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Climb anything with new AbsoluteBlack 46/30 and 48/32 sub-compact chainrings

absoluteblack micro compact road chainrings with 46-30 and 48-32 gearing combinations
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Compact gearing has seen smaller combinations in recent years due to the popularity of gravel and adventure riding, and the new AbsoluteBlack micro-compact oval chainrings take it to a new low. We’ve seen 48/32 combinations from Praxis, plus Rotor and FSA (who also have a 30/46), but all of those systems require proprietary spiders, cranks and/or direct mount designs. AbsoluteBlack’s version works on standard Shimano 110/4 cranks, and they’re oval.

absoluteblack micro compact road chainrings with 46-30 and 48-32 gearing combinations

AB’s founder says he’s been able to climb a 37% grade on gravel using these with an 11-30 cassette, yet not lose the top end speed needed for regular group rides. His example is that a 53/13T @90rpm gives 46.5km/h(29mph), which is actually slower by 3km/h(2mph) than 48/11T at the same cadence. Yes, you’d be faster in 53/11, but how many of us ever really use that combo? And many more of us wish we had something lower when we’re climbing?

absoluteblack micro compact road chainrings with 46-30 and 48-32 gearing combinations absoluteblack micro compact road chainrings with 46-30 and 48-32 gearing combinations

The challenge to making sub-compact chainrings work on standard Shimano cranksets is that the bolt hole for 32 and 30 tooth chainrings would interfere with the teeth. AbsoluteBlack’s solution is a patent-pending “offset chainring” solution that shifts both chainrings inboard by 2.5mm closer to the frame…similar to what they did for their 30-tooth 104BCD mountain bike chainring. They admit this does affect the chainline, but actually improves it when you’re in the top 2/3 of the cassette, which is where you’ll be for climbing and the whole point of this gearing combo.

The 30-tooth uses a smaller M5 bolt on the narrower part of the oval, which lets it clear the chain above. The taller part of the oval, where you’re applying more torque, uses a larger M7 bolt. The 32-tooth ring uses four M7 bolts. All are titanium, and all thread from the front, through the big chainring, into the small one, so you can install them without removing the cranks from the bike. Other than readjusting your front derailleur inboard, too, no other modifications to your drivetrain are required.

absoluteblack micro compact road chainrings with 46-30 and 48-32 gearing combinations

As for shifting, they say many road bike frames were not designed with a 46-tooth chainring in mind, so you may end up with up to 5mm of gap between the top of the teeth and the derailleur cage. Normally, you’d want about 1.5mm, but AB designed the tooth profiles and shifting ramps to work with the increased gap.

The 48/32 and 46/30 combos were designed specifically to work in those pairs, so they don’t recommend mixing and matching. The precise tolerances required to make it all work smoothly also means they recommend using only a Dura-Ace CN-9000 or SRAM Eagle chain, both of which they’ve tested to work on on modern 11-speed drivetrains.

Prices for the 46T/48T are €105/95£/124$ and for the 30T/32T  76€/67£/87.5$. Small chainrings include necessary bolts in the price. The 46/30 are in stock and shipping now, the 48/32 should be ready by February 1.

AbsoluteBlack.cc

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48 Comments
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David
David
6 years ago

Watching and waiting for a hands on review. Love the oval on two of my bikes (road and mtn) but this would open up 2x gravel with out having to replace the crank. I’m interested!

Reporter
Reporter
6 years ago

Does anyone know an alternative 46/30 that fits in Sram Force BB30 cranks?

Bjoern
Bjoern
6 years ago
Reply to  Reporter

Doval Micro GT might work. Have some on order to try out.

Toine
Toine
6 years ago

why is everyone trying to use a road bike to do mountainbike-stuff? The guy looks ridiculous riding through the snow without a helmet on a road bike.

Chris L
Chris L
6 years ago
Reply to  Toine

Because for a lot of fire road and gravel road riding a mountain bike is ridiculous overkill and often much slower. Keep in mind for several decades most of the Tour de France (including almost all the big climbs) was ridden on unpaved roads. People were riding mountain bike stuff long before the mountain bike was invented.

Don McKee
Don McKee
6 years ago
Reply to  Toine

In the area we live in gravel races are stitched together with secttions of gravel linkled by paved roads. reasonable competitiveness in an overall event requires a bike that is capable both in gravel and on paved tarmack. An MTB is overkill on the gravel roads and terribly slow compared to a road bike on pavement.

EATRIDEGROW
6 years ago

Seriously why no helmet? Even from a PR/marketing perspective, that’s pretty stupid…

Loki
Loki
6 years ago
Reply to  EATRIDEGROW

+1

What, he was going to overheat ? The new chain rings are so good they keep you upright amidst ice and rocks? If it’s a retro-grouch that would fly in the face of the latest tech rings . .. pretty stupid on so many levels.

Technician
Technician
6 years ago
Reply to  EATRIDEGROW

Pretty stupid is to think you know better than that guy from the vid. Everyone should think for himself.

I bet you won’t care if he crashes and gets serious injury. But still you are here to say your “nay” word on the topic. None so hypocritical than someone who tries to show his care when he doesn’t give a flying f*ck.

Robin
Robin
6 years ago
Reply to  Technician

Your assumption that someone doesn’t give a “flying f*ck” is without merit. You have no facts on which to base such a flawed assumption.

Loki
Loki
6 years ago
Reply to  Technician

What?

I could be a brain surgeon, a helmet designer, a marketing exec, any of a number of experts that would know better than some guy in a video!

That is such a short sighted, stupid comment that I am a little baffled at where to start.

For arguments sake lets start with your ridiculous assumption that I don’t care about the hero in question; however, (deleted), I might care about all the people who would then look-see this advertisement, and even if I’m making the vague assumption of their subliminal doom, I care enough about joe public to register my opinion publicly that as a company operating in this industry and promoting themselves as a tech leader that there is no excuse to promote ‘no helmets’ (even if it’s accidentally, no pun intended). See, guy in vid = aspirational symbol. If enough people comment perhaps the next time or the next company will pay attention to the details. If they truly believe in no helmets, then make the statement, own it. And yes sunshine, it’s my opinion that cyclists should wear a helmet, and I’m positing it as that; if you have a differing opinion, it’s your right to express it. Attacking me based on your assumption of my assumption is, well, thoughtless. To often people confuse rearranging their prejudices for thinking (insert snide comment about not being able to think that well with a head injury here).

So, I agree ‘ everyone should think for themselves’, the operative word being think. Your issue here is that you reacted to my nay as a blind knee jerk mother grundy-ism with a touch of the ‘if I criticize something it shows I’m superior’ neediness. Sorry, wrong. I think that in this era the video sends a sloppy and irresponsible message.

John Gallavin
John Gallavin
6 years ago
Reply to  Loki

I think perhaps the Tech guy has fallen off his bike at some time with out a helmet and this is the result. He has a confused brain.!!!

JEREMY MOORE
JEREMY MOORE
1 year ago
Reply to  Technician

He must have nothing to lose up there. Also, he’s certainly insecure which is why he’s no helmetting and wearing baggies

Braulio
Braulio
4 years ago
Reply to  EATRIDEGROW

Stop imposing your helmet fetish upon others. If you want to wear one then go ahead, but stop bitching about those who don’t.

ed
ed
6 years ago

I would actually buy this if their ovals were timed differently. Pity they cant do a 32/50 or 30/50. The loss of speed from 53 to 50 is considerable, to go lower than that is too short. With a 46 you spin out at 30-32mph.

Smale Rider
Smale Rider
6 years ago
Reply to  ed

People don’t actually pedal at 30mph-ish. At those speeds people are coasting down. Conceivably most people are are riding ardound 20ish. Too many cassetes have unused 11 cogs for the amount of bragging people claim to ride like.

Jay Red
Jay Red
6 years ago
Reply to  ed

I spin out at 30mph riding a fixed gear with a 46×16. Practice more and try harder my friend. A 50t or even a 46t chainring paired to an 11t cog is plenty fast.

Dinger
Dinger
6 years ago
Reply to  ed

That’s an unlikely scenario for the rider that gearing like this is targeted at. These gear combinations are for bikes with bigger tires, ridden on slower surfaces.

JBikes
JBikes
6 years ago
Reply to  ed

I’m guessing the main reason you don’t see 32/50 or 30/50 is that it represents an incredibly large jump for the FD. Just going from 53/39 to a 52/36 or 50/34 is a big difference in shift quality since the tooth jump goes from 14 to 16. A 20 tooth jump may be feasible, but will be slow, clunky and could be prone to drops
There is an ultimate limit based on FD geometry (inner plate vs outer plate heights), but I don’t know what it is.

Tyni Tyres
Tyni Tyres
6 years ago

I suppose that with enough force it is possible to push a square peg into a round hole but I’m not sure if it’s the best solution.

AJ
AJ
6 years ago
Reply to  Tyni Tyres

Best comment ever

Joe Burton
Joe Burton
6 years ago
Reply to  Tyni Tyres

No pegs to push. Just unfasten your Shimano chainrings, fasten on the AB chainrings, and adjust your front derailleur height for clearance. So simple even a dummy like you could probably manage it. LOL

Lyford
Lyford
6 years ago

46×11 gives the same ratio as 50×12. Going from a 50/34 to a 46/30 is like shifting your whole gear range down a cog.

I’m not a wattmonster, I often end up on dirt roads, and I want a lower gear a lot more often than I spin out my 50×11.

Threeringcircus
Threeringcircus
6 years ago
Reply to  Lyford

Good point. Better chain line in most combinations, too.

Dinger
Dinger
6 years ago

That’s an interesting point because, “AbsoluteBlack’s solution is a patent-pending “offset chainring” solution that shifts both chainrings inboard by 2.5mm closer to the frame”.

Most all of the bikes that this gear combination will find its way onto are disc brake gravel/cx type bikes, all of which have 135mm or 142mm (same thing as far as cassette positioning is concerned..), making the ideal position for the chainrings 2.5mm *outboard*, not inboard. With this cassette position, and AB’s chain ring offset, they’re now at 5mm inboard of optimal chain line. This would probably would cause the most problems if cross-chained on the small ring.

Threeringcircus
Threeringcircus
6 years ago

If running 11 speed, which cassette would be ideal for something like these? Road cassettes don’t seem quite right (tight gaps on the high end) and MTB cassettes seem like overkill on the low end. Maybe an 11-34 is the sweet spot. I think these might be a good alternative for a drop bar 29er with an MTB cassette. For the gravel/cross 700c and 650b bikes, I think I’d be inclined to opt for 50/34 rings with an 11-36 or 11-40, using a $20 Wolftooth road link or similar to obtain lower gearing.

Dude
Dude
6 years ago

I find I need about 1:0.9 ratios on the low end, and about 1:4.2 is about as small as i want on the high high, for a bike to handle both steep & wet gravel and pavement rides decently. that means 46/30 with 11/34 is just about perfect, and works with regular road setups without getting super heavy or dealing with crazy long chains and roadlinks.

David
David
6 years ago

I have 50/34 and 11-36 on gravel grinder today. If I stay with 2x, I will be on a 46/30 and 11-34. The 11-34 fits in the medium rear derailleur range (my long cage with a 36 doesn’t shift nearly as well as my mid cage on a 32). These rings allow me to keep stock Shimano crank instead of replacing it with something more expensive and then still having to buy new rings.

BTW, f30r34 will be nice on those days when I get a little single track riding in on gravel bike with out having to resort to full squish mountain bike.

Lyford
Lyford
6 years ago
Reply to  David

30×32 gives the same ratio as 34×36, so 30×34 should be nice.

Technician
Technician
6 years ago

Kudos to PR team for NOT including the helmet in the AD. Helmet police can f^ck off.

Mike Williams
6 years ago

Very interesting…I was looking for options to convert an Ultegra 10 speed (50/34) to a gravel setup. If I could run the 46/30 with a 10 speed rear (a question for their tech support) I could make do with my current 11-28 cassette and the rest of my groupset. This would be the lowest cost (least hassle) option.

Or I could wait for Shimano’s new 105 offer with a sub compact crankset…which will be delivered by flying pig 🙂

JBikes
JBikes
6 years ago
Reply to  Mike Williams

Why don’t you just get an mtb crankset like almost all touring bikes run? I run a double on mine, works great. Just need a spacer for the narrower bb.

Joe Burton
Joe Burton
6 years ago
Reply to  JBikes

Because on some gravel frames with a braze on front derailleur you can get the front derailleur cage low enough and clear se enough to the MTB big chainring. Another issue with running a MTB crankset on a gravel frame is that the chainrings sit too far outside of the bottom bracket shell for the front detailleur to deal with. It may work on your frame, but that does not guarantee it will work on all gravel type frames.

Durianrider
Durianrider
6 years ago

I found this easy to fap to.

Cal Mickelson
Cal Mickelson
5 years ago
Reply to  Durianrider

What does fap to mean?

Braulio
Braulio
4 years ago
Reply to  Durianrider

Lmao is that actual durianrider?

HG
HG
6 years ago

It also has to do with Rear Derailluer chain wrap capacity

Jay G Marcotte
Jay G Marcotte
6 years ago

Trek owners wanting to gear lower may find this a worthy option, seeing as how no aftermarket crank/bb manufacturers I know of have made a subcompact that fits a Trek bb90.

satanas
satanas
6 years ago
Reply to  Jay G Marcotte

A Sugino OX601D or OX901D crankset will fit BB90 – they use a 24mm axle, same as Shimano. Stock rings down to 44×30 are available, and smaller will fit. The other problem is the front derailleur mount being too high, not easy to solve. The AB rings look interesting but there are cheaper complete cranksets with 46×30 rings, though not for BB90 frames.

Joe Burton
Joe Burton
6 years ago
Reply to  Jay G Marcotte

FSA makes 46/30 cranks in two different versions that will fit a Trek BB90. Any crank with a 24mm spindle or a 30mm spindle will fit the Trek BB90 so long as the crank spindle is long enough. FSA will work, Shimano 8000 and 9000 series cranks will work with the Absolute Black chainrings, even the Rotor 3D30 and 3D+ cranks will work with the Rotor 46/30 spider.

Chris
Chris
6 years ago

Or you could simply ride a road triple – 50t large ring, 30t small ring – with effectively better chain lines right through the range!
The only real downside is a (slightly) trickier initial set-up and the weight of a chainring…….

Corby
Corby
6 years ago
Reply to  Chris

And changing out shifters to triple if you are already riding a double. Triple shifter options on road /gravel bikes are also pretty.limited these days.

Andy Salmon
Andy Salmon
6 years ago

I have a triple on my road bike currently and on club rides averaging 17 to 18 mph I have no problem at all keeping up using the 39 and 30 tooth inner chain rings. For years I have wondered why as consumers we have this obsession with ever larger chainrings which we compensate for by using larger and gappier cassettes.

From my perspective, most enthusiasts are only ever going to spin out a 50 X 11 combination if their maximum cadence is in the low 80’s rpm range.

Having said all that, we can now see manufacturers looking to cash in on the super compact cranks with some highly inflated prices quoted for what seems to be little more than changing the BCD.

Michael Singleton
Michael Singleton
6 years ago
Reply to  Andy Salmon

Thank you. Are you using a triple on one of the press-fit bottom brackets, e.g. BB90?

Cal Mickelson
Cal Mickelson
5 years ago

Will these fit on a 2019 Giant Defy that has Shimano 105?

Jesse Boyd
Jesse Boyd
5 years ago

My thoughts on the AB SubCompact chain rings.

Running 48/32 on my Giant TCM Advanced SL and 46/30 on my Ritchey Swiss Cross Disc. I switched from 50/34 Rotor Q-rings on both. Being a heavier rider these chainrings have helped for both bikes. With a Wolf tooth I’m running 32 front 32 rear on the Giant. My group set is Dura-Ace Di2 9070. It works without any issues. I’m spinning now and climbing faster (better times). My Ritchey is running Ultegra 6800 – 30 front and 36 rear really helps on the steep fire roads and single tracks where I live. 25%-30% grades still suck but I don’t need to “paperboy” so much anymore. When I run my commuter set up on the Ritchey it’s 30/30 so I can take the hilly routes home for some extra credit. This is a noticeable improvement over my regular compact set ups. I’ve lost nothin on the top end either. I stay with the smaller guys on the hills, drop them descending and still pull them on the flats. Very satisfied.

Braulio
Braulio
4 years ago

(deleted)

Pedrito
Pedrito
4 years ago

Is there anything similar for poor people like me? I live in hilly brown people country and the 50/34 on my third-hand Shimano 105 5800 crankset isn’t cutting it.

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