Mtbr's 2016 Winter Biking Gear Reviews and Roundups





Shimano SLX BR-M666 Disc Brake System

4.85/5 (13 Reviews)
MSRP : $152.99

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Product Description

The new SLX disc brake borrows heavily fromThe XTR line such asThe IceTechnology which reduces heat buildup.Other features: Oversized full ceramic piston for optimized light weight, rigidity, and insulation One-way bleeding--easy and clean bleeding system Heat resistant F03C metal pad included (IceTechnology) Short stroke Servo Wave mechanism for quicker engagement and higher level input 2-finger brake lever with ergo pivot Dial adjust lever reach Ispec compatible Includes pr

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Reviews 1 - 13 (13 Reviews Total)

User Reviews

Overall Rating:5
Value Rating:5
Submitted by Tim Esposito a All Mountain Rider

Date Reviewed: April 17, 2014

Strengths:    Based on 2 years of riding thus far, I don't think you can go wrong with these grabbers....They hold up, they are easy to maintain, they don't cost that much, they flat out work. No fade,

Weaknesses:    They don't look good. Need a black finish.

Bottom Line:   
I tip the toledo's at 240... they stop the bike (185's front and rear). No maintenance thus far. No fade at all for me. The cost is very good. If your looking for an upgrade, these are the ones to look at. I had Avids, they worked well but needed adjustment from time to bad but the SLX....perfect. I have a fleet of niners...2 with SLX and one with Xt's... not a real big difference to me there either. I put my money into the XO 1x11 (I also have the XX1 1x11) not a big difference there either. SLX's are the best bang for the money and they last. You can spend big $$ for brakes but you can save a butt load (there's 10 butt loads in a Sh#t Load)...One finger stopping, light weight vs. all.

Expand full review >>

Favorite Trail:   Any thing at all..climbing gets it!!

Duration Product Used:   2 years

Similar Products Used:   Avid's, Xt's, CR's

Bike Setup:   XO 1x11, XX1 1x11

Overall Rating:5
Value Rating:5
Submitted by Lance Armstrong a Racer

Date Reviewed: November 16, 2012

Strengths:    Everything!

Weaknesses:    I guess they could have given it a nicer finish like xt or xtr

Bottom Line:   
Same power as XTR. 1/3 the cost! These brakes in my mind are the best brake in the world vs. cost! Great one finger levers, easy adjustment, awesome!

Expand full review >>

Duration Product Used:   Nearly 1 year

Similar Products Used:   Shimano M505

Overall Rating:5
Value Rating:5
Submitted by daniel harvey

Date Reviewed: October 18, 2012

Strengths:    efficient, affordable, light touch

Weaknesses:    none so far

Bottom Line:   
Been a BB7 guy for years. Will have trouble using anything but Shimanos now on a bike that finds itself pointed downhill much of the time. These brakes are powerful and only require a light touch. I guess I'm stating the obvious regarding hydraulics. I think the BB7s are still great for my SS and more XC bike, but my Yelli Screamy would not be the same without the Shimanos.

Overall Rating:5
Value Rating:5
Submitted by 666Shifty a Downhiller

Date Reviewed: August 28, 2012

Strengths:    -Great stoping power
-excelent modulation when you get used to them (they are so strong compared to the Avid Elixir that you need some time to get used to them),
-cheep brake pads (even the ones with cooling ribs),

Weaknesses:    -no free stroke adjustment, you have to buy XT for that (I think you dont need that)
-not so strong with avid G3 rotors, It is big difference when you try shimano rotors (normal ones, not ice-tech)

Bottom Line:   
I think Shimano SLX M666 are the best mid-range all mountain/enduro brakes. They are stronger than Avid Elixir, cheeper, you have fewer problems (or in my case none). Brake pads are cheeper, they last longer.... The only weeknes is that you need Shimano rotors (works better than with other rotors)

Expand full review >>

Price Paid:    $200.00

Purchased At:

Similar Products Used:   Elixir CR, Formula The one, Avid code (old), Avid juicy...

Bike Setup:   Specialized enduro comp

Overall Rating:4
Value Rating:5
Submitted by Front Range Rider

Date Reviewed: August 21, 2012

Strengths:    Incredible stopping power, quiet, modulation, run very cool (no fade), price, simple reach point adjustment, easy setup (alignment/ no rubbing)

Weaknesses:    cotter pin to hold the pads in? just seems so cheap. The hole is threaded so there must be a bolt for it somewhere out there.

Bottom Line:   
Picked these up from Blue Sky for $89 a piece. Ice Tech XT Front 180/ rear 160 for $45 and $40. As others have stated these brakes inspire confidence. I had a set of avid Elixer R's (185mm fr and rear) that worked well enough when they were working...only they were never working. Squealed and needed bleeding too much to tolerate. The SLX setup was simple, I didnt have to resize the cable or bleed the cable. Having a proper in/lbs torque wrench would be a good idea, though not at all necessary. Break in of the pads seemed very quick and power increased quickly. These are true one fingers brakes. I dont even think about them except that I noticed how much quicker and smoother I stop now. Locking up the rear wheel requires no effort but still requires intention. The modulation is excellent. One thing I did notice is that these brakes will illuminate flaws in your wheels. I have heard spokes make noise on the drive side under heavy cranking but never from brakes. These do! Another user said his levers would extend down on downhills due to the spring not being strong enough. I can see how that could happen as just tapping the lever in the opposite direction will move it forward, however, it has never happened to me. The 'ice tech' rotors and cooling fins really do the trick. I have yet to experience any brake fade on any of my rides. Im 220 and have ridden the falcon trail and monarch crest so far on these brakes. Very impressed with these brakes as they take my mind off of brake issues and back onto the trail. trek remedy 9.8 for reference. Only gave 4 chilis overall due to the cheeseball cotter pin instead of a real bolt.

Overall Rating:5
Value Rating:5
Submitted by artypuma

Date Reviewed: August 8, 2012

Strengths:    great power, quiet

Weaknesses:    none so far

Bottom Line:   
6'-4" at 296 lbs, I have so much more confidence in my stopping ability over V-brake technology.

Overall Rating:5
Value Rating:5
Submitted by Tit a Downhiller

Date Reviewed: July 30, 2012

Strengths:    Great power, great modulation (compared to m810 saints), superb heat dissipation, nice feel of the quite short levers.

Weaknesses:    Haven't found one yet. Maybe the split pin that holds the pads in looks kind of cheap but works. Some might say that there is no pad clearance adjustment, but you have XT's for that.

Bottom Line:   
The Sram 9.0's I had on the bike before just were not cutting it for downhill. I was always dragging my brake (and by doing that overheated them), Formulas were a bit better but pad's and adapters were hard to find (I had to make my own adapters for the most part). When I tried my friend's saints for a few runs I decided I needed new brakes. Second hand saint's were running a just bit more expensive than new 666's and I was sceptic if brakes as cheep as this will work on a heavy downhill bike. But then the shop where I got them had a sale on them and after talking with the owner who also uses them on his own bike I jumped on the opportunity.
Since I'm on a budget I got Hayes V8 rotors to go with them (had good luck with them before) which wore more than half as expensive as even the old XT rotors, let alone new Ice Tech rotors.

Installation was a snap (the clamp lever mounting is a great thing). Initial brake in period was quite short.
First few runs were on a short local DH track where I immediately felt more comfortable on the bike.
The real test was this weekend at Bike park Javornik which is known to be quite hard on brakes. They worked flawlessly, didn't overheat once, had terrific one fingered stopping power, no change in feel the whole day and pad life seems quite good to (using stock finned metallic pads I can't see any usage at all for now). For me personally they have a bit more modulation than 810 saints and just as much stopping power. Even my friend with the saints said that the lever feel is maybe a bit better.

So in short: SLX BR-M666 (and the new 675 which have just a few cosmetic changes and are 10g lighter) are a superb brake, for a great price (paid 74.90€ for each, under 200€ for both with rotors and adapters). They can stop a heavy guy on a downhill course with 203mm rotors without a problem, I'm sure they would be superb on AM bikes even with 180/160 rotors.

Expand full review >>

Favorite Trail:   Javornik bike park

Duration Product Used:   Around a month

Price Paid:    $92.00

Purchased At:   http://www.kolesarsk

Similar Products Used:   On mine bikes: Sram system 9.0 (Gremeca System 8), XT M755, Formula Extreme DH (4racing DH), Hayes HFX 9 HD, Giant MPH 1 and 3, Pro Stop

Just riden on friend's bikes: Shimano Saint BR-M810, Magura julie hp

Bike Setup:   MSC F-1.0, 07 Marzocchi Super T RCV, mix of truvativ and shimano gear, Maxxis Minion DHF 42a front and rear, hayes V8 203mm rotors.

Overall Rating:4
Value Rating:4
Submitted by SMP1971

Date Reviewed: June 6, 2012

Strengths:    Build your confidence.

Weaknesses:    My front started squeling and lost power after the first 5 rides. I have not switched the pads yet and i'm hopeing this will do the trick.

Bottom Line:   
Like every one has said thes brakes are a very good product. They cam stock on my EX 8 and if new pads fix my problem i will be happy again.

Overall Rating:5
Value Rating:4
Submitted by casrec

Date Reviewed: May 28, 2012

Strengths:    Great Power, Good modulation, one finger braking, very little if any fade!!!

Weaknesses:    Looks, feels like lever could brake easily(but i am sure it can't)

Bottom Line:   
Replaced my stock Hayes Ryde with these guys. They are leaps a bounds beyond the Hayes. Great Power and modulation. Lever feel and feedback is good as well. I gave them a four on value as I felt they should have come with rotors and not that it really matters, but a little more effort in aesthetic would have been nice. All in all though these are some of the best brakes for the money, well worth it and I would recommend to anyone.

Overall Rating:5
Value Rating:5
Submitted by Timmyt a All Mountain Rider

Date Reviewed: May 23, 2012

Strengths:    Everything. I can't rate these brakes high enough.I've just built a new hard tail with a generous budget, and these are the most impressive thing on the bike.The stopping power is stunning, coming from some single pot deore stoppers even with one finger i have to be gentle.I did consider the xt model, reading around the reviews where so positive and also these are the same calliper.

Weaknesses:    None, did have to bleed the front but it was really easy using the screw in tank

Bottom Line:   

Expand full review >>

Price Paid:    $160.00

Purchased At:   chain reaction cycle

Similar Products Used:   Avid, Deore

Bike Setup:   Ragley pig x, Rockshox sektor,Sram x9, Mavic cross line

Overall Rating:5
Value Rating:5
Submitted by rob1208lv a Cross Country Rider

Date Reviewed: May 8, 2012

Strengths:    good modulation, easy to set up, no squeal, true 1 finger braking

Weaknesses:    doesn't come with rotors.

Bottom Line:   
These are the best value brakes out there by far. Super easy to set up no squealing even when wet, very responsive and a true 1 finger brake. They are relativity light and priced great. I would have paid more for these brakes. I paired these with Hope floating rotors and just love them.

Expand full review >>

Price Paid:    $100.00

Purchased At:   tree fort bikes

Similar Products Used:   Avid bb7, avid juicy, Avid elixir

Overall Rating:5
Value Rating:5
Submitted by mtblol a Weekend Warrior

Date Reviewed: April 16, 2012

Strengths:    Very good modulation, brake lever is ideal for 1 finger braking, very powerful stopping power. No loud obnoxious squeaking noises that plague the avid elixir brakes. These can be had for under $200 both front and rear brake!

Weaknesses:    They came stock on my Fuel ex 8. My rear break died on the second ride, my shop warrantied it on the spot. No problems since! (200 miles on the new brakes and I love them). They weigh slightly more than avid elixirs.

Bottom Line:   
These brakes have a really great feel to them. They have very comfortable levers designed for 1 finger braking. And rightfully so, these brakes stop my 200lb with EASE. Modulation of the braking power is excellent too. They are as cheap as the elixir 3s and they're better brakes than the elixir 7s. You wont find a better brake system for 200, period.

Expand full review >>

Similar Products Used:   Avid Elixir 3, 5, 7
Giant ROOT
Juicy 5
Elixir R custom
Shimano M666 brakes

Bike Setup:   fuel ex 8

Overall Rating:5
Value Rating:5
Submitted by XCSUR4 a Cross Country Rider

Date Reviewed: April 10, 2012

Strengths:    value, stopping power, feel, response, installation/setup, radial mount levers, looks,
fade free, sintered pads, extra fittings, minimal break in period.

Weaknesses:    none.

Bottom Line:   
These brakes Rock! Incredible 'bang for the buck'.
Even with regular XT rotors, these things have awsome stopping power and great modulation.
I am predominantly an XC rider, so I didn't bother with the IceTech rotors because I just wanted reliability for the long term (read: too many components). Installation, and shortening the brake lines was simple (with parts/tools provided). The break in period was almost un-noticable; In fact, after 75 miles, they have required NO adjustments.
Anyone looking for Performance with Value should buy this braking system. Like the XT units, these have Forged Calipers, Ceramic Pistons, and Sintered pads; So save your money !
Thanks to my brutha Nelson @ Cycle Solutions for a great deal.

Expand full review >>

Favorite Trail:   3stage

Price Paid:    $330.00

Purchased At:   Cycle Solutions

Similar Products Used:   '07 Hayes NINE(suck). Avid Juicey5. XTR Vbrakes(great). XT Vbrakes. XT canti's.

Bike Setup:   '07 GIANT Anthem1. Fox-32-F100. New XT drivetrain, Brakes & Mavic321 rear, 2012.
RaceFaceXC Evolve crank. Kore/Easton flatbar w barends. '03 BodyG saddle.

Reviews 1 - 13 (13 Reviews Total)

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