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Old Feb 7, 2017 | 02:45 PM
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Default Brake master cylinder

If the stock master cylinder on my bike is a 9/16 bore, could I get away with using an 11/16 bore one, or do I have to stick with a 9/16 bore. This is for the front brake.
 
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Old Feb 7, 2017 | 03:27 PM
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Stick with the stock size. The larger one is for dual front brakes
 
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Old Feb 7, 2017 | 04:51 PM
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If you go with the 11/16" bore you will not have any feel to your brakes, they will be like a light switch, you move the lever a c*** hair and they will be on.....hard. I tried this one day on my bike for grins, needless to say it came right back off for a 9/16" bore.
 
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Old Feb 7, 2017 | 06:38 PM
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Hahaha ok. I wasn't thinking that it would move too much fluid and I'd end up going *** over tea kettle if I used the front brakes. Looks like I'll be sticking with the 9/16 bore. The only reason I was asking was because I'm swapping to a hydraulic clutch, and Harley sells a kit with the chrome brake and clutch reservoirs/master cyl, but it's 11/16 bore. Thanks for the clarification. I appreciate it.
 
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Old Feb 7, 2017 | 07:15 PM
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That kit must be for a Touring Bike?
 
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Old Feb 7, 2017 | 08:40 PM
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Originally Posted by multihdrdr
That kit must be for a Touring Bike?
"Fits ’02-’05 VRSC models. Also fits hydraulic clutch equipped ’96-’05 DynaŽ and SoftailŽ and ’96-’04 Touring models with dual disc front brakes." Is what it says it's for. Obviously mine doesn't have a hydro clutch yet. And on the Harley site it says it fits heritage softails and other softails that I know don't have dual disk brakes. That's why I wasn't sure.
 
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Old Feb 8, 2017 | 10:04 AM
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Originally Posted by HDnoob
"Fits ’02-’05 VRSC models. Also fits hydraulic clutch equipped ’96-’05 DynaŽ and SoftailŽ and ’96-’04 Touring models with dual disc front brakes." Is what it says it's for. Obviously mine doesn't have a hydro clutch yet. And on the Harley site it says it fits heritage softails and other softails that I know don't have dual disk brakes. That's why I wasn't sure.
The statement of fitment for single disk models probably refers to the hydraulic clutch portion of the kit which would in fact fit those bikes. Probably just a slip on Harley's part to clarify about the master cylinder portion of the kit on their site. I would have to imagine that the instructions for the system probably mentions these specifics. It's not uncommon to find discrepancies like this among all the different products with so many varied applications.
 
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Old Feb 8, 2017 | 10:30 AM
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It's really not a slip...

"Fits ’02-’05 VRSC models. Also fits hydraulic clutch equipped ’96-’05 DynaŽ and SoftailŽ and ’96-’04 Touring models with dual disc front"


Pretty Clear and accurate...although dual disc Softails are very uncommon, they were produced and I'm pretty sure there would have been a hyd clutch kit offered through "Parts"

Such as the 2003-04 CVO Deuce (Dual Disc)


Your application either fits the "Fitment" statement or it doesn't

.
 

Last edited by multihdrdr; Feb 8, 2017 at 10:32 AM.
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Old Feb 10, 2017 | 11:45 AM
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I upgraded my front brake to a Performance Machine 6 piston caliper ,for my 07 Night train. PM does recommend using the bigger bore. Other than that your 9/16 is fine.
 
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Old Dec 17, 2017 | 04:12 AM
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Originally Posted by dfwhockey17
If you go with the 11/16" bore you will not have any feel to your brakes, they will be like a light switch, you move the lever a c*** hair and they will be on.....hard. I tried this one day on my bike for grins, needless to say it came right back off for a 9/16" bore.
Well, they'll come on quicker as the larger master cylinder will move more fluid, but the pressure will be lower. So it will feel harder, but you'll actually have less braking force available.
 
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