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Initial Review: Formula’s updated RX disc brake

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Billed as the perfect brake for XC or all mountain/enduro use, Formula’s RX has long been a solid aftermarket choice and great OEM score.  For 2012, the Italian-made brake gets a new flip-flop master cylinder and the core brake comes in at 242g (plus ~100g for a rotor)- not at all bad for $185.  Formula’s a la carte pricing makes pad contact adjustability, tool-free lever position, and all-steel or dual-material rotors optional, allowing riders to buy as much–or as little–fiddleability as they would like.  After a couple of months on my go-to trail bike and an Alpine rental, how have Formula’s value brakes fared?  Hit the jump to find out!

With a couple of years on the first-generation RXs, I’ve been more than pleased with their performance.  On XC and trail brakes, with 180mm on down to 140mm rotors, the previous generation have been workhorses.  They’ve only required bleeding about once per year- far less often than some brakes and about on par with the best.  The second generation maintains the first’s firm but controllable lever feel with plenty of modulation and the ability to really work the edge of traction.  They don’t have the gobsmacking power of Shimano’s XTR Trail brakes (which weigh within 5g of the Formulas but cost considerably more) but come out a bit ahead of Magura’s MT6s.

Our test samples came pre-bled and fitted with Formula’s Feeling Control System (FCS) adjuster, which allows for easy free-throw adjustment.  Though it adds only a few grams, I’m not someone who ever really wants more free throw at the lever, preferring instead to keep the levers comfortably close to the bar and engaging when the flat of the blade is parallel with the grip.  During my stay with FlowMTB in June, my rental came sporting FCS-free RXs- and I never once missed the $45 upgrade.  Similarly, I’ve never been overly burdened by having to reach into my pack for an Allen key to adjust lever position, so foregoing other brands’  tool-free lever reach adjustment was never missed.

For our review, Formula provided their 180mm and 160mm (95g actual) dual-material rotors.  Not only do they save 20g apiece over the company’s steel rotors, but the aluminum carrier is said to improve heat dissipation and reduce noise.  In my experience, dual-material rotors are seem less prone to warping from uneven bolt torque.  Though they certainly are less squeal-prone than the older steel rotors I have also been running, the fact that the $40/$50 (160mm/180mm) steel rotors are so good and so light make the extra $50 per wheel a tough sell for anyone but the heaviest riders, those who routinely see long descents requiring lots of braking, or those who just can’t stomach a bit of squealing from time to time.

Formula’s choice of steel Allen hardware for lever and caliper mounting is welcome after spending time with (and stripping) lighter brakes’ aluminum nuts and bolts.  The RX’s 22mm composite pistons are the same size as those used in Formula’s R1 superbrake, with which the RXs can share pads (with steel backing plates here, as opposed to aluminum).  In fact, it’s the R1’s aluminum-backed pads save a decent 15g per wheel: racers on a budget would do well to pick up a pair of RXs and upgrade to the lighter R1 pads once the stockers are spent.

In short, the basic RX comes with everything it needs and nothing it doesn’t.  My experience with the original RXs has been excellent, and after a long-ish break in period, the new model suggests more of the same.  Take it easy on the options and the price is more than competitive.  The ability to purchase the lever and caliper assembly separately also makes the Formulas an ideal upgrade for tired, heavy, or high-maintenance brakes while keeping stocking easy for shops.  Only a season’s riding will tell for sure, but the RXs are looking like the mid-priced brake to beat- and can even go toe-to-toe with pricier options.

marc

formulabrakeusa.com

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Olafur
Olafur
11 years ago

My 2010 RX brakes are still running like champs, after countless trail rides, several bike park runs and a week in the alps. Only needed a bleed once (last month in fact), instantly felt like new after that. It’s kind of ridiculous how little I have to think about them.

hugo
hugo
11 years ago

hate the lever design!!!can’t brake nicely with descents are long! rather use shimano!!
very close to bmx designs and more effective!

Andy
11 years ago

Mid-priced? As horrifically expensive and about the same price as XTR? (raises eyebrow).

Andy

Bill Beeper
Bill Beeper
11 years ago

I have been using Formula RX brakes since 2010 and used Oro K24 for 3 years before that. I’m pretty familiar with Formula’s brake features. To me, the discussion of lever free throw is confusing.

In my experience FCS adjusts modulation and pad contact, while the grub screw (or TFRA add-on) would control lever position relative to the handlebar. I don’t think of FCS as having to do with “lever free throw” related to how close to the bar my lever is. That seems controlled by the grub screw/TFRA. To me, FCS makes the brake feel either more or less wooden, either more or less on/off.

My standard RX brakes lack both TFRA and FCS add-ons, and they feel more on/off than my Oro K24s did. The K24s had FCS adjustment and the modulation was noticeably different depending on where you adjusted the little lever.

The shortcoming of the RX is that it’s tough to get the lever close to the handlebar. It helps to bleed the brake with a business card or two shimmed between pad(s) and rotor. Some people talk about bending the lever, though I’d prefer the bleed trick over fatigue-stressing the lever.

Mindless
Mindless
11 years ago

Finally. Their brakes are fine, but 180mm rotor was made of cheese. I had to swap it to a shimano one.

This should keep it straighter longer.

MsC
MsC
11 years ago

What rotors are being used on the second and last pic?

MissedThePoint
MissedThePoint
11 years ago

Hmm, I have an old set of Formula R1 boxed up. They were too strong for my super lightweight XC bike. I just got a 29er trail bike equipped with ’12 XT brakes… hmm, should I throw on the Formula R1s, or sell ’em for maybe $300-350 for F&R? I couldsell the XTs for maybe $200 for both F&R with rotors, if I decide to use the R1s.

Hmm, with how good XTs are, I think I should keep ’em and try to recover some money on my R1s.

Mike
11 years ago

These RX brkes are excellent.
Light weight and very well designed. They are powerful and nicely modulated. Bedding in is important but once this is completed the brakes work faultlessly . I have had no problems with the stock organic pads. The build quality is remarkable for the price, easily as good as XTR but cheaper, virtually as light and more powerful.

Mark
Mark
11 years ago

Great high quality well engineered brakes. Typical high quality Italian gear. Very powerful in the 180/160mm rotor sizes, with plenty of feel. The weight is very low and reliability is fit and forget excellent. The colours and finish is boutique bling without the high price tag. No lever issues or rotor issues either. Organic pads have loads of power and semi sintered are eye popping.

j.d.
j.d.
11 years ago

There’s alot of comparisons between post- 2012 xt’s and Rx’s.

1.XT brakes, with rotors and mounts, cost as much as a set of Hope’s. Unlike Hope’s, they will be worth pennies in a couple of years if you have to sell them for replacements. There are good deals on RX’s around, plus they hold value better than Shimano. Thats from experience.

2.RX’s. when set up and bled. are stupidly powerful. The final third blows my Hope m4’s out of the water.

3.XT’s have a plastic resevoir cover circa 1977 Star Wars toys. Its very shiny, but that won’t help if you crash and rip it off. Can’t happen? It did to my Hope’s: the aluminium cover meant I only lost the Hope logo and black paint.

4.XT’s have cheap hoses. RX’s do not.

5.Do you want to bleed your new disc brakes the day you buy them? Don’t buy meter long front XT’s if the answer is no. My RX’s were running in half an hour of recieving them. Shimano have sold alot of bleed kits with that meter long hose length blag!

I looked at both. Im very happy with my choice.

Dan
Dan
10 years ago

I agree with all j.d has said. My LBS guided me to the Shimano XT brakes and I have been disappointed …..with poor power and bleeding issues. These Formula RX brakes have taken no time to fit and once they are bedded in the power and modulation are just superb. No reliability issues either as the design and build quality are excellent. There is nothing to match them at this price and the really expensive brakes are barely any better.

Jason
Jason
10 years ago

New Shimano xt brakes are great. If having bleeding issues, your lbs or you need to learn how to keep them working proper. I bought my, trimmed the hoses without bleeding and have had phenomenal service out of them. I will make no arguments that Shimano doesn’t cut corners.

Aaron
10 years ago

I have to agree with the past few comments my formula Rx’s (2011) haven’t required bleeding once and they are two years old now with 5K+ KM of riding on them.

The lever throw from nothing to full power is fairly small but still retained great modulation. All in all I wont be swapping them out for anything, and nothing other else will be going on my next bike… (except maybe R1’s..)

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