like them, fine, if never have any intention of using them, not a problem, but why pop up on every bloody thread about oval, elliptical or egg rings with the same line each time? 😆

Watch Bradley Wiggins’ chain on his last TT of the TDF, there was definitely some ovalness occurring there. If it’s good enough for him …..?

anyone got the link to the previous discussion about somone possibly manufacturing rings for middleburns??

I had a Shimano OvalTech chain set at one point – is that the same thing?

Watch Bradley Wiggins’ chain on his last TT of the TDF, there was definitely some ovalness occurring there. If it’s good enough for him …..?

Of course Sky do not have to pay for theirs. I am deeply sceptical but if the manufacturers were to give me a load I’d use them too.