Formula Oro K24 Disc Brake System

4.78/5 (68 Reviews)
Weight : 395 grams MSRP : $239.00

Product Description

ORO K24: Powerful, Lightweight, and Adjustable!

Patented Feeling Control System (FCS) which changes the lever contact point!
Flip-flop lever design…are you Euro…or just Moto?
Removable lever clamp – no need to remove shifters and grips for lever removal.
Patented inline open system reservoir which makes for a super compact lever design.
Polyester braided hose for increased expansion resistance.
Nickel plated fasteners for increased corrosion resistance.

Post mount style calipers w/adaptors. No little shims to mess with: Quick and easy adjustments.
22mm pistons for the most stopping power of any 2 piston brake (testing done by Bike Germany in conjunction with a German University).
Quick and easy pad replacement.
Vented Caliper for increased heat dissipation.
Nickel plated fasteners for increased corrosion resistance.

-395g with 160mm rotors, IS adaptor and all fasteners included!
-Add 32g for 180mm rotor and 62g for 200mm rotors.

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Formula Oro K24! Click Here»

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Reviews 1 - 15 (68 Reviews Total) | Next 15

User Reviews

Overall Rating:5
Value Rating:5
Submitted by GT_LTS_XC_AM a Cross Country Rider from Pleasanton, CA, USA

Date Reviewed: February 17, 2012

Strengths:    Solid performance, light weight, easy installation, adjustable lever throw, adjustable pad play, flip lever, super braking power, modulation, two piston caliper, DOT 4 brake fluid, no squeak after bed-in and proper adjustments.

Weaknesses:    Organic pads are good for casual riding and trail riding, but fade severely when heated during long steep downhills. Replacement and aftermarket pads are not in stock at most local bike shops. The Formula brand is not stock on most facory bikes. Therefore, parts are harder to find.

Bottom Line:   
Super stopping power from cold to severely heated. Braking performance is very consistant. The lever always has a solid feel and modulation. The braking system allows for instant reaction to wheel lock up to rolling. This is essential for maximum braking power without flipping over. It is a brake system that build high levels of confidence. When you need brakes now, it's there, instantly. Smooth braking, does not grab, very controllable. My only weakness observed was the stock brake pads. The pads are great for most cross-country and trail riders. However, if a rider rides fast, more aggrssively, heavy, or in any of these combinations, the pads do not bite enough when hot. Additionally, the stock organic pads do not last a whole season of riding. Within a couple of months, the wear is excessive. I replaced the stock organic pads with EBC Gold series pads. The braking is even stronger and the wear is now under control. Time will tell, but so far the wear rate should be more that a couple seasons of riding.

Once you get used to the brake bleeding process, it is quite straight forward and only takes serveral minutes. As long as you do not open up the sealed system, it does not require frequent bleeding like other brands. Maintenance is very typical with disc brakes. Wash and rinse the dust from the caliper and discs. Prevent any contamination from getting onto the disc or pads. Parts are found mostly on-line and the pricing is reasonable.

Typical rides are in a excess of 1500 feet of decents. I bought this system because it was a 2009 model and was not the current product lineup for 2011. Hence the discounted price. Outstanding performance for the price. I full recommend the Formula ORO K24 disc brake system.

Expand full review >>

Favorite Trail:   Saratoga Gap

Duration Product Used:   3 months

Price Paid:    $130.00

Purchased At:   Universal Cycles

Similar Products Used:   Hayes, Avid Juicy, Shimano XT Disc

Bike Setup:   Replaced stock organic pads with EBC Gold sinther pads and 203mm Formula disc.

Overall Rating:5
Value Rating:5
Submitted by Michi a Downhiller from Austria

Date Reviewed: August 30, 2011

Strengths:    sollid power, super light, no maintainece needed for years, Dot4 brake fluid.

Weaknesses:    Tricky to bleed, same as elexier, code and many oher brakes taht copied formula construction.

Bottom Line:   
really the only bad thing I can say about this brake is that it is tricky to bleed.
Anyway, only needed once because Lufthansa broke the brake line on my flight to vacation, in about 4 jears uing it on first A Yeti ASX then a Yeti 303, Tomac Snyper, and now back on the ASX.

Why I rode so many Brakes? Because whenever I got a new bike I got sick about he brakes that where on it.
Non of tehm, except the hopes and eliexiers, where working as you would expect it from expensive and big brakes, so I keept moving my Oros from bike to bike and ended up buying a second set.

Actually Dot is awsome. You get it everywhere. Every gas station from deepest Africa to Beverly Hills carrys a bottle.
In case you really would need to bleed you can be shure you get what you need.

They also can be bleeded without a bleed kit, just two syringes will do. You can screw the directly into thread of teh allen screw taht closes the system if you choose the right size but make shure you don´t loos on of teh tiny o rings.
I know that sounds a little rough but it is possible and very cool if you sit in Marakesh with no bikeshop within the next 1000 miles.

Expand full review >>

Favorite Trail:   Schladming, 2Alpes

Duration Product Used:   More than 3 years

Price Paid:    $150.00

Purchased At:   forgot

Similar Products Used:   Oro 18K, Avid Elexir, Avid Code, Hope V2, Shimano Saint, Shimano

Bike Setup:   Yeti ASX, Mazocchi 66RC2X, XTR shifters and derailers. Raceface Atlas stem, bar, seatpost and cranks.
Sun singletrack rims with DT440 hubs.

Overall Rating:5
Value Rating:5
Submitted by Hora a Weekend Warrior from

Date Reviewed: July 26, 2011

Strengths:    Looks, finish, manages alot of high quality casting/machining without plastics found rampant on the likes of Shimano's servoware range..

Weaknesses:    Factory bleed. I didn't realise this before but another user has posted something similar- pistons don't push together inline so it actually needed a bleed before I'd even turned a wheel. If I'd have known this I'd have sent them back to be done at the shops cost. As it was I thought it was down to me learning 'finesse/something more classy'. Yes I know I should have known this and questioned/focused on it sooner.

Bottom Line:   
I'll give them 5/5 for now. However you really need to check to see if they are bled properly on your first ride as a proper shop bleed is bloody expensive.

Great product let down by a shoddy mechanic in the factory.

Expand full review >>

Favorite Trail:

Duration Product Used:   6 months

Price Paid:    $160.00

Purchased At:   markhoracekuk@yahoo.

Similar Products Used:   XT/(old) Saint, Hayes Mag.

Bike Setup:   Santa Cruz Blur4X, Fox 36 float, King, dropper seatpost etc.

Overall Rating:4
Value Rating:3
Submitted by Razzie a Cross Country Rider from Finland

Date Reviewed: March 2, 2011

Strengths:    Strong, reliable, light and easy to service

Weaknesses:    Levers, bleeding is tricky and balancing the caliper requires effort

Bottom Line:   
Braking power is sufficient and it only requires the lightest of pulls. With a 203mm front disc you get really efficient stopping power with not too much overheating.

After a long winter the brakes seem to have lost their "bounce" and feel a bit lazy. Bleeding them didn't help.
The levers don't fit my big fingers and no one makes replacement/upgrade levers for that model, what a disappointment.

Expand full review >>

Duration Product Used:   6 months

Purchased At:

Bike Setup:   Meta 6.1 Factory

Overall Rating:1
Value Rating:1
Submitted by Surophoto a Cross Country Rider from san juan

Date Reviewed: December 15, 2010

Strengths:    Great braking power. Light

Weaknesses:    difficult to bleed, worts bleeding ever

Bottom Line:   
Great Braking power but,
Extra difficult to bleed, I don't want them, even if they are free..

Expand full review >>

Favorite Trail:   monagas

Duration Product Used:   1 Year

Overall Rating:5
Value Rating:4
Submitted by robotpj a Cross Country Rider from Utarded

Date Reviewed: September 29, 2010

Strengths:    Plenty of adjustment, comfortable, great feel and power.

Weaknesses:    Replacement pads can be hard to find.

Bottom Line:   
I love these brakes. They've been 100% reliable for me since I got this bike. The brakes have plenty of adjustment and great feel and modulation. The only problem is that it can be hard to find replacement pads. The solution is to buy two sets at a time, which is what I always do now. The Formulas are on the expensive side but totally worth the money.

Expand full review >>

Favorite Trail:   Wasatch Crest

Duration Product Used:   More than 3 years

Similar Products Used:   Old Hayes, Hayes El Camino, Magura Louise, Avid Elixir

Bike Setup:   Bionicon Golden Willow with X9

Overall Rating:4
Value Rating:4
Submitted by bustamove a Cross Country Rider from SF bay area, CA

Date Reviewed: September 16, 2010

Strengths:    Good modulation, easy to service and adjust

Weaknesses:    Organic pads wear out fast, can be noisy sometimes. Price for a full setup is steep.

Bottom Line:   
Functionally, the Oro brakes work great. Swapped in EBC green pads and the squealing I hear is from the other riders around me.

As mentioned above, modulation is great and minimal effort is required. Liked them so much, I bought a 2nd set and installed them on my SS.

Expand full review >>

Favorite Trail:   the last one I rode

Duration Product Used:   More than 3 years

Similar Products Used:   Avid Juicy

Overall Rating:4
Value Rating:3
Submitted by Mattlock26 a Weekend Warrior from Mystic, CT, USA

Date Reviewed: September 11, 2010

Strengths:    Stopping power (power to weight ratio), modulation, feel

Weaknesses:    A little persnickety in terms of maintenance and parts. DOT 4 is maybe not the right choice for fluid for non-racers.

Bottom Line:   
When these brakes work, they are exquisite, and from my understanding, all Formula brakes are as well. Not surprising. They kill my old Juicy's, it's like they aren't even the same component it's such a difference. The Oro's can easily be run with one-finger technique even on some wicked steep terrain.

Now the downside: maintenance. While parts supply has gotten better, in the early days, parts were a little tough to get and at a premium. So, a hose length adjustment kit (three small parts) and a bleed kit (some lame syringes with a couple fittings) was like 70 bucks - crazy. And then there were the pads - also pricey and limited distribution. Like I said, it's better now, but still not big box availability - not that it needs to be, but, competition leads to lower prices, YRMV. Then there is bleeding and adjustment; a fine Italian art to say the least. It can be done, but you will need practice. That brings me to the brake fluid issue. I know that they like DOT 4 due to it's properties when heated, BUT, it is toxic, environmentally unfriendly and a mess. Yeah, if I'm racing and it matters, maybe I go for that last increment and run brakes with DOT 4. If I'm out knocking around in the woods, I think next time I will go with something much less innocuous.

Bottom line - excellent brakes but be aware that there are hidden costs and you better either have a great shop handy or be willing to learn how to maintain these if you want to keep them working at a level that justifies their price.

Expand full review >>

Favorite Trail:   Coaster - Big River

Duration Product Used:   2 Years

Price Paid:    $200.00

Purchased At:   Cambria

Similar Products Used:   Avid Juicy's

Bike Setup:   Yeti ASR

Overall Rating:5
Value Rating:4
Submitted by wilsonblur a Cross Country Rider from Littleton, Colorado

Date Reviewed: September 4, 2010

Strengths:    Power, modulation, feel, east of set up, light.

Weaknesses:    If you are an Avid user bleeding can be confusing. The directions stink, once its figured out though its darn easy. Not many places have ever worked on them and getting parts can be challenging.

Bottom Line:   
These combine two of my favorite brakes. They have the feel and modulation of the mini's and the power of the Avids. Other guys get on my bike and love the brakes. I can't say enough about how well the they work and give feedback to the rider. They seem to be able to keep the wheels perfectly at that point between lock up and stopping force. They never fade or get weak. We have several 3 mile plus downhill's here and with some really steep sections and they just work perfect. I took them to Winter Park yesterday and again after 5 runs they were better than when they started.

Here's how I bleed mine since its the only weakness I can find with them.

I followed the instructions listed here and it worked perfectly. Its not really that hard when you understand the principle behind their bleeding technique. Their instructions are overly complicated.

They are right bleeding would be easier if you took them off the bike. I managed with the rear on the bike and lever on an extra bar.

Fill both syringes half way up.
Take the lever off the bar and mount it or hold it so its vertical with the bleed port up.
Install one syringe on the caliper
Install the other on the lever
Push the fluid back and forth until there's no bubbles in the system
(Be careful not to empty either syringe or hold them in any position other than vertical)
Push the lever down and pull on the lower syringe 2-3 times creating suction to make sure all the air is out of the caliper. (this closes the reservoir and isolates the caliper for bleeding)
Then slowly push the fluid out of the caliper and slowly let the lever return to normal position.
Optional, you can push the fluid back and forth a couple of times just to make sure there's no air. End by pushing the most of the fluid to the lever to push out the old fluid.
Remove rear syringe and put bleed nut back in
Remove and top off lever and install bleed nut and you are finished.

Expand full review >>

Favorite Trail:   Golden Gate, Lair O' Bear, Dakota

Duration Product Used:   6 months

Price Paid:    $199.00

Purchased At:   Rocky Mountain Cycle

Similar Products Used:   Hope Mini's original, Avid Juicy 7's, Hayes, Magura Louise FR

Bike Setup:   SC BLT2, Talas 140mm, Dt 240 717, King, easton, race face deuc XC, nobby nic 2.4's, 180mm rotor in the front, 160mm in the rear

Overall Rating:5
Value Rating:4
Submitted by jrichendrfer a Cross Country Rider from Missoula, MT, US

Date Reviewed: June 1, 2010

Strengths:    Fantastic modulation system, great stopping power

Bottom Line:   
Its kind of like having the equivelant of anti lock brakes for your bike. I'm now able to use the front brake way more than before (was using avid bb7 mechanicals). Definitely worth the investment if you've got the money.

Expand full review >>

Duration Product Used:   3 months

Purchased At:   Trickle Down

Similar Products Used:   Formula ones

Bike Setup:   Jamis dakar xlt

Overall Rating:2
Value Rating:3
Submitted by ronanb a Racer from Edinburgh

Date Reviewed: May 12, 2010

Strengths:    Light, modulation, stopping.

Weaknesses:    Failed suddenly after 18 months.

Bottom Line:   
These were my all time favourites until they failed suddenly on a ride. A quick google shows that my failure is far from unique.

Basically the rod that adjusts the throw & FCS is threaded into the lever via a threaded cylinder. On a XC run I did my usual last minute progressive pull and got about 1/2 way to the bars when suddenly the lever popped all the way back to the bar and braking reduced to maybe 50%. Fortunatly there was a run out and no damage done.

I was sure I had a fluid leak but it turned out to be this bolt had stripped it's threads (you cant overtighten it - its just an adjuster). So the lever was pushing on the rubber thingy(?). Without the threads the lever lost maybe 50% of its use.

What bugs me is that I never change the reach or FCS yet it just fails all of a sudden like after a normal 16 months use (maybe 4000km).

On my other bike I use SLX and never had a problem (but they are a bit heavier). I think I'll replace them with SLX / XT.

So overall - I loved them but they gotta go.

Expand full review >>

Favorite Trail:   Innerleithen

Duration Product Used:   2 Years

Price Paid:    $100.00

Purchased At:   online

Similar Products Used:   Shimano SLX, Avid Juicy 7

Bike Setup:   Whyte 19

Overall Rating:5
Value Rating:4
Submitted by Rqukrawler a Cross Country Rider from Central Coast, CA, USA

Date Reviewed: November 19, 2009

Strengths:    Superlight and compact, no brake fade, amazing stopping power, quiet, self adjusting, adjustable lever throw and modulation, split clamp on bar for removal without disturbing grips.

Weaknesses:    Bright white color... on a mtb? A bit pricey. Hear they are a PITA to bleed and the instructions seem to back that up, but haven't tried myself yet. Need a $30 kit to bleed.

Bottom Line:   
I'll need to compare these to my old Deore M525's... the only other disc brakes I've used. But wait, there is no comparison!

The formula's have zero fade, predictable modulation and incredible stopping power. I'm a one finger brake lever guy and even on the longest decents I'm still only using one finger. They installed in minutes and I have not had to adjust them once. Super compact. They unclutter the bars nicely. My buddies thought they were cable actuated because the levers are so compact.

My old Shimano's would fade on medium to long decents to the point of not being able to lock the rear tire. Half way down I'd have to start using 2 fingers to get enough brake. I had to adjust them regularly to keep them from rubbing the rotors. None of these annoying problems exist with the Oro's. I'd buy them again in a heartbeat.

Overall 5 flamin' chilis... I'm going with 4 for value only due to the relatively high price.

Expand full review >>

Favorite Trail:   Anything with singletrack

Duration Product Used:   3 months

Price Paid:    $280.00

Purchased At:   Ebay baby

Similar Products Used:   Shimano 525's, V-brakes, old canti's back in the day

Bike Setup:   08' ETSX-70; plenty of goodies

Overall Rating:5
Value Rating:4
Submitted by mb323323 a Cross Country Rider from Marin

Date Reviewed: October 3, 2009

Strengths:    Excellent modulation w/o giving up power. Feel like power brakes. A monkey could change the brake pads it so easy!!

Weaknesses:    Somewhat pricey but certainly worth the money. Only color available was white. I'm digging for something here because they've been so good and it's my nature to critique things.

Bottom Line:   
I wanted to just chime in after about a year of using these. I ride 5 days a week and the ride usually includes a 2500 foot decent. The K24's are literally superior to all other brakes I've used.

Also, I've gone through some brake pads (they usually last 3 mos) and I like the organic pads best. I felt they have the most stopping power.

These brakes have very little if any fade at all during my 2500 foot decents.

Also took the bike to Downieville this Summer and had no fade problems what so ever.

I can be very critical of the things I buy for biking but these have been very good and I just don't have anything negative I can say about them.

5 chilis for overall and 4 for value just because $330.00 for bike brakes is insane. Isn't it?? I bought though so, oh well.


Expand full review >>

Favorite Trail:   Anywhere on a trail

Duration Product Used:   1 Year

Price Paid:    $330.00

Purchased At:   LBS

Similar Products Used:   Avid cable, Hayes, Magura Louise, Avid Juicy. Magura's best of this group but not as good as the K24's.

Bike Setup:   Turner Flux w/ Fox, etc

Overall Rating:5
Value Rating:5
Submitted by beatfarmer a Cross Country Rider from Appleton, Maine

Date Reviewed: October 2, 2009

Strengths:    This forum was a major factor in choosing these brakes to replace the BB7's that my bike's previous owner installed. I love these brakes. Installation took about 15 minutes for rotors, calipers, and adapters. I love these brakes. As other reviewers have noted the power and modulation are exceptional. The only time they've made any noise is when the rotors are wet, though it's only ever been a light squeak and stops within a couple seconds of braking.

The FCS system is pretty nice in getting the front and rear to a similar response.

Even with an Alley Cat trailer with my 6 year old, the combo of which adds about 100 pounds, these brakes effortlessly stop the bike.

Positioning on the bars is great with Sram X-9 triggers. The split clamp is a great design feature. Levers are great in that I brake with my middle finger and have them mounted inboard of the shifters. Very comfortable set up.

Weaknesses:    I'm not sure if this is unique to Formulas, though I need to be very careful when putting the wheels on the bike to not catch the pads with the rotor. If I do they come out of alignment and rub. Not a huge deal since it only takes an allen wrench and about a minute to realign the caliper.

Uses DOT, I was really hoping to be running mineral oil since DOT fluid is so toxic.

Bottom Line:   
These brakes are awesome, especially since I got front and rear including rotors and adapters for $260. Hopefully they'll stay this nice, be easy to work on, and the pads won't wear out too quick.

Expand full review >>

Favorite Trail:   Snow Bowl

Duration Product Used:   3 months

Price Paid:    $260.00

Purchased At:   online

Similar Products Used:   Hope Mini, BB7, Juicy 7

Bike Setup:   Turner 5 Spot, King, Fox, Sram, etc...

Overall Rating:4
Value Rating:4
Submitted by wenisman a Weekend Warrior from london

Date Reviewed: September 28, 2009

Strengths:    great modulation, lever feels positive and tracks fingers well, easy setup, loads of power.

Weaknesses:    levers are a little long (i crushed my fingers with 1 finger braking, so back to 2 fingers), parts...

Bottom Line:   
this is going to be a comparison between the hope mini monos and the formula k24's as i bought both at the same time and they are about equal in terms of price paid and features offered.

the fitting of the k24's was alot easier than the hopes had been, this is due mainly to my fault as the hope were standard mount as i mis-ordered. that said the formulas really are a 15 minute fitting job if you have the right tools and know a little about bikes. but all post mount brakes will be this easy.

the first test came on the trails, the formulas and the hopes both performed an admirable job on the trail. both brakes have awesome stopping power and will pull you up as required, but the formulas do seem to have that little extra bite and control which is really only noticable in the muddy or rocky off camber corners. after a while the hopes started a little squeally grumble but this was due to a little damp and once reshimmed the grumbling stopped. the formulas did remain quiet and responsive and worked flawlessy for well over a year... really did fit and forget them. but the hopes did that too excluding the shim to stop the squeal.

i found the formula levers a little to long, so that if i used 1 finger to brake i would end up crushing my fingers. no amount of playing with the lever adjust or the grub screw fixed this, however the hope levers worked beautifully and i never experienced the finger vice as i did from the formulas.

the ultimate test came when i took my rocky etsx away for a long rough trip... and the abundance of parts and how easy they are to maintain came into question. after one particularly natsy crash i bent a lever, but on the forumlas these were not easy to get new parts and the process of replacing them was actually a little painful. also the pads are tough to get a hold of, i ended up having to hack and file some hope mini mono pads to make them fit until i could get real formula pads. again these are also my fault but should be a consideration when buying...

then somehow after 18months they had an air bubble in the system... i really should have bled them previously but they still worked flawlessly and my hopes worked without a rebleed. but this actually incurred another expense, the bleed kit was not cheap and i had to get an avid one. the bleed process is straight forwards, again takes a little bike knowledge however i personally find bleeding the hopes to be an easier and more drip free task. plus i dont need to buy a specialist bleed kit, i just need a little plastic hose, spanner and my allen key.

my overall impressions of the formula is that its a great system, easy to fit and will work extremely well in all conditions. but if you do get these brakes (or any formula) you will need to plan ahead. get spare brake pads, buy a bleed kit, and if anything goes wrong with the lever or caliper you are going to need to send them back. if you can live with a little less modulation and power but easier maintainence and hope provide possibly the best service known to man... then hope is the brake for you. all in all if you ever do a long distance trip where you will go days without visiting a city get the hopes... the forumals will last but if they go wrong you are gambling that you can fix it.

Expand full review >>

Favorite Trail:   all single track

Duration Product Used:   2 Years

Price Paid:    $400.00

Similar Products Used:   hopes (original m4's, m4 monos, mini monos), avid juicy (5, 7)

Bike Setup:   rocky mountain etx-s70, all blinged out...

Reviews 1 - 15 (68 Reviews Total) | Next 15

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