Кстати, вот наблюдения по поводу различий в ручках и суппортах у ряда современных тормозов:
From what I can see:
Deore (M6000) - standard stainless steel rotors (RT64), steel-backed resin pads (G02s)
Deore XT (M8000) - steel/alu/steel rotors (RT81, alu-backed resin pads (G02a)
Zee (M640) - standard stainless steel rotors (RT64), steel-backed resin pads (D01s)
Saint (M820) - steel/alu/steel finned rotors (RT99), alu-backed resin pads with fins (H01a)
The results appear to show much better initial deceleration with the 4-piston designs (Zee/Saint), however the cheap pads & rotors fitted to the Zee fade badly over a longer period of deceleration. There doesn't appear to be much performance difference between the Deore & the XT - around 10%, despite different piston material, better pads, and better discs.
Some piston stats:
Shimano levers (all): 10mm diameter
Older Shimano 2-piston calipers, including apparently the current lowest end models (I have some that I will dismantle at some point and check): 21mm diameter = 882π mm^2 area.
Newer Shimano 2-piston calipers: 22mm diameter = 968π mm^2 area (=+10% vs 21mm)
Shimano 4-piston: 2 * 16mm, 2 * 18mm = 1160π mm^2 (+32% vs 21mm/+20% vs 22mm)
Formula Cura 2-piston: 24mm = 1152π mm^2
Perhaps unsurprisingly the Cura 2-piston seem to offer the same power as Shimano's 4-piston design (noting as an aside that they are oval shaped albeit that the diameter quoted is the circular equivalent).
So some sort of idea what you get for your money:
1. M315 (etc) 21mm pistons, steel levers, cheaper hose - around £25
2. M365 (etc) aluminium levers - around £30
3. M445 (etc) 22mm pistons = +10% performance - around £40
4. Deore M615/M6000 stiffer hose, modulated levers, narrower braking surface (not an advantage per se, this appears to have been changed to lop 5 grams or so off the disc weight, and perhaps give a more modern looking design) - around £60
5a. SLX M675/M7000 banjo fitting, tool-less reach adjust, ceramic pistons (apparently more fragile but better for heat dispersal?) - around £90
6a. XT M785/M8000, biting point adjustment, dimpled levers on the M8000 - around £120
5b. Zee M640 - 4 ceramic pistons = 20% more performance, banjo fitting, Deore-type levers - around £175
6b. Saint/Deore XT M820/M8020 = same as Zee calipers, levers similar to M785/M8000. - around £250 for Saint or £180 for XT.
The rest of the differentiations come down to user pad/disc choice.
It's not clear why the Saint brakes are more expensive than the 4-piston XT ones, other than just market differentiation.
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Сообщение от Jahtaka
Я не могу понять твоих выводов, не имея перед глазами руки на грипсе. Ща найду тебе...
