Theoretical Question

**Jared** · 05-04-2014, 12:39 AM

Would a single, 4 piston brake caliper have just as much stopping force as two dual piston calipers?

Dave · 05-04-2014, 06:22 AM

I'm going to go with the latter. I'm thinking with a two 2 piston calipers you'd have more braking power because of the increase braking surface of the pads.

**markclark57** · 05-04-2014, 07:28 AM

Not enough information.
Stopping force is determined by a combination of applied friction points, not the number of pistons applying pressure.
One could assume that dual calipers are accompanying dual discs. This does not however lead to information about; surface areas, road contact, available traction, weight, applied force, road conditions. . .

kawboysix · 05-04-2014, 07:34 AM

Jared, two 2 piston calipers would have more stopping power than one 4 piston caliper.

Double the rotors and double the brake pad surface.

Theoretically that is.

**ringadingh** · 05-04-2014, 08:45 AM

It depends on the size of the piston and how much brake fluid is behind it. But most times two or four smaller pistons will provide better stopping power in a smaller package(caliper)

VulcanE · 05-04-2014, 08:50 AM

The biggest factors would be the diameter of the pistons surface are (brake fluid side). The more surface area, the more pressure from the same amount of force (pressure of the fluid pushing on the pistons). Also the type of friction material (what the pads are made out of), some have more "bite" than others, and some will "fade" as their temperature rises, and the other is the braking area (rotor discs), and the material their made from. But all things equal, and the only difference being the calipers, it would boil down to which has the largest surface area combined for the brake fluid to pressure against.

trosco · 05-04-2014, 11:10 AM

The concept of multi piston calipers arose to combat two problems in high performance applications. First problem was inconsistent pressure along the brake pad surface due to backing plate flex. Think of taking a 4ft long 2x4 and pushing it up against a wall with one hand at it's mid point and then use two hands each placed 1ft from each end. Which way would you get the most consistent pressure thru out the length of the 2x4? Inconsistent pressure (i.e. less that desired pressure at points along the pad to rotor contact points) reduced braking forces and in the extreme produced brake pad chatter. The other was heat transfer to the brake fluid. With a single piston caliper system you have the heat transfer focused on only the fluid that contacts the single large mass piston that contacts the pad backing plate. So the fluid in contact with the piston would boil with out first having to heat up fluid in other parts of the caliper reservoir. While in multi piston applications heat transfer is distributed amongst multiple locations and there for distributed thru more of the fluid with in the caliper reservoir. Meaning that more of the fluid has to have it's temperature raised before boiling occurs.

cactusjack · 05-04-2014, 11:39 AM

I would think that two two-piston calipers would provide more braking surface area and would be more effective and probably dissipate heat faster than a single four-piston caliper.

Silent Sam · 05-04-2014, 04:25 PM

Well more disc suface means better braking adhesion..as per related to what the brake pads have to get ahold of...but when useing the brakes a lot ..as in road raceing..hauling ass around hair-pin curves etc ..or riding the brakes down grade for long periods of time...any of them will lose a little stopping power as heat builds up !

My 02 Nomad..always has enough OEM braking power to "throw me down" if i get in a panic..or stupid !

05-04-2014, 12:39 AM	#1
Jared Join Date: Mar 2009 Location: Greeley, Colorado Posts: 6,772	Theoretical Question Would a single, 4 piston brake caliper have just as much stopping force as two dual piston calipers? __________________ Jared VBA #1051 (Former President) Login or Register to Remove Ads
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05-04-2014, 07:28 AM	#3
markclark57 Join Date: Jun 2010 Location: Phoenix, AZ Posts: 3,108	Not enough information. Stopping force is determined by a combination of applied friction points, not the number of pistons applying pressure. One could assume that dual calipers are accompanying dual discs. This does not however lead to information about; surface areas, road contact, available traction, weight, applied force, road conditions. . . __________________ 2006 Vulcan 1600 Classic "George III" (Patricia's) 2006 Vulcan 1600 Nomad "Grace" (Mark's) Mark Clark VBA #1619 TaibhseDaid@Gmail.Com "Irish" @ Maricopa County Chapter of B.A.C.A. Phoenix, AZ Last edited by markclark57; 05-04-2014 at 07:36 AM.
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05-04-2014, 07:34 AM	#4
kawboysix Advanced Member Join Date: Mar 2014 Posts: 562	Jared, two 2 piston calipers would have more stopping power than one 4 piston caliper. Double the rotors and double the brake pad surface. Theoretically that is. __________________ 2006 Nomad 1600 v&h duals, fi2000 grasshopper (kawboysix)
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05-04-2014, 08:45 AM	#5
ringadingh Join Date: Aug 2007 Location: Newmarket Ontario Canada Posts: 35,387	It depends on the size of the piston and how much brake fluid is behind it. But most times two or four smaller pistons will provide better stopping power in a smaller package(caliper) __________________ 2002 Nomad aka Bountyhunter VBA #27 VROC #18951 Login or Register to Remove Ads
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05-04-2014, 08:50 AM	#6
VulcanE Sr. Member Join Date: Jan 2008 Location: Cartersville, Georgia Posts: 4,838	The biggest factors would be the diameter of the pistons surface are (brake fluid side). The more surface area, the more pressure from the same amount of force (pressure of the fluid pushing on the pistons). Also the type of friction material (what the pads are made out of), some have more "bite" than others, and some will "fade" as their temperature rises, and the other is the braking area (rotor discs), and the material their made from. But all things equal, and the only difference being the calipers, it would boil down to which has the largest surface area combined for the brake fluid to pressure against. __________________ Cliff "VulcanE" Evans 2005 Blue & Silver 1600 Nomad VBA # 320 VROC # 20381
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05-04-2014, 06:22 AM	#2
Dave Sr. Member Join Date: Dec 2007 Location: Itchycoo Park Posts: 3,422	I'm going to go with the latter. I'm thinking with a two 2 piston calipers you'd have more braking power because of the increase braking surface of the pads.
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05-04-2014, 11:10 AM	#7
trosco Sr. Member Join Date: Feb 2008 Location: Charlotte, NC Posts: 1,464	The concept of multi piston calipers arose to combat two problems in high performance applications. First problem was inconsistent pressure along the brake pad surface due to backing plate flex. Think of taking a 4ft long 2x4 and pushing it up against a wall with one hand at it's mid point and then use two hands each placed 1ft from each end. Which way would you get the most consistent pressure thru out the length of the 2x4? Inconsistent pressure (i.e. less that desired pressure at points along the pad to rotor contact points) reduced braking forces and in the extreme produced brake pad chatter. The other was heat transfer to the brake fluid. With a single piston caliper system you have the heat transfer focused on only the fluid that contacts the single large mass piston that contacts the pad backing plate. So the fluid in contact with the piston would boil with out first having to heat up fluid in other parts of the caliper reservoir. While in multi piston applications heat transfer is distributed amongst multiple locations and there for distributed thru more of the fluid with in the caliper reservoir. Meaning that more of the fluid has to have it's temperature raised before boiling occurs. __________________ trosco: just call me Ross 2007 Black & Titanium Nomad (Nomad made 65K but got replaced 2014) 2010 Titanium Goldwing 2014 KLR 650 New Edition
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05-04-2014, 11:39 AM	#8
cactusjack Mega-Contributor Join Date: Sep 2007 Location: Where it doesn't snow...ever! Posts: 21,926	I would think that two two-piston calipers would provide more braking surface area and would be more effective and probably dissipate heat faster than a single four-piston caliper. __________________ Scott "Cactusjack" Hanks VBA #00105 H.O.G. #4250060 2011 H-D Ultra Limited 103ci :: 2011 HD Electra Glide Ultra Limited w/Stage 1 :: Rallies: Mesquite '08\|Custer '09\|Cortez '10\|Crescent City '11\|Kanab '12\|Antlers '12\|Estes Park '13\|Antlers '13\|Orofino '14\|The Dalles '17
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05-04-2014, 04:25 PM	#9
Silent Sam Sr. Member Join Date: Sep 2013 Location: On The Shakey Side Posts: 2,501	Well more disc suface means better braking adhesion..as per related to what the brake pads have to get ahold of...but when useing the brakes a lot ..as in road raceing..hauling ass around hair-pin curves etc ..or riding the brakes down grade for long periods of time...any of them will lose a little stopping power as heat builds up ! My 02 Nomad..always has enough OEM braking power to "throw me down" if i get in a panic..or stupid !
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