I’m considering changing from Elixir Rs to SLX M666 brakes in an attempt to improve my stopping ability.

Magazine reviews seem to rave about the performance of the SLX brakes but I’d be interested to know what the real world views are like? Has anyone else swapped from Elixir Rs to the SLXs, and if so how do they compare?

Shimano Brakes > No brakes at all > Avid Brakes

I have Elixir R on one bike and SLX on another and there are two reason why I prefer SLX. Firstly, they are simply a much better brake and secondly, the ease of setup. Shortening the hose, bleeding, changing pads are just so easy on SLX/Shimano. Bleeding Avid brakes is just a gigantic PITA!

They’re great brakes. A little heavy, but great brakes.

Aside from the bleeding / maintenance aspects how does the stopping power compare? Is there a significant difference in the “throw-me-over-the-handle-bar” ability?

I had the SLX brakes on my commuter bike, at first they were superb. However over a period of 5 months the power just tailed to the point where i couldn’t lock the rear wheel with two fingers. Two sets of deore brakes previous to those did the same thing. Changing the pads restored there power, but not for long. The pads were getting contaminted with brake fluid, which became apparent when the rear slx brake ran out of fluid. It dampened my enthusianm for shimano brakes somewhat.

there was a batch of SLX/XT brakes with poor fitting/hose crimping apparently which would leak fluid. Very unlike Shimano TBH. And not affected my SLX M666s

Is there a significant difference in the “throw-me-over-the-handle-bar” ability?

If you want to be thrown over the bars then maybe stick with the Elixir, it’s one of the things I don’t like about them, sort of either on or off. SLX have a much better feel to them, better modulation, they’ll throw you over the bars if you want but not accidentally.

However over a period of 5 months the power just tailed to the point where i couldn’t lock the rear wheel with two fingers.

I’ve had Deore on my SS for the last 2 years and they still work faultlessly. Not had to bleed them at all just change the pads every now and again.

couldn’t disagree more. Elixirs (i have 2 sets of R) have better modulation than Shimano (tried 2 sets). i’ve also had Formula (unreliable, pad and rotor life a joke) and Hayes (wooden).

there are 2 problems with Elixirs
a) bleeding them properly is really hard, i’ve only just learnt to do this after 2 years. it’s the lever you need to do carefully. newer ones should have improved this and aren’t so f**ked by having some air.
b) not enough pad clearance, so avoiding rub is nearly impossible.
if you’re heavy, or don’t like maintenance, maybe shimano are better.

I have a new set of 666s on my HT. Frighteningly powerful compared with earlier Shimano and Hayes I have. Never tried Avids.

yeah see i don’t know why you want so much power. i don’t want to lock wheels or go over bars. what i want is fine control of braking and consistency, you get that with Elixir once you set them up right. it’s still one finger to lock wheels if you want to, you just need to pull quite hard.

Just put a pair of M666 on my 140 trail bike. They’re awesome. I can compare them with the Hayes Stroker Rydes (powerful but not very good for feel or feedback), with the Deore M595s on my HT (not as sharp in my opinion) and the Elixir Rs I had on a Boardman Hybrid. They were powerful, and about perfect on a roadbike! However, they didn’t clear the rotors and were forever whispering/catching the rotors which upset my OCD as I could never centre them for silent running.

Stick with the SLX, maybe a bit heavy, but love them to bits. They feel great once bedded in and bring my Clydesdale Carcase to a complete halt when required.

Mostly happy with my M666s, but I’m having to repress my OCD a bit as they seem to suffer the same problem as every hydraulic brake I’ve ever owned, which is that pistons don’t seem to retract consistenly, so the brakes that were perfectly set up, drag free at the start of the ride, will end up rubbing by the end. Haven’t actually checked if the calliper is drifting or the pistons, but from past experience I’d guess its the pistons…

Great brakes otherwise.

I had originally assume I could run new brakes with my existing Avid mounts and rotors but was told that will not work so my Elixirs are on their last chance as I’ve re-bled the rear brake, this time with the bike hanging on a hook to help the air escape, but failing this I will be going for the Shimanos.

I had a squidge on the Shimanos in the LBS and was really impressed with the lever feel, the Deore M596 look excellent value for money also and as far as I could tell similar to the M666 but without ice fin pads and a reach adjust thumb screw.

I like others have Elixir R’s on one bike (160mm FS) and M596 Deores on the other (140mm HT). When the elixirs are working properly they feel good and have plenty of power but they don’t work properly for very long after they have been bled. The elixirs have more modulation and feel along the whole stroke and the shimanos have nothing at the start and then you start too feel it about half way through the stroke. This may be because the elixir pads sit close to the disc and the shimano pads sit further away.

I have been converted to the feel and performance of the Shimanos and cant wait for the new Zee brakes to come out and they will be going on the FS.

A couple of mechanic mates swear by Shimano brakes, they say they have loads of Avid brakes coming back to be fixed but very few Shimano, both have shimano on all their bikes now.

Oh and Shimano brakes can be run with Elixir mounts and disc’s. Thats how I have them on my HT.

Assuming the Elixirs are having a good day which feel better to you the Deore’s or the Elixirs?

When using the Avid mounts have you done away with the cone washers and do you the bolt the caliper directly into the mount without any spacers?

If the Elixirs are on top form (very rairly) I would say they slightly edge the Deore’s. However like I said above it is hard to get them to work 100% and when they do it doesn’t take long for them to lose performance again.

The difference with the avid mount is in the calliper, the mounts are offset so there is room for the cone washers. This means that normal mounts can be used for avids and avid mounts can be used on other brakes. If this wasn’t the case Avid brakes wouldn’t work on post mount forks or frames.

The difference with the avid mount is in the calliper, the mounts are offset so there is room for the cone washers. This means that normal mounts can be used for avids and avid mounts can be used on other brakes. If this wasn’t the case Avid brakes wouldn’t work on post mount forks or frames.

This +1 the washers are part of the calliper not the addapter. Most 180/185/7″ addapters are identicaly sized, it’s the callipers that make upthe difference to fit 175/180/183/185mm rotors, and even then it usualy works.

As for Avid Vs Shimano. I’ve got the new XT and the Elixir 5 brakes.

Elixir 5 brakes, took a while to get the reliability, the seals on the rar calliper always seemed to stick resulting in the lever pulling to the bar, several bleeds later a few drops of fluid on the piston whilst pumped out and they’ve been perfect ever since. I know people who run them with the bite point ~3mm from the grips so they must be consistent as there’s no room to pump them upto pressure there! Great modulation, plenty of feel and more than enough power (untill I got the XT’s they were easily my most powerfull brake ever).

XT, masses of power, and if you ride motorbikes you’ll like the lever feel, there’s a little resistance as the cam pushes the piston in then the lever firms up completely, it barely moves. Takes a little getting used to in the car park, but on the trail where you’re not thinking about lever pull (just how hard you’re pulling it) it’s fine. Which means you can run them close to the bar which is nice for avoiding armp pump on long decents. Power is mahoooosive though, just tickle the levers to stop, this takes some getting used to. Definately not a brake you could drag down a decent, which is odd as the ice tech stuff should make it brilliant for mincers and dragging the brakes but the brakes seem set up for maximum power and braking as lat and hard as possible.

Ok – understood, thanks for the clarification; I did think it strange when the fella in the bikeshop told me they wouldn’t fit (but foolishly) I believed an “expert”

On the plus side following the bleed yesterday and resetting the bite point the Elixirs feel like they are new, here’s hoping they stay like that for at least one or two rides.

Next time the Elixirs fail I’m going for either Deore or SLX as looking after the Elixirs is too much like hard work.

Just been thinking the same thing, but thinking of getting rid of some Juicy’s.

I’ve got Elixir R’s on one bike & Juicy’s on the other and the Juicy’s are a nightmare. Wanna get rid and part of me is thinking I should get Elixirs as I will then have only one type of brake to worry about.
But, while the Elixirs are better, they are still a bit finicky.

I’ve been looking at SLX or perhaps Magura MT2/4. I had some Julie’s years ago and really liked them.