Found: Prototype Absolute Black Ovalized Wide Narrow Chainrings

absolute-black-narrow-wide-ovalized-chainring-prototype

Absolute Black has been pretty busy, releasing single speed cogs and direct-mount Cannondale Hollowgram narrow/wide chainrings in the past few weeks. Now, joining his 104BCD offerings is an ovalized chainring option.

The part shown here is prototype #3 and not nearly the finished version. AB’s founder Marcin told us it’s proving difficult to get perfect ovalization, so he’s taking his time on this one. Fortunately, he’s able to tell us where it’s headed. The ovalization will be about 1.10, which is similar to what Rotor does. That equates to a 32-tooth chainring with the equivalent of 30-tooth and 34-tooth sections at the extremes.

Marcin says that gives people the common 32-tooth size with the additional speed available from a 34. The other trick is clocking the highest point into the optimum position, so that you’re in the peak of your power band when you’re pushing the 34 equivalent. That lines up the 30 equivalent in your dead band, so there’s less effort required where you’re typically weakest.

The ring has 2mm spacers with threads built into it, so it’ll bolt directly onto a 104BCD without the need for nuts. The spacers help it clear the crank spider arms where it dips down to 30T heights. He says it also improves chainline.

Target release date is late summer (about 4-6 weeks if things go as planned), and only a 32T will be offered. A direct mount version could follow if there’s enough interest.

AbsoluteBlack.cc

 

Comments

chris noble - 06/27/14 - 1:38pm

Awesome, need some cheaper competition for rotor, and the AB stuff is great quality. yes please to direct mount version

Jdog - 06/27/14 - 1:43pm

This is great news as rotor is a asleep at the wheel on this one. I have been hounding rotor to make a 104bcd. N/W ring for months. I finally broke down and bought an adapter spidering sram crank so I could use their odd, proprietary bcd ring. I have a rotor ring on every bike and I can’t say enough how I prefer it to round rings.

This is one of those things that people will scoff at before they have tried it. Laugh if you will, but understand it before you discount the advantage.

Ripnshread - 06/27/14 - 1:51pm

Shimano Bio-pace mid 90′s tech.

Jeremiah - 06/27/14 - 2:01pm

I hope they make a 650b specific version.

Chader - 06/27/14 - 2:12pm

@Jdog,

What do you like about the rings? I’m on round, but find the return to oval rings interesting.

The Conductor - 06/27/14 - 2:35pm

I still have old bio-pace rings in my basement someplace…as I recall, the world gave Shimano a ton of crap over those…so what goes “a-roundish” comes a-round…

Andrew - 06/27/14 - 2:39pm

@Ripnshread Mid 90′s tech marketed badly into oblivion.

craigsj - 06/27/14 - 2:40pm

“This is one of those things that people will scoff at before they have tried it. Laugh if you will, but understand it before you discount the advantage.”

And once you understand it you will discount it. Those who believe in it don’t understand it.

Regardless of the voodoo effectiveness, an oval chainring without the ability to tune the timing is limited. Good thing it’s only 10%.

Rotor has nothing to worry about here.

Roy - 06/27/14 - 3:19pm

Bio Pace and Rotor achieve max chain pull at very different points in the revolution. I have Rotor on every bike and have switched back and forth to round to check myself, and to me Rotor are worth the money over round, and they also have the ability to ‘tune’ with 5 choices of clocking.
The ONLY way I would consider this AB ring will be if they are direct mount SRAM then one can use the splines to clock the ring +/- to tune to my favored feel of when the ring is pulling max chain.

Rico - 06/27/14 - 3:25pm

You guys need to do your homeworks. Bio-Pace stunk because they had the whole thing bass ackwards. Their ovalization was 90 degrees off from Rotor etc. Their system minimized tooth count in the power zone and maximized tooth count in the pedalists dead zone. No comparison between Bio-Pace and Rotor or similar and no wonder they stunk.

Don’t knock it ’til you’ve tried it. I have them on a road bike and do not intend to ever go back to round chainrings.

Spevas - 06/27/14 - 3:27pm

@Ripnshread, The Conductor: It’s the exact opposite of Biopace. OK, 90 degrees different.
@craigsg: Why is there a need to tune the timing of something that’s voodoo?
@ Chader: I ride Osymetric rings, and don’t notice that I ride faster, but the intensity of the burn during hard climbs and sprints is significantly less. Legs feel a little fresher after a long ride.

Tim A - 06/27/14 - 3:40pm

I haven’t spent much time on them with gears, but Rotor’s chainrings feel pretty great on a singlespeed (the change in length is negligible). The slight leverage boost where you can use it really does work well for me.

ahram - 06/27/14 - 4:35pm

This is going to be a wonderful match to clutch system derailleurs..

Hotep - 06/27/14 - 4:41pm

I have no sincere opinion, so I’m going to post something snarky about this product or similar products, or hell even products that have absolutely nothing to do with it.

Joop - 06/27/14 - 4:45pm

It`s sits all between the ears :-)

Bah Humbug !

Colin - 06/27/14 - 4:46pm

I know I am mostly sarcastic , but in all seriousness, wont you be fighting the clutch in a Shadow+ or Type2 der. with one of these?

Andrew - 06/27/14 - 5:16pm

Think of it this way. By using oval chainrings you can effectively change how torque is delivered to the rear wheel. Whether oval or round rings are used the rider’s average power output should remain almost exactly the same (hence why most people think they don’t work until they try them). Rotor rings DO NOT work by increasing maximum power output they work by reducing the spike in torque that happens twice per full rotation of the crank (when the crank is at 3 o’clock, or parallel to the ground). Removing the torque spike reduces the small acceleration/deceleration of the wheels, bike, and rider that occurs through every crank rotation. Remember: it uses less energy keeping a motor running at a constant speed than starting and stopping it.

Brendan - 06/27/14 - 5:27pm

Seems like you will be fighting your RD brake every half turn.

Calvin - 06/27/14 - 6:30pm

I can’t wait to buy this! I was planning on getting their 32t ring soon because my race face n/w is worn out. now that it’s oval, it can’t come soon enough. Marcin, even though i’m anxiously waiting for this to come out, take your time with RND and it will turn out great. I can’t wait!

Andrew - 06/27/14 - 7:26pm

Ordered an Absolute black XX1 style chainring on their website, which was easy and reasonably priced. Considering they are based in the UK, shipping here to Canada was ludicrously fast. The photos don’t do the product justice, the machining is really something. This Marcin dude has really brought some game, I hope he sees Absolute Black succeed.

jls - 06/27/14 - 10:42pm

BioPace was actually from the 80′s

Tyler Benedict - 06/27/14 - 11:27pm

Colin – I haven’t tried them so can’t speak from experience, but I don’t believe it would pull in any cyclical manner on the rear derailleur since ovalized rings are able to be used on single speed bikes (which looks really weird, BTW), but the overall chain length between the two stays the same regardless of chainring position.

Vincent - 06/28/14 - 4:16am

would like this in 26T, narrow wide, sram direct mount

craigsj - 06/28/14 - 8:28am

“Why is there a need to tune the timing of something that’s voodoo?”

There isn’t, but if it WAS worthwhile there would be a need. This ring is both fatally flawed in execution and of no value to begin with. A two-fer from a company that doesn’t know what it’s doing.

“Rotor rings DO NOT work by increasing maximum power output they work by reducing the spike in torque that happens twice per full rotation of the crank (when the crank is at 3 o’clock, or parallel to the ground). Removing the torque spike reduces the small acceleration/deceleration of the wheels, bike, and rider that occurs through every crank rotation. Remember: it uses less energy keeping a motor running at a constant speed than starting and stopping it.”

Not that Rotor rings “work” at all, but this is wrong and contrary to Rotor’s explanation.

There is no “motor” here, there are legs. The bike/rider has loads of mass which smooths out accelerations, what matters is the acceleration on the legs. That changes MORE with elliptical rings, not less.

Two things that result from a rotor ring are (1) the need for the leg to accelerate fastest at the point where it is weakest, and (2) the increase in duty cycle on the muscles. The first lowers the maximum cadence and the second limits the ability of the muscles to sustain power.

Despite plenty of time and effort, there has been little success in demonstrating advantages to rotor rings. They are a placebo. Yeah, I’ve used them…a lot.

One thing I always thought they were good for is rocky technical situations where getting through the dead spot is a benefit. Problem is that 10% just isn’t very much. I had 20% and 30% rings custom made but they pedaled so terribly I couldn’t stand having them on the bike. The 20% I could use at lower cadences, the 30% was a total waste of time.

Jon - 06/28/14 - 5:04pm

“The first lowers the maximum cadence and the second limits the ability of the muscles to sustain power.”

The singularly best thing about the Goldtec Wonkey ring on my singlespeed is that it’s far more comfortable to spin at a higher cadence. No more feeling of my legs chopping through the mid-stroke as they accelerate through it.

Better thrutch at low cadence on climbs is more of a handy side benefit, but again it’s more comfortable. If that’s the case then I’m not sure that an increase in leg acceleration makes any difference to power sustainability on a singlespeed at low revs.

I’m sure that the timing of the ring and ellipticity is extremely relevant in how it performs and feels. It should be marked on the rings so that people can argue the toss over it with more ready information :)

absoluteblack - 06/29/14 - 9:10am

Hi All,
Marcin here,

Thanks for all the comments. I will just try to briefly cover few things.

Oval rings actually do have ability to generate more power. That is a fact.
If anyone is interested deeply enough there is a few good scientific articles like that here (39 pages)
http://www.noncircularchainring.be/pdf/Biomechanical%20study%20chainrings%20-%20release%202.pdf

In short words what it means? Good oval rings do have ability to increase peak power by 3-7%.
Is that important for average mtb rider? Rather not, as such rings also require ovality over 1.25. (25%). That is a lot and many people do not feel comfortable riding it.

This is why smaller ovality like around 10% plays a big role in mtb. It will not increase your power but it will smoothen your ride and this is whole purpose. Such small ovality is small enough to not to feel differences in the leg speed pedaling the oval ring, but oval is big enough to make a small difference in the peak zone and dead zone.

What it means for average rider? If you have 30T currently on your bike, you can have now 32T oval ring and still feel it like 30T in your dead zone (cranks vertical to the ground). But when crank are in your peak zone (crank slightly below horizontal level) you will push 34T ring. Sounds a lot but this is just for fraction of a second when you pushing that gear in one rotation. So it does not feel like having 34T all the time at all.

Such ring will make you quicker as you can swap your 30T to oval 32T.

It is also proven that it is a bit safer for knees (vs circular) speaking in very simple terms, if the ovality and orientation of the ring is optimal.

Psi Squared - 06/29/14 - 6:26pm

@absoluteblack: note the paper you cited is only a simulation based on geometry, including geometric assumptions about legs and feet. It does not include any physiological or biomechanical information, such as what the response might be to changes angular velocity throughout 1 cycle on an ovalized chain ring vs. a circular chain ring.

Tom - 06/30/14 - 5:15am

Marcin, can we have some narrow-wide rings in 48t and 50T for single ring road applications please?:)

Danne - 06/30/14 - 6:41am

Waiting for the ovalized 36T BCD120 (XX).

absoluteblack - 06/30/14 - 11:25am

@ Psi Squared – this is just one single article which shows the gains and explains many things from mathematical point of view. There are plenty of them made by Universities in recent years about same topic from biomechanical point of view, but you usually have to pay for them to read. I can only show what’s free.

@Tom – yes we may do it soon.

@Danne – not possible to do 36T oval for 120BCD. It’s better to change a crank which uses 104bcd as you have a lot more options.

Pete - 07/03/14 - 11:00pm

Would love to see oval rings made for gates centertrack! I’ve been using rotors on my single speed for 5 years and love them. Going to the belt, I really miss the oval rings. Psyched they are moving into this space to give us more options!

Jimbo - 07/05/14 - 4:17am

craigsj, agreed that adjustable ring position is pretty vital but far less so on my SS as I’m not seated when climbing hard. I use round and ovals and find that I climb more efficiently on the oval when stood up. When seated the 10% or so makes little odds as I’m spinning. They work for my gear-pusher natural pedaling style and the greater effective gear at the 4-5pm crank position matches the point when my legs have ‘got going’ so I like having that little extra there to push against without having a harder dead-spot gear that stalls me on low rpm climbs.
Placebo or not, they make my bike a little bit more ergonomically suited to me.

Alex - 07/10/14 - 3:55pm

spyderless oval ring will be GA soon here:

http://en.garbaruk.com/news

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