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Makes And Models => Zero Motorcycles Forum | 2013+ => Topic started by: rayivers on August 23, 2015, 06:38:31 AM

Title: Front brake master cylinder upgrade
Post by: rayivers on August 23, 2015, 06:38:31 AM
It was great to get my front brake quiet, but it was still weak.  Not anymore. :)

After comparing the relative piston size of the Zero FX and Yamaha YZ master cylinders, I just had to try a YZ one out.  I picked up a decent 2012 on eBay for $50 shipped (it's almost $300 from Yamaha), and put it on yesterday.

Installation was a pain, but I finally got all the air out.  The lever feel is exactly the same as my YZ (softer than the rock-hard Zero MC). The braking performance is greater though, as the Zero rotor and Honda brake pads I'm using both have more surface area than the Yamaha units, and the Zero Nissin caliper has bigger pistons than the YZ as well.

Here it is on the bike - it's used on pretty much every Yamaha YZ dirt bike from 2008 to 2016 (p/n 5XC-W2587-00-00), so there's lots of used ones around:

(http://i399.photobucket.com/albums/pp74/rayivers/MX%20YZ%20MC.jpg)

I'm very happy with the two-finger operation, big stopping power, & aggressive action, but I'm definitely taking it easy the first few rides, especially in the dirt.

UPDATE:  Apparently the '09-'13 KTM 125-500 dirt bikes use a 9mm-piston MC, which would give a bit more pad pressure than the 9.5mm one above.  I didn't look, but these should be easy to find (OEM KTM, Brembo, Magura, etc.)

Ray
Title: Re: Front brake master cylinder upgrade
Post by: rayivers on August 24, 2015, 05:28:50 AM
First ride report: I was wrong - it's an excellent one-finger brake (but a little scary with two).  The lever also feels firmer with one finger, with better feedback and control.  It's great to have a firm grip on the throttle during hard braking, instead of the thumb-and-pinky crap I've done pretty much forever. :)

Ray
Title: Re: Front brake master cylinder upgrade
Post by: odedmaz on June 24, 2017, 12:00:21 PM
Hi Ray, very useful information.
If using a Yamaha MC as mentioned, what about the electrical wiring for the switch (brake light & regen). Anything I should be aware of?

Sent from my XT1585 using Tapatalk

Title: Re: Front brake master cylinder upgrade
Post by: rayivers on June 24, 2017, 06:23:07 PM
Oded,

My YZ master cylinder doesn't have a brake switch.  I'd suggest searching for 9.5mm or 9mm-piston front-MC rebuild kits on eBay to hopefully find a fitment chart, then getting an MC for a street-legal model on the chart that will definitely have the switch.

Ray
Title: Re: Front brake master cylinder upgrade
Post by: 2ballde on June 27, 2017, 01:07:35 AM
You can get a banjo bolt w/switch and use it to replace the non switch bolt on the master cylinder. Just make sure you get the correct thread. This one that might work; https://www.amazon.com/gp/product/B000GTX0XE/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B000GTX0XE/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1)