SLX M665 brakes for DH?

[scottishmark]

Lots of light people who didnt do long runs. All the people I know on them were happy at first but then prefered their new other brakes that faded less.

Any 2 pot brakes that arent v2s, ones or gustavs (ie power wise in the realm of 4 pots) fade unless you use a high quality dot 4/5.1 fluid. In case of mineral the boiling point is close to 70deg lower. Thats 25%

sorry, not buying that one. i know several people that have done seasons or live in the alps and Saints (M800s) have been the brake of choice over Hope 4-pots

Ive tried Xts and SLXs and they are not the most fade resitant brakes, my oros with rbf 600 faded much less.

stop dragging them then

Baring in mind that both myself and the other Mark weigh about a bag of sugar each, they'll likely be absolutely fine

[scottishmark]

Mark, if you dont need rotors they're £125 a pair on Merlin just now

[norbar]

sorry, not buying that one. i know several people that have done seasons or live in the alps and Saints (M800s) have been the brake of choice over Hope 4-pots



stop dragging them then

Baring in mind that both myself and the other Mark weigh about a bag of sugar each, they'll likely be absolutely fine

Did you read my post? Ive said V2s and not m4s (the 4pots - these are bad) . I was talking about v2s - the big 2 pots. The m4s - 4 pots as Ive said in my previous pots ARE WEAK but they are trail brakes. Its closer to running XTRs or Magura Martas.

[Udi]

Norbar -
You have the wrong idea here. Brake fade has nothing to do with fluid, ~95% of the time.

The only way fluid is really going to cause fade is if it boils, and then your lever will come to the bar and you will have no brakes. Aside from that the only thing it can do is get thicker or thinner, which won't really affect anything but lever feel.

Brake fade will be a result of pads, rotor size, and obviously the greater the overall power of the brake, the less fade one will notice (as they will still be good at their worst).

Bicycle brakes are not reaching temperatures that require RBF600, you're just throwing away money in my opinion, any super-DOT4 fluid will work fine. Just for the record I've done a stint in the alps on shimano brakes and had no dramas whatsoever.

The M800 saints are in my opinion (and also ridemonkey's apparently, see their long-term review) THE most reliable brake ever made, bar none. The new saints are more finicky, but have a lot more power on tap. I'd quite confidently say that any issues with those brakes are user-related (bleed, which unlike other brands you only really need to do once, and pad/rotor choice, contamination, etc).

I am also interested in where you obtained your data regarding the boiling point of shimano mineral oil since I don't think it's something they disclose. It's just that if mineral oil really boiled, I'm sure guys like Gee Atherton would be having a bit of trouble winning world championships.

Edit - according to this post, mineral oil has a BP of 260-330°C, vs. RBF600 at 216-312°C.

[4130biker]

Anyone actually have these on their dh bike? (slx m-666) they've caught my eye, and I do like shimano...
My budget is fairly low- seems like saint is out of my price range, but a basic code r, or elixir, or slx are basically my options. 200 pounds w gear, currently running old saint m-800, but would like more all out power when needed. Any input is appreciated.

[4130biker]

Ps- Id be using 8" rotors with any of these options.
Also just realized this thread was for older slx- I'm talkin the current m-666 over here!

[Rocko]

Currently I have m675 slx, it's far the best brake I ever had on my DH bike. Previously I had elxir 9 and r. The r was better, but as good as the shimano.
M666 is almost just the same as the m675, the colors are different.
22mm pots (the overall surface is larger than in a code) plenty of power, always consistent bite point.
Short levers make them very comfortable.
I wanted to buy XT, after a few reviews I decided I don't really want to pay for the stroke adjustment.

[Magura]

Why not buy the Zee brakes?
They are intended for the purpose, and cost roughly the same.


Magura

[Rocko]

Zee was 225€, the SLX 140€. It's just roughtly the same.

Since I know what these SLXs are capable, don't see any reason to change.

[Sandwich]

I've got XTs on the way for my DH bike project. I've felt SLX 666/75 on the trail, and they were every bit as responsive as my saints, but I can't comment on DH performance or fade as of yet.

The ONLY reason I chose XT over SLX is that Nashbar had them for $106, and Jenson price matched. The end cost vs. SLX was like $16 more, but the XTs were retail packed with metal and resin pads. You have to be careful where you buy your SLXs from, as some places are selling OEM packs and only include certain pads, like metal/no-fin or resin only.

Best deals are 89$ at blueskycycling for SLXs with resin pads and fins, and Jenson has XT fronts for 99$ with metal pads and no fins. You can find other ones here or there.

There's really no difference between the two besides the bite point non-adjuster, and forged lever blades instead of cast (or something) but the metal fin pads got me.

$200 for a set of XT brakes (the best in the business right now) is pretty easy to justify compared to some used-ass and haggard codes or half a formula/hope setup. Bluesky also has zee for $150 if you feel like partying.

[ZoRo]

So where can I get front and back XTs or SLX with metal finned pads for a good deal? Jenson has a good price on XT but it's only for the fornt right??

[Sandwich]

no wheahs...

XTs come in at 129 at nashbar now (sale go byebye), and most SLXs come in at 89 with resin only. Jenson's 99 dollar setup comes without fins but with metal pads.

There are some $99 SLX sets on ebay, but I'm uncertain what pads they come with.

[amishmatt]

I wore out the original, metalic finned pads, on my XT's last summer. Replaced them with metal, non-finned pads, and can't tell a difference.

Granted, I'm not riding super long runs or anything (Mountain Creek), and I'm using Avid rotors as well, but for my use, I can't say the fins did anything.

Still love the brakes though, and I want a second set for my trail bike.

[Sandwich]

I've heard that before, and I wouldn't kick a set of non-finned pads out of bed, but for $6 more I get finned pads, olives and barbs, and a backup set of resin pads if the metal ones squeel.

PLUS, lots of people have a different interpretation of fade and such. How fat are you and what brakes did you come from? I'm fat enough where I've experienced minor fade on saint 810s, so I'm always hesitant to believe people when they say their single pot Juicies are plenty powerful for everybody.

[amishmatt]

I'm 185, was on Juicy 7's and Elixir CR Mags prior. Aside from lever feel, the XT's are better in every way.

I'm not saying the finned pads don't do anything, just that I didn't notice a difference in my application.

Never spent any real time on dual piston's, but the cost/performance ratio of the new XT's has me satisfied.