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Saint 820 brakes inconsistent bite point - any fixes or solutions yet?

rscecil007

Chimp
Oct 18, 2007
48
7
I know this is somewhat of a known issue (unfortunately found out after I bought my two sets).

Done plenty of reading and researching on this, but nothing definite as far as a cause or fix. Anyone heard anything?
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
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Make sure you have a good bleed. My 810s were inconsistent until I had a really good bleed on them using CHF 7.1. Then they were reliable for a year after. Just make sure to tap tap aroo the lever to get any hidden bubbles out.
 

kidwoo

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Aug 25, 2003
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Udi had a pretty good explanation here that made sense to me. It has more to do with the quad piston caliper than anything else. Makes sense because every pair of saint 4 pots I've had do that. Not a single pair of shimano 2 pots have ever done that to me.
 

rscecil007

Chimp
Oct 18, 2007
48
7
Yeah, def have a good bleed on them with all the tricks, tapping the line, push fluid up from caliper, gravity bleed it, pump fluid down from the lever, rotate lever 30 degrees up, 30 degrees down, etc.

Kidwoo, interesting all your 4 pots have done this. I've heard there are no issues with the XTR trail brakes which have the same lever, but just 2 pistons. So that would backup what you and Udi are saying. But do you or Udi know what specifically it is about the 4 pots that make them have this inconsistent bite point?

Kinda unnerving thinking you are going to lightly feather your brakes and instead you lock them up, or worst case vice versa.

Would the XTR trails work on a full blown DH bike, with 203 rotors? Obviously I think they'd be fine with 180 rotors on my trail bike.
 

boylagz

Monkey
Jul 12, 2011
485
15
SF bay area
^ I have 785 XT trail brakes and they are powerful. Ive used Avids before from Juicy 7 to Codes, and these are the best brakes Ive used so far. Ive never felt underpowered, and they modulate nice. Im loving the shorter levers vs. the Avid blades.

Get em xtr's.

Add: Brakes mounted to a V10c.
 
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0110-M-P

Monkey
Jun 1, 2009
244
2
Atlanta, GA
Even the very old shimano 4-pot XT's had this problem (and were an absolute PITA to bleed completely). You couldn't pay me enough money to buy another set of shimano 4-pot brakes again.
 

Carraig042

me 1st
Apr 5, 2011
489
85
East Tennessee
I too had similar issues with my Shimano 810's. I sold them and got Hope brakes and never looked back. Maybe you could get them warrantied and then sell the set they send you for something else?

-Brett
 

kidwoo

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Kidwoo, interesting all your 4 pots have done this. I've heard there are no issues with the XTR trail brakes which have the same lever, but just 2 pistons. So that would backup what you and Udi are saying. But do you or Udi know what specifically it is about the 4 pots that make them have this inconsistent bite point?

Kinda unnerving thinking you are going to lightly feather your brakes and instead you lock them up, or worst case vice versa.

Would the XTR trails work on a full blown DH bike, with 203 rotors? Obviously I think they'd be fine with 180 rotors on my trail bike.
If I remember correctly Udi was saying something along the lines of the pistons not being able to uniformly contract between all 4 of them. I think it's just that it's a lot easier to either get air trapped in the big caliper, or in a case where you have one piston that moves a lot more freely than even one other one, that loose one is going to move a bunch in reference to the others. I know the first gen of 4 pot saints I had took forever to settle out and start working consistently. Bleeding over and over wouldn't do it but one day, they just started working consistently. Broken in?

All I know is that where I live and with what I weigh, I don't need big fatass calipers to disperse heat. Until shimano gets that worked out, I'll be happily buying 2 pots for all my bikes. I do have that same pair of broken in calipers on my dh bike right now with some zee levers. They work great. But it took almost a full season two years ago to get them to that point.
 

daisycutter

Turbo Monkey
Apr 8, 2006
1,525
44
New York City
My Saint 810s have ben great since 2010. I have bled them once a year. I was tempted to upgrade but will now keep what i have. Thanks for putting the word out.
 

Freeridin'

Monkey
Oct 23, 2006
319
1
Colorado
The inconsistencies on the 820s do not compare to the 810s or current xt/xtr. At random, the lever will turn to a hair pin trigger, one or two pulls later it returns to normal. I've never experienced anything similar with my 810s (3 sets) or my current xts.
 
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SylentK

Turbo Monkey
Feb 25, 2004
1,262
221
coloRADo
This is interesting on the bleeding technique. Isn't shimano's method to use the funel and do gravity style? Is using Avid's syringes and technique the way to go?
 

rscecil007

Chimp
Oct 18, 2007
48
7
This is interesting on the bleeding technique. Isn't shimano's method to use the funel and do gravity style? Is using Avid's syringes and technique the way to go?
Well Shimano's method per their tec doc website is to:
-push fluid up slowly from the caliper with the syringe, and push the fluid into the funnel screwed into the lever
-gravity bleed it
-tap the caliper/line gently with a screwdriver
-pull the lever slightly and open the bleed nipple and close it very quickly a few times
-set the lever down 30 degrees and squeeze the lever a few times
-lastly repeat with the lever up 30 degrees

I believe that is all their steps, but might be slightly out of order. I always liked the Hope method though of pushing fluid down from the master cylinder, this is stupidly easy with the Shimano funnel.
 

rscecil007

Chimp
Oct 18, 2007
48
7
Kidwoo and others, thanks for the replies. Sucky to hear, but glad I'm not the only one that's experienced this. Too bad I paid a ton for two sets of brakes, but luckily Shimano is really good to deal with, so maybe I can get some XTR's Trails out of it or something. But I do worry about being 215 or so ready to ride on XTR's...

And Kidwoo what you said also makes perfect sense why the newer set of XT's (785's or whatever) on my hardtail don't exhibit this behavior...
 

Udi

RM Chief Ornithologist: “I Brake for Birds”
Mar 14, 2005
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It's not to do with the number of pistons, just the total ratio of surface area between slave and master. I tried explaining it in this post which kidwoo was probably referring to, and there have been threads in the past on the topic also.

Unfortunately I don't think there's a whole lot you can do for a permanent solution. Everyone I know with Saint brakes just deals with the excessively long throw, you can also just pump them with extra fluid on a very regular basis however they will usually just default back to their original throw after a week or two of riding.

However, if you are finding the bite point is varying (i.e. from day to day / run to run) in and out rather than just being too long / getting too long, the problem will be specific to the M820 lever. A friend of mine who runs the new XT's on his DH bike has complained about this, and given the M820 lever is very similar I wouldn't be surprised if the same things extended to it. If that is happening I would probably be looking for a warranty replacement, I'm unsure of a solution. This wasn't something that happened on the M810 and earlier levers in my experience.
 

kidwoo

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Yeah surface area is related to friction....whatever ;)


Udi said:
This wasn't something that happened on the M810 and earlier levers in my experience.
Sure as shlt did on mine. At least for a while.
 

Mo(n)arch

Turbo Monkey
Dec 27, 2010
4,283
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I am on Saints since '09 and they were absolutely flawless. One thing I notice from time to time that the bite point "goes out" on long DH runs.
Anything else is just about perfect on them.
A friend of mine had problems with his calipers. But after he warrantied the third one he is happy too.
So, no need to upgrade on my new rig?:D
 

Udi

RM Chief Ornithologist: “I Brake for Birds”
Mar 14, 2005
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Sure as shlt did on mine. At least for a while.
Now that you mention it, I remember I had the same thing happen on the XT levers that looked the same as the M810 ones. Be nice if they went back to their old (M800) days in terms of consistency and reliability.
 

rscecil007

Chimp
Oct 18, 2007
48
7
Thanks Udi, appreciate the explanation.

The throw I can deal with, but bite point does vary. One pull and it's close to the bar, ride down the trail 500 ft, and it's a hairpin trigger like someone mentioned. Barely touch the lever and the wheel is locked up like someone threw a stick in the spokes.

Shimano has been really great to work with on the issue. They said they hadn't heard anything about this, but they sent me a set of XTR levers to try out with the 820 calipers (thinking it might be a issue with the levers), but after what you posted I take it those are going to do the same thing. Ugh.
 

Nick

My name is Nick
Sep 21, 2001
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behind you, don't wait up.
it's weird, I've had the same problem you all describe with my 810 Saints, but only the rear brake. They replace 1 under warranty, and I bled constantly until I got it dialed. I always assumed it had to be the length of the brake line (Only differentiation between rear and front) or that something leaks enough to allow the tiniest bit of air into the system every once in awhile.
 

Dogboy

Turbo Monkey
Apr 12, 2004
3,136
275
Chapel Hill, NC
A friend of mine who runs the new XT's on his DH bike has complained about this, and given the M820 lever is very similar I wouldn't be surprised if the same things extended to it.
The 820 lever is actually more like the XTR lever since it doesn't have the reservoir cap like the XT. I have a set of the 820's and haven't noticed any inconsistency yet, though I admittedly don't have much time on them yet.
 

- seb

Turbo Monkey
Apr 10, 2002
2,924
1
UK
I'm curious what could cause such an issue. Does it only happen when you've been braking hard for a while, or are we talking about fairly normal conditions near the start of a ride?
 

rscecil007

Chimp
Oct 18, 2007
48
7
I'm curious what could cause such an issue. Does it only happen when you've been braking hard for a while, or are we talking about fairly normal conditions near the start of a ride?
It's done it under both conditions before.
 

kidwoo

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Now that you mention it, I remember I had the same thing happen on the XT levers that looked the same as the M810 ones.
On what calipers?

I wasn't kidding when I said that I've never had it happen with any combination of lever coupled with a two pot caliper. I thought we were onto something. Don't ruin it. :D


I've still got some of the funny lever 810 style XTs on my 4x4 Slope bike. Those things are rock solid and have been since day one. Same with another pair I had on a 7" bike for two years.

If you think about the 'reliability of their old M800 days' that WAS a two pot caliper. I'm not so sure it's the levers. What's really different about the saint ones? (810 generation I mean, not the new ones).
 
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Zark

Hey little girl, do you want some candy?
Oct 18, 2001
6,257
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Reno 911
I can't speak to the inconsistancies since mine haven't had any, but I do have a fix for brake throw. Shave down the supplied bleed block by 1mm and bleed per shimano instructions. In addition attach the bleed syringe at the end and add positive pressure and close port. This results in a really short lever throw and firm feel.
 

Freeridin'

Monkey
Oct 23, 2006
319
1
Colorado
I can't speak to the inconsistancies since mine haven't had any, but I do have a fix for brake throw. Shave down the supplied bleed block by 1mm and bleed per shimano instructions. In addition attach the bleed syringe at the end and add positive pressure and close port. This results in a really short lever throw and firm feel.
Only works for a couple of hours (~7) in my experience. I was "over bleeding" mine twice a week when the lifts were open...now I've just gotten use to it.
 

9nine9

Chimp
Apr 23, 2007
42
0
it's weird, I've had the same problem you all describe with my 810 Saints, but only the rear brake. They replace 1 under warranty, and I bled constantly until I got it dialed. I always assumed it had to be the length of the brake line (Only differentiation between rear and front) or that something leaks enough to allow the tiniest bit of air into the system every once in awhile.
On my 810s the rear caliper was leaking from between the caliper halves. I could only see it in the right light and it was a faint mist. I ended up separating the halves, replacing the O-ring and lightly facing them with 600 grit (I think) on a piece of glass. It got rid of the visible machining marks and they've been good ever since...

I couldn't warranty as I had bought them used from a kid who (I found out later) hated them cause he had to keep bleeding them...
 

rscecil007

Chimp
Oct 18, 2007
48
7
Constantly bleeding or tweaking my brakes is nothing I want to deal with. I just want to set them up, bleed them, and be done with them.

The constant tinkering would drive me nuts.
 

kidwoo

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Constantly bleeding or tweaking my brakes is nothing I want to deal with. I just want to set them up, bleed them, and be done with them.

The constant tinkering would drive me nuts.
That's why I'll only be buying XTs, or SLX from here on out.
 

Sandwich

Pig my fish!
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May 23, 2002
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It's weird, I really haven't had much of a problem with my 810s nor similar year XTs. Tinkering is not what I would use to describe working on Shimano brakes. Hopes, sure, but not shimanos. I bled my Saints twice, my XTs once (when I swapped lines). Maybe I'm not as sensitive as others, but my Saints were the best brakes I've ever tried.
 

kidwoo

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They don't all do it. And like I keep saying, I'm convinced it's the big calipers because I've never had a problem with anything but saints.
 

rscecil007

Chimp
Oct 18, 2007
48
7
They don't all do it. And like I keep saying, I'm convinced it's the big calipers because I've never had a problem with anything but saints.
Well, if mine still do it with the new XTR Trail levers, I think that probably proves your theory. If that's the case, I'm def going to be going to some 2 pistons brake.
 

demo 9

Turbo Monkey
Jan 31, 2007
5,911
45
north jersey
7 Sets of old saints and not one has done it, spent a few runs on new-r saints, and i can feel the inconsistency. I tend to think its in the lever, but I have no science to back that up
 

squiby

Chimp
Jul 26, 2010
92
13
My 810's were good when I first got them for about a season, then started being inconsistant. I bled them real good, like an hour flicking the lever and all that good stuff, then they were fine again. I then swapped to the XTR levers and at first I had the inconsistant bite point problems. I figured that I had not been as anal on the bleed so did it over OCD style, filled it from the lever down, flicking the caliper, flicking the lever then flicking and rotating everything over again. It has been great since.
 
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Zark

Hey little girl, do you want some candy?
Oct 18, 2001
6,257
7
Reno 911
Only works for a couple of hours (~7) in my experience. I was "over bleeding" mine twice a week when the lifts were open...now I've just gotten use to it.


Hasnt been my experience, lever feel has remained the same after 2 months, 3 races and many thousands of feet drop.
 

Uncle Cliffy

Turbo Monkey
Jan 28, 2008
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For what it's worth, here's a funny thing that happened to my brakes:

I've been running 810 calipers with XT trail levers for a few months now. In October I had a gnarly OTB and snapped the lever blade clean off my rear brake. Work got busy, and the bike sat until last week when I finally got a new lever.

I cut the line, put a new barb and crush tube on, re-attached, and filled up the reservoir with new fluid. (No funnel) Got rid of bubbles each time by tapping the line, to the point I couldn't put any more fluid in.

Replaced the fill screw, then rode the bike. Brake was perfect. No bleeding...

:rockout:
 

Udi

RM Chief Ornithologist: “I Brake for Birds”
Mar 14, 2005
4,842
1,037
Only works for a couple of hours (~7) in my experience. I was "over bleeding" mine twice a week when the lifts were open...now I've just gotten use to it.
That was my experience also. I felt one amazing set at Whistler, quizzed the owner out of surprise, and he said he "over bled" them weekly. There was a picture of Morganne Charre's champs bike that supports this idea, as it pressurised the reservoir fluid, and allowed a fast / dynamic way of maintaining this over bled scenario.



However this isn't technically ideal, as it changes the nature of the open system, and instead blurs the line between open and closed a little. I'm sure it worked great in practice, but it definitely shows that there is a problem with the design. I also suspect Gwin's brake failure has something to do with the problems being discussed in this thread.

They don't all do it. And like I keep saying, I'm convinced it's the big calipers because I've never had a problem with anything but saints.
RE: my previous post, it was a set of XT M775's that I had doing it (varying lever throw over run, not cool) - similar lever to M810. A friend that has the new XT M785's has been complaining about the same. I re-bled mine but still had the same issue unfortunately. I think this is a different issue to the long lever throw though, see below.

The 820 lever is actually more like the XTR lever since it doesn't have the reservoir cap like the XT. I have a set of the 820's and haven't noticed any inconsistency yet, though I admittedly don't have much time on them yet.
You're right, I see what you mean on the lever.

I think the inconsistency is a separate issue to the long-throw-on-saints issue. The varying throw possibly points to a bleed issue or an actual failure / problem in the brake that would justify a warranty claim. I'm yet to see the inconsistency on a Saint brake, but it sounds like rscecil007 has experienced just that, the description lines up with the same problem on the M775 and M785.

I wouldn't be surprised if it's just a few bad sets that have the inconsistency.

Well, if mine still do it with the new XTR Trail levers, I think that probably proves your theory. If that's the case, I'm def going to be going to some 2 pistons brake.
I wonder if it's worth just asking for a complete replacement set of M820's? Hopefully you get it sorted out anyway. Personally I think the long lever throw is just the nature of the beast, from what I've seen people either get used to it / deal with it, or switch to a different brake. However the varying throw is surely something else, and you shouldn't have to deal with that!
 

kidwoo

Celebrating No-Pants Day
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I also suspect Gwin's brake failure has something to do with the problems being discussed in this thread.
The first time I read about what happened, I think I may have even said it out loud. "hey they did that thing!" :D
 

Tomasis

Monkey
Feb 26, 2003
681
0
Scotland
I read somewhere that M810 are more consistent with proper bleed. I wonder if it retain same if I upgrade m810 with zee/slx/xt levers? if some blame it for larger surface size, lever are less relevant?.
 
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