Converted to 9/16 master cylinder

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Zach

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5,785
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Portland, OR
When I put my 21 on 5 years ago I converted to a single rotor. I left the stock 11/16 master cylinder on and put a 6 piston caliper on. It worked ok, but the lever was always real firm. I've had a 9/16 master cylinder on my work bench for 3 years and finally decided to convert. I used a 7/16 banjo bolt on top and a 3/8 banjo bolt at the caliper. This is how the parts manual showed for a softail. It made a ge difference.

I've got a 13" rotor on order from Nautical along with a bracket to use my current Jay-6 caliper. Should make it work even better.

Zach
 

Zach

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Portland, OR
I want to do the same but I can't find one with the new style brake lever.

You might check with a dealer parts book, but I think when HD switched to Brembo brakes the master cylinder changed and is the same bore diameter for both single and dual disks. Not sure which year that happened.

Zach
 

Wanna Ride

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If I remember correctly (I think it was David at WanaRyd was the most recent one to tell me), the '08 and up, master cylinder is the correct one, and doesn't need to be changed.
 

WanaRyd Wheels

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You are correct you can retain your current master cylinder on an 08' Up it will work properly, however it isn't exactly the same master cylinder, it is a 10/16.
We have never had any customer complaints with running their stock master cylinder; this is one instance where Harley did the aftermarket folks a favor.

If I remember correctly (I think it was David at WanaRyd was the most recent one to tell me), the '08 and up, master cylinder is the correct one, and doesn't need to be changed.
 

SUAVE

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Carlsbad NM
I got a 2010 roadglide (no ABS) and i installed a HHI 6 piston with my stock master and its real firm and takes more pull to get to stop. is this cause of the no ABS?
 

Zach

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Portland, OR
I got a 2010 roadglide (no ABS) and i installed a HHI 6 piston with my stock master and its real firm and takes more pull to get to stop. is this cause of the no ABS?

Is your rotor brand new? If so, it might take some time to bed in the pads to the new rotor. I'm also assuming the system has been bled correctly. Last thing that comes to mind is the banjo fitting on the caliper. If it's to small I would think a stiff lever would be apparent.

Zach
 

RLJ676

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St Clair Shores, MI
Is there any way to run a single w/ stock Brembo caliper? I'd assume a kit w/ a bigger disc would still have some decent stopping power or do you have to go 6 piston?
 

Bill

I used to own some shit!
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Is there any way to run a single w/ stock Brembo caliper? I'd assume a kit w/ a bigger disc would still have some decent stopping power or do you have to go 6 piston?

I had a single 11.5" disk and wouldn't recommend it. Lots of people do it but it wasn't for me.

That being said the Brembo disk is 11.8", that's a marginal increase in stopping power IMO.

If you are stuck on a single disk get a 13" rotor "or bigger" and a 6 piston caliper.

Just my opinion of course.

Sent from my ADR6400L using Tapatalk 2
 

crutter

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Frederick, Md
Rj you need to step up to a 13" rotor with a 6 piston caliper to go single sided. Running one brembo caliper(4 piston) will give you a rock hard lever that is super inefficient. If it did work u may over heat the front brake causing glazed over pads or ruin your rotor.
 

RLJ676

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587
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St Clair Shores, MI
I had a single 11.5" disk and wouldn't recommend it. Lots of people do it but it wasn't for me.

That being said the Brembo disk is 11.8", that's a marginal increase in stopping power IMO.

If you are stuck on a single disk get a 13" rotor "or bigger" and a 6 piston caliper.

Just my opinion of course.

Sent from my ADR6400L using Tapatalk 2

Rj you need to step up to a 13" rotor with a 6 piston caliper to go single sided. Running one brembo caliper(4 piston) will give you a rock hard lever that is super inefficient. If it did work u may over heat the front brake causing glazed over pads or ruin your rotor.

Right, there's always the "right" way haha, just seeing if there's a cheaper way that works. Thinking the much larger diameter increases the torque on the wheel from the same brake input.

Crutter, they're saying the 10/16 Brembo master can run a single, just like on a Dyna etc so I would think it could work, just maybe not stop well enough? The smaller bikes don't have 6 piston singles do they?
 

Zach

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5,785
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Portland, OR
No. HD doesn't make a 6 piston. You can't just bolt on a 13" rotor and run the Brembo either. The caliper won't fit. You need one of these to run your Brembo,

http://www.jpcycles.com/product/242-832

or make sure you get a 6 piston caliper that is designed to work with the 13" rotor. The mounting angle is different.

I got my stuff from Nautical. Great deal and service.

Zach
 

RLJ676

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587
Location
St Clair Shores, MI
No. HD doesn't make a 6 piston. You can't just bolt on a 13" rotor and run the Brembo either. The caliper won't fit. You need one of these to run your Brembo,

http://www.jpcycles.com/product/242-832

or make sure you get a 6 piston caliper that is designed to work with the 13" rotor. The mounting angle is different.

I got my stuff from Nautical. Great deal and service.

Zach

Thanks for the link, I knew it would take an adapter to fit it didn't know if the adapter existed. So you can run a single sided 13" setup without a 6 piston, it's just less effective. Might be a good stepping stone though to spread out the costs.
 

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