Sunday, May 14, 2006

Shimano Saint Disc Brakes

The Shimano “SAINT” groupset is Sh!tmano’s no compromise, strength and stiffness over weight groupset, aimed at heavy freeriders and DH racers. The cranks can be seen on both my bikes, and just about any body who is serious about going large, the hubs are pretty good too, as is the front and rear mechs + stubbie levered shifters…. but all that stuff is for propelling you forward… what about when you need to stop? (picture from RideSaint.com)

THE STORY OF THE STOPPAGE, AND THE NOT SO....
I’ve had numerous brake systems on the Chameleon, starting with Hope Minis (old style) and the Mono M4 system. I bought the M4’s for two reasons: More power and looks - they do just look so damned good, don’t they ?

About a year ago, when I decided to give this DH lark a go, I built myself up an Orange Patriot for messing on. I wanted to avoid M4’s again, as I’d had no end of trouble with them on the Chameleon (I’d upgraded the hoses, replaced seals, replaced Pistons, replaced bore caps, and the damn things still wouldn’t work reliably), I didn’t particularly like the feel of Hayes (on/off) and Magura Gustavs are just plain weird, with all that floating calliper business (Work very well though). These also came in slightly cheaper than all of the above too, so I thought I was on to a winner.

REVIEW OF THE STOPPAGE
I rode a full season (numerous races and lots of practise/mess about days) on these anchors, and for the first time, I could just get on with worrying what I was riding over, not about whether my brakes will work or not. Riding that bike was a pure joy (helped no doubt by it’s rear end!). Their sleek 2-pot mono bodied calliper hides an amazing amount of power and control. I got on with them so well, I binned the Hopes on the Chameleon and stuck some of these on, and I’ve not looked back.

While they don’t have quite the modulation of an M4 (there’s only so much you can do with only 2 pistons!), the power (and I know I’m opening a can of whoop ass with this) shames the Hopes. In all fairness, they shame the Mono 6Ti too.

CONTROL OF THE STOPPAGE
Controlling the power is a little bit of a handful to start with, (my dad jumped on my bike to ride it up the drive and almost came off after grabbing a fistful, which was highly giggleworth!) But you soon learn where the feather point is, and I was following a guy down Mortimer Forest today where his back wheel was locking but mine just kept rolling. (Yup-means you actually have more traction and don’t create braking bumps fellas)

I now have complete confidence to ride with the brakes off (anyone riding behind me will testify!) knowing when I need the stoppage, it’s there in great big crate loads.

RELIABILITY OF THE STOPPAGE
I’ve still not had to touch the Saints on my DH bike (now the wonderful Gemini), and have only changed the pads due to contamination!

OK, SO NOW YOU WANT TO FIT THEM TO YOUR BIKE, RIGHT?
Tis worth noting that Shimano don’t do pre-assembled systems like Hope and just about everybody else.

Sold as: Calliper + Disc + 2 sets of pads (yes, that’s 2!) + levers + hose and oil.

Ok it’s a pain, but it does mean this: you have ultimate choice over what lever you want (Cheap as Deore, as good as the specific Saint Levers, or even floppy shi(f)t, if you’re that perverted). It does mean that you can get the correct length hose, and get it routed through your frame if you have a Orange or something that routes the hose through the swing arm.
The Standard hose is also excellent, better than other hoses on other systems, but Goodridge is so tarty ;)

Fitting the calliper is an absolute doddle thanks to the one post mount style calliper with adaptor affair, eliminating the need to get your mounts faced if your fork is I.S. and allows for a bit of scope if you’ve bent your rotors like me :D

Only downside with these brakes is the limited Rotor sizing; they only come in 203mm mega-stoppage size or 160mm “My rotor is smaller than yours” size. However, if you can source a suitable 180mm rotor, you can buy a rear 160mm calliper+mount set and run it as a front 180mm as long as you have I.S. Mounts. (I.S. mounts are 10mm closer to the dropout on the rear than they are on the front!) Shimano and Hope make adaptors to allow you to fit a 20mm bigger disc to your I.S. setup, so you can run a 180 rear like me. They also currently only offer the supplied rotors in Oversized Centerlock fitting, which means you can only sling em on Saint hubs, or various other “freeride/DH” hubs made by companies such as DT Swiss and Sun Ringle. I think Mavic also do hubs to suit too. Ok so the rotor situation sucks, but Sh!mano are reported to be offering more options for 2007 so sit tight!

TO SUM UP THE STOPPAGE:

  • Saints are THE best brakes I’ve used.
  • Hayes are great, but are a little to on/off for me, and the cheaper HFX’s have a habit of breaking.
  • Hopes just dick around with you (ducks salvos from Farqui and Rob – sorry guys)
  • Avid are great, but have a habit of breaking, full stop.

13 Comments:


Farqui said...

An interesting review there DDave - from our man on the "inside" of the industry ;)

Hopes are without a doubt THE most pimptastic stoppers. Athough Avids updates for '07 look nice. What's the scoop with Avids reliability ?

Hope's are for ideal for tinker-ers but some fit and forget stoppers would be nice. Sh!mano restricted rotor sizes are a pain, esp. as 180mm is the most common.

I find the adaptors most manufacturer's use look so clumsy, but Avid's take on it with their easy alignment system looks slick.

Chipmunk is satisfied her XT's, the slender brethren of the Saints but I just can't get excited about Sh!mano kit. Perhaps I'll have to try your Saints sometime...


daahnhilla said...

Thanks. Agree with almost everything there, the Avid alignment system is really great and a doddle to set up.
I find the Shimano adaptors don't look too bad, the cool writing makes it look nice and important!
They are definatly the most under rated brake out there.

I think it's something to do with the anti Microsoft[shimano] mentality going around still, but I'm seeing more and more of
these anchors on bikes each time I go out.

Looks wise the caliper does look quite mean and like a smaller version of the M4 with that pointy bit sticking out the back.
Also looks quite sutble, if you like that kind of thing. I also find the hose fittings on Hopes clumsy looking.

Only thing I don't agree with is the part about hopes being ideal for tinker-ers - I'm a serious tinker-er and I just found it frustrating constantly
having to fettle to get them to work, I like fettling to make things different or better!;)

Avids have had issues with levers binding although they seem to have sorted that. They aren't as bad as Hopes (ouch), but not reliable enough for me.

One last point...

Hope need 6 ti pistons with big vent holes and a 2-piece rotor and braided hoses to make a brake that doesn't cook on Alpine descents....
I've never heard of ANY shimano, hayes or Avids cooking with their 2piston "normal" rotor jobbies.....


;)


Farqui said...

In an effort to combat heat buildup, haven't Hope changed to phenolic (or sumat) pistons ?


Dan Howell said...

Cool write-up and puts across a very important point and one I've always tried to impress upon people... if most family saloons weighing up to a tonne can retard themselves perfectly fine with a single sliding piston caliper, or dual piston calipers at the most, then why the F would you need 4 or 6-potters on a bloody mountain bike, FFS?

It's all bling and marketing. In terms of stoppage they should all be perfectly capable of stopping Average Joe - if they're not, they're sh1te :). In terms of feel, modulation, looks, etc then fair enough - pick something that suits you - but in terms of outright stoppage any brake manufacturer worth his salt should be able to make something fully functional for 90% of users without the need for a small mortgage...


Farqui said...

"It's all bling"

Oh yeah, bring it on :p

Hey Brumster, if 2-pot sliding piston calipers are fine then why are you part way thru fitting great hulkin' 4-pot, fixies to your Pug ? ;) Not that I'm against big brakes you understand but sir is :huh me...

Q: When will ABS be fitted to MTB's ?!


Rob said...

Most interesting comments guys, here's my opinions....

I've tried XT (05 on) and I think they're grrreat, a little on/ off but plenty power. LX is a little softer.

Hope M4 (mine) are very useable, nice feel and I think good power but they have substantial problems.

1. They have only 10thou total disk clearance and it's not adjustable. You try getting a disk to run that straight, it can be done but not easily.

2. The centre rest point moves in use, my rear recently moved over 20thou whilst pad wear was only 3 thou assymteric and the OTHER way! The brake remained firmly on and I could do nothing about it as I had no shims.

3. The Shims supplied with the brake are 11thou, and up, shimming them is therefore very difficult give the disk clearance is only 10thou.

4. They are open so a thinner disk will not increase clearance.

5. The pads are extremely susceptible to contamination, a whiff of GT85 and they've had it.

If you're fitting disks, and you want a good reliable practical system, use Avid BB7 cable. Absolutely bomb proof and if you get gunge in em you can widen the pad clearance while you ride.

They're also among the cheapest out there and work well with a V brake lever. Get em, fit em, forget em.

Will contact Hope with my moans and let you know.


Rob said...

HOPE SAYS......

I had a long chat with the folks at Hope and here's what they advise.

Most problems are caused by sticking or slow pistons. This is the cause of the drifting centre point and reshimming to compensate is the wrong solution.

Hope remove the pistons clean and degrease them, same with the pots and seals. They use Hunter Silicon Lubricant applied to the seals. The pistons should slide in vitually friction free.

I raised the point of pad contamination, they recommended Isopropyl Alcohol to clean them. Similarly the disks but they know of no mechanism that can result in a disk being permanently contaminated.

They did say that there is a mechanism caused by sticking pistons that will result in the disk being bent over when applied and full pad contact is not achieved. This is the result of constantly reshimming the caliper to follow the sticking piston,

Copperslip will contaminate Hope pads.

They recommend Dot5.1 brake fluid.

2007 brakes will be mounted on a sliding post for easy fitting.

2007 Levers will have Avid style pad clearance adjust, it is thought these will be compatible with Mono M4 and Mini's.

So I'll try to source some Silicon Lubricant and let you know how I get on.


Rob said...

Oh and they also said they're happy to take a look at any customer brake that is misbehaving. Farqui get that back brake off and post it.....


Farqui said...

No need, the pads were contaminated and once replaced work a treat. Oh, and a thorough bleed with the Hope kit defo helped.

I now regularly douse the disc with Isoproyl.

Good to hear that the manufacturer are willing to help out it's customers tho, well done.

I'm interested to see how silicone on the pistons improves yours, keep us posted. I've dribbled brake fluid on 'em (externally) but it didn't help so a full dismantle would be my next logical step. I've a complete rebuild kit on standby...

So they're introducing a pad adjustment for '07, just like my trusty ol'C2s ;)


Rob said...

Update...

So I stripped my rear M4, and they were right, the inner large piston wasn't moving. I took it out degreased it applied lube as recommended and replaced it. Moved like a dream it did, very free. The other 3 were fine.

I bled the brake and put in new sintered Hope pads.

So did the centre point move back? Did it hell, it's just the same as before except all the pistions now move.

The brake feels better though I haven't bedded it in yet but it did feel the same as when I first fitted it.

I'll keep you posted.


Farqui said...

So let me get this straight, after a strip and clean they still don't sit centrally ?

Good to hear that they're back to feelin' strong again. I hadn't realised yours had gone off the boil already.


Rob said...

Nope they don't centralise after cleaning and greasing it was much the same.

New theory...

I studied the exploded diagram of the mini lever for a while and realised the diaphragm in the reservoir is the expansion chamber, ie compressible air one side and fluid the other. I took my badly behaved rear brake cap off and found there was fluid both sides of the diaphragm. I cleaned it and removed a small amout of fluid, I just dipped a small piece of tissue in the fluid.

The result was much greater pad clearance, up to 16thou from less than 10. There was no loss of performance either and the gap remained after a 5 mile scoot in the countryside.

I think my bike rolled properly for the first time ever!!

I note with interest that the rear brake with new pads now has greater clearance than the never touched front.


Farqui said...

Excellent news. I'll have a quick check of my master cylinders when I'm back from hols.

Although, I suspect that I ought to go the whole hog and install the full rebuid kits at some point...


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