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Frankenbrakes and brake improvement discussion

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Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
A friend is returning a set of Formula C1s I lent him after both levers failed. The calipers and hoses are okay though. Could teh monkeys suggest me a good set of levers to match them to? Or would it be just a waste of time?
C1 = 2x 22mm slaves and DOT fluid, so you should have plenty of options.
Depends how much you want to spend or what's available, but any of the Formula DOT levers would be a safe bet + direct fit, Hope Tech3 levers would work fine if you sort out the right lever fittings. Older Avid/SRAM may be OK, you'll get higher peak force but potentially with throw too long, still viable / worth trying though.

I wouldn't bother spending much, but if you have something lying around / available cheap then go for it.
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,858
7,106
borcester rhymes
hey @Udi ,
Speaking of lever options, what might a good lever be for the MT5s? I've got the bite I want with metal pads, but I think I'd like to avoid servo wave levers if possible. I have XT and Tektro brakes hanging around that are also mineral oil if that helps, but I'd be open to scoring a set of adjustable, robust levers that should be compatible.
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
@Sandwich
If you can make an exception for a servo-wave lever I'd try them with the M615 deore levers if you can find em new, probably available still. From memory troy was running them with MT5 or MT7 and found that they were possibly a bit better constructed internally than the "higher end" Shimano levers. I'd shoot troy a PM and see what he recommends. I'd say jury's still out on the newer M6000 deore lever but either way I think the end result might be decent, and worst case, a pretty cheap mistake to make.

RE: Tektro lever, hard to guess without knowing which model and ideally the MC size, but could try it and see.
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
My plan is to cut the hose, leaving a length out of the MC, jam that in a vice and unscrew it. think it'll work?
I think if you're gentle you can probably undo it without breaking it still. You could also very gently clamp the nut in vice and rotate lever around it. Try it your way first, either way if you work slowly and carefully I doubt you'd have any problems getting it out.
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
2,074
1,442
SWE
I went for Shimano MT500 levers with my Magura calipers and sometimes miss the tool free reach adjust...
 

HAB

Chelsea from Seattle
Apr 28, 2007
11,592
2,028
Seattle
fuck lads a compression nut on one of my levers has a crack in it. It'll crumble away for sure if I go at it with a spanner. Anyone ever encounter this?

My plan is to cut the hose, leaving a length out of the MC, jam that in a vice and unscrew it. think it'll work?
If you cut the hose you could get a 6 point box wrench over it and hold it pretty fully captive. That'll be loads better than using an open end.
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
2,074
1,442
SWE
Have you had any inconsistencies with the MT500?
I had at the beginning (inconsistent bit point) which might be due to a poor bleeding by myself since they have been ok after a second bleeding during which I swapped the Magura fluid for Bionol. I also noticed last week that after having the bike upside down the lever went to the bar for the first few strokes.

Looks very similar. Mine have just Shimano written on them

Also do you have slave piston diams for the new Hayes you mentioned?
4 times 17mm
A bit sad they went for equally sized pistons...
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
4 times 17mm
A bit sad they went for equally sized pistons...
Probably not as big a deal as TS makes out.
Do you think they reduced the rollback over past calipers, from your graph comment? Good to have more caliper options anyway, especially from Hayes, as they usually become available quite cheap.

Let us know if the bite point inconsistency comes back on your Shimano/Magura or stays good. I'm curious about that - partly because we have a camp of people who insist this isn't caused by levers, partly because the M6000s (assuming the same) are so cheap that if they are consistent/reliable they'd be nice to recommend.

i think that fcs yoke was doing sweet fuck all. Are they actually worth using?
"Free stroke" adjusters are plain dumb because all they do is increase the physical distance the MC piston must travel before it even reaches the timing port (i.e. they can be thought of as "stroke increasers", that's all they are capable of). It's 100% dead weight. This is true for Hope, SRAM, Formula. Shimano's does almost nothing, possibly for the best.

On Formula, I find no FCS = better. They can seize on and be very hard to remove from the MC body too so don't beat yourself up over it. You just saved a few grams and improved your brake, enjoy.
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
2,074
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Do you think they reduced the rollback over past calipers, from your graph comment?
As I understood it they put some efforts into the levers to make sure the seal lip of the MC is very close to the timing port as well as probably making the timing port smaller.
p3pb16077153.jpg

What they did with the rollback is unclear from what I read... but seal material and rollback have been taken into consideration according to pinkbike FWIW

They went for 8% stiffer hose than before too. I have no idea what it's worth against the other brands.
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,858
7,106
borcester rhymes
@Sandwich
If you can make an exception for a servo-wave lever I'd try them with the M615 deore levers if you can find em new, probably available still. From memory troy was running them with MT5 or MT7 and found that they were possibly a bit better constructed internally than the "higher end" Shimano levers. I'd shoot troy a PM and see what he recommends. I'd say jury's still out on the newer M6000 deore lever but either way I think the end result might be decent, and worst case, a pretty cheap mistake to make.

RE: Tektro lever, hard to guess without knowing which model and ideally the MC size, but could try it and see.
I have tektro aurigas on the hard tail. They aren't bad brakes for a pure entry level brake. New pads and clean rotors and they're ok. They are also mineral oil and comfortable enough. What can I measure to give you an idea of compatibility?

There are also Chinese knockoffs on Amazon I'm tempted to try, just because they are purple
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
I have tektro aurigas on the hard tail. They aren't bad brakes for a pure entry level brake. New pads and clean rotors and they're ok. They are also mineral oil and comfortable enough. What can I measure to give you an idea of compatibility? There are also Chinese knockoffs on Amazon I'm tempted to try, just because they are purple
Would need to know the MC piston / bore diameter, probably hard to find without pulling one apart but worth some google-fu just in case. The mechanical lever measurements are easy after that, but need both to give conclusive answer without testing.

If the hose fitting threads match the Magura you could just try and see without using up any parts. I find most brakes work great on hardtails and even trailbikes, can be a different story under constant abuse. I'm all for trying stuff though, am running a few nice quality knockoff parts myself.
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
As I understood it they put some efforts into the levers to make sure the seal lip of the MC is very close to the timing port as well as probably making the timing port smaller.
I just read the article, I think it's cool that they at least considered a lot of things that no one other than trickstuff really has. They've got a glide ring on the MC piston, and it sounds like the timing adjustment can be changed internally (?) and potentially allows positive adjustment unlike any other "throw adjust" BS on the market. I wonder if the range can only account for mfg variations, or actually compensate for wear over a few years. The wear that causes the timing to change in any brake is usually at the topout plate mechanism. Usually a ball end wears a conical groove in the topout plate (inside edge), or the plate itself starts wearing into the circlip, or something similar. Theoretically replacing those parts should reset the timing on any brake where parts are available.

I did notice one thing that sucks on that lever design though - the reservoir sits below the MC bore, thus any air in the system will accumulate in the MC, instead of rising up into the reservoir and out of the hydraulic system. At least that's what the orientation in the image suggests.

Anyway, 4x 17mm, could be good for mixing with Hope/Formula. Do you know what the Stroker Ace had?
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
2,074
1,442
SWE
I did notice one thing that sucks on that lever design though - the reservoir sits below the MC bore
I mentioned that earlier in this thread. It is indeed not optimal but if Hayes managed to get the rest right (short lever throw, good power, consistency, reliability and ergonomy) I could see myself living with such a flaw. Time will tell!

Do you know what the Stroker Ace had?
No

By the way, do you know the purpose of the second port on the lever? The only thing I can think of is that it would probably help bleeding the lever faster, specially the area between the 2 seals of the MC.
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
By the way, do you know the purpose of the second port on the lever? The only thing I can think of is that it would probably help bleeding the lever faster, specially the area between the 2 seals of the MC.
If you mean the identical/symmetrical one on the underside (?), it's just because the lever is ambidextrous (so you can have a bleed port accessible from the top whichever way you run the levers). Same as SRAM/Formula have done in past.
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
2,074
1,442
SWE
If you mean the identical/symmetrical one on the underside (?), it's just because the lever is ambidextrous (so you can have a bleed port accessible from the top whichever way you run the levers). Same as SRAM/Formula have done in past.
I meant the port labelled C on the picture below. B being the timing port.
hayes-dominion-hydraulic-disc-brake-master-cylinder-cutaway2-1068x712.jpg
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
I meant the port labelled C on the picture below.
That port (or equivalent) is present in any open-system brake.
I think the best way to understand is to imagine what would happen if that port didn't exist:
  • The secondary seal and cavity must exist to begin with, because obviously otherwise the reservoir would leak and lose fluid to the atmosphere once the timing port was crossed by the primary seal. So that secondary cavity is essentially just a closed-volume, sealed space which eliminates the need for a complicated linear seal to keep the reservoir closed after the timing port is crossed.
  • Without the secondary port, there would be no way to initially lubricate / fill the back side + cavity of the primary seal easily. You'd have to get fluid in and air out through the single primary timing port, while having a syringe attached at the reservoir, and holding the lever depressed. The amplitude of this problem is increased greatly by the requirement for the timing port to be as small as possible. This would be annoying even with the nice vacuum-able bleed system (SRAM/Formula/Trickstuff/Hayes) but an incredibly difficult task on Shimano / Hope tradtional style bleeders.
Open to correction, but I know for sure it's nothing new / different.
You can see the same port here on the DRT lever:
drt_timing.jpg


There are other ways to achieve the same function as that cavity and port, eg. Formula (and others) have an arrangement where the primary seal is fixed and the timing port is actually a series of radial ports in the piston which use the inside of the hollow piston to transfer and store fluid, before/after acrossing the stationary primary seal (black part visible to the right of spring and white guide) respectively:
form_timing.jpg

In this case there is greater timing port (thus bleed flow) area, and the chamber to the left is in the (vacuumable) bleed path even while the brake lever is static. Very different implementation but same function and both systems (can) work well.
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
2,074
1,442
SWE
You are right, my memory is failing me... I was sure I just saw only one port on the Guides R I replaced the MC on a month ago but after checking the web, l just found picture with 2 ports. Maybe I need glasses! ;)
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,918
1,213
I am having second thoughts about the new Hayes brakes, specially about the fact that the reservoir is below the master cylinder... intuitively I would say that any eventual air bubble will have quite some difficulties to escape the MC to the reservoir. Don't you think?
Sorry I missed it the first time, I think this is important enough that I wouldn't personally run that lever - I find any brake will end up with some air in it at some point (since perfect bleeds are almost impossible and fluid has varying amounts of dissolved air - some of which can separate and rise with time and use). When that happens I think it's important that the air can easily escape the active hydraulic system, as you suggest.

That's not to say the brake isn't worth a shot, but if budget allows I think the Cura4 might be a better option. I could see myself using the new Hayes calipers in a franken mix though.
I found UDI's next brakeset.
Looks legit.
I like the ZOOM brand but I'm holding out for the new brake from RISK.
 

Bike078

Monkey
Jan 11, 2018
599
440
I like the ZOOM brand but I'm holding out for the new brake from RISK.
ZOOM also makes forks Udi. Hold out for those too. Add a few more pesos to the price of the Zoom brakes and you can get Shimano's entry level hydro brakes.
 

DavidG

Chimp
Apr 19, 2014
2
0
Does anyone know anything about mixing Magura MT5 and MT7 levers and calipers? The caliper seems identical from the outside but the price is very different. What would be more beneficial, switching a MT5 caliper or lever for a MT7 equivalent?
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,858
7,106
borcester rhymes
Mt5 levers have better ergonomics from the start, the manual bolt offers closer reach than the knob in the mt7. All of the fancy lever blades are not compatible with the mt5 lever body however.

The calipers are identical, but the mt7 uses four pads while the mt5 uses 2. The four pads offer more bite and more variety of compounds. To swap, you can simply order a new set from magura, but all of the aftermarket sets require bolts that aren't included.

My suggestion, buy the mt5s, ride them as is for a trail brake, swap out the pads ASAP for a dh brake. Buy the mt7 for a more complete brake from the start
 

chris_f

Monkey
Jun 20, 2007
390
409
Also, you can't fit the HC3 lever on the MT5, but I've yet to figure out why. It really fixes a lot of the weird ergonomics the MT7 has with standard levers.

I've run normal and HC3 on my MT7s back to back and no contest I'd take the HC3 any day even if it means I get slightly less leverage and therefore slightly less absolute power.
 

chris_f

Monkey
Jun 20, 2007
390
409
That's my backup plan for when I inevitably wreck these flimsy plastic master cylinders at least.
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,858
7,106
borcester rhymes
That's my backup plan for when I inevitably wreck these flimsy plastic master cylinders at least.
yeah, I keep my eyes peeled for shimano levers or alternatives. I've honestly been eyeing those chinese tektro knockoffs as replacement levers. As it stands, I might just move the maguras onto my trail bike then I'll want to keep the lightweight levers
 

marshalolson

Turbo Monkey
May 25, 2006
1,774
532
@Udi @HAB

sorry for the ping, just looking for a little help on the ROR brakes.

Very much digging them overall, but the inside front piston only moves freely whe. The outside piston is pinned down. I have tried all the usual tricks of cleaning in/lubing it, but no success.

Any suggestions beyond replacing the seal?

Thank you!
 
Last edited:

djjohnr

Turbo Monkey
Apr 21, 2002
3,115
1,801
Northern California
Mt5 levers have better ergonomics from the start, the manual bolt offers closer reach than the knob in the mt7. All of the fancy lever blades are not compatible with the mt5 lever body however.

The calipers are identical, but the mt7 uses four pads while the mt5 uses 2. The four pads offer more bite and more variety of compounds. To swap, you can simply order a new set from magura, but all of the aftermarket sets require bolts that aren't included.

My suggestion, buy the mt5s, ride them as is for a trail brake, swap out the pads ASAP for a dh brake. Buy the mt7 for a more complete brake from the start
They do make a HC lever for the MT5 - http://www.magurausa-shop.com/product.htm?pid=218692&cat=11915
 

HAB

Chelsea from Seattle
Apr 28, 2007
11,592
2,028
Seattle
@Udi @HAB

sorry for the ping, just looking for a little help on the ROR brakes.

Very much digging them overall, but the inside front piston only moves freely whe. The outside piston is pinned down. I have tried all the usual tricks of cleaning in/lubing it, but no success.

Any suggestions beyond replacing the seal?

Thank you!
I haven't really had that issue with either of my pairs, but I'd be inclined to just do new seals and pistons. The kit is only about $20.