PROX Front Brake Master Cylinder Rebuild Kit for YAMAHA, KAWASAKI and SUZUKI 1997-2027

The PROX avant 37.910010 brake master cylinder rebuild kit is designed for YAMAHA WRF 250, WRF 450, YZ 125, YZ 250, YZF 250, YZF 450, KAWASAKI KX 65, KX 125, KX 250 and SUZUKI RM 65 from 1997 to 2027. This kit rebuilds the brake master cylinder (piston, cups, spring and seals, depending on the part number). Worn cups let the lever or pedal sink and cost you braking power.

Specifications

• Brand: PROX
• Manufacturer part number: 37.910010
• Weight: 40 g

When to replace it?

• Lever or pedal that slowly sinks when you hold the pressure on.
• Fluid leaking at the master cylinder.
• Spongy brakes despite a proper bleed.

Rebuild the master cylinder as soon as the lever or pedal travel gets longer for no obvious reason, or if it leaks.

Fitting tips

1. Drain the system and remove the master cylinder.
2. Remove the circlip, take out the old piston and clean the bore: it must be smooth, with no scoring.
3. Fit the new piston with its cups lubricated with fresh brake fluid, the same way round as the old one.
4. Reassemble, fill and bleed the system, then check the brakes with the bike stationary.

Why PROX?

Founded in 1975 and based near Amsterdam, ProX specialises in engine and clutch wear parts for off-road bikes. The brand has most of its range made in Japan, by OEM suppliers, for quality on a par with the original parts.

Spare parts and items to plan

• Brake fluid : MOTUL 500 ml · LIQUI MOLY 250 ml
• Brake pads : CL BRAKES · NISSIN

Frequently asked questions

Front or rear?
The kits are specific: check the position given in the product name and in the compatibility list.

Compatibility

Check the exact model and year of your bike in the list below before ordering.

Fits:
KAWASAKI KX 65 2025
KAWASAKI KX 65 2024
KAWASAKI KX 65 2023
KAWASAKI KX 65 2022
KAWASAKI KX 65 2021
KAWASAKI KX 65 2020
KAWASAKI KX 65 2019
KAWASAKI KX 65 2018
KAWASAKI KX 65 2017
KAWASAKI KX 65 2016
KAWASAKI KX 65 2015
KAWASAKI KX 65 2014
KAWASAKI KX 65 2013
KAWASAKI KX 65 2012
KAWASAKI KX 65 2011
KAWASAKI KX 65 2010
KAWASAKI KX 65 2009
KAWASAKI KX 65 2008
KAWASAKI KX 65 2007
KAWASAKI KX 65 2006
KAWASAKI KX 65 2005
KAWASAKI KX 65 2004
KAWASAKI KX 65 2003
KAWASAKI KX 65 2002
KAWASAKI KX 65 2001
KAWASAKI KX 65 2000
KAWASAKI KX 125 1999
KAWASAKI KX 125 1998
KAWASAKI KX 125 1997
KAWASAKI KX 250 1999
KAWASAKI KX 250 1998
KAWASAKI KX 250 1997
SUZUKI RM 65 2025
SUZUKI RM 65 2024
SUZUKI RM 65 2023
SUZUKI RM 65 2022
SUZUKI RM 65 2021
SUZUKI RM 65 2020
SUZUKI RM 65 2019
SUZUKI RM 65 2018
SUZUKI RM 65 2017
SUZUKI RM 65 2016
SUZUKI RM 65 2015
SUZUKI RM 65 2014
SUZUKI RM 65 2013
SUZUKI RM 65 2012
SUZUKI RM 65 2011
SUZUKI RM 65 2010
SUZUKI RM 65 2009
SUZUKI RM 65 2008
SUZUKI RM 65 2007
SUZUKI RM 65 2006
SUZUKI RM 65 2005
SUZUKI RM 65 2004
SUZUKI RM 65 2003
YAMAHA WRF 250 2024
YAMAHA WRF 250 2023
YAMAHA WRF 250 2022
YAMAHA WRF 250 2021
YAMAHA WRF 250 2020
YAMAHA WRF 250 2019
YAMAHA WRF 250 2018
YAMAHA WRF 250 2017
YAMAHA WRF 450 2024
YAMAHA WRF 450 2023
YAMAHA WRF 450 2022
YAMAHA WRF 450 2021
YAMAHA WRF 450 2020
YAMAHA WRF 450 2019
YAMAHA WRF 450 2018
YAMAHA WRF 450 2017
YAMAHA WRF 450 2016
YAMAHA YZ 125 2026
YAMAHA YZ 125 2025
YAMAHA YZ 125 2024
YAMAHA YZ 125 2023
YAMAHA YZ 125 2022
YAMAHA YZ 125 2021
YAMAHA YZ 125 2020
YAMAHA YZ 125 2019
YAMAHA YZ 125 2018
YAMAHA YZ 125 2017
YAMAHA YZ 125 2016
YAMAHA YZ 125 2015
YAMAHA YZ 125 2014
YAMAHA YZ 125 2013
YAMAHA YZ 125 2012
YAMAHA YZ 125 2011
YAMAHA YZ 125 2010
YAMAHA YZ 125 2009
YAMAHA YZ 125 2008
YAMAHA YZ 250 2026
YAMAHA YZ 250 2025
YAMAHA YZ 250 2024
YAMAHA YZ 250 2023
YAMAHA YZ 250 2022
YAMAHA YZ 250 2021
YAMAHA YZ 250 2020
YAMAHA YZ 250 2019
YAMAHA YZ 250 2018
YAMAHA YZ 250 2017
YAMAHA YZ 250 2016
YAMAHA YZ 250 2015
YAMAHA YZ 250 2014
YAMAHA YZ 250 2013
YAMAHA YZ 250 2012
YAMAHA YZ 250 2011
YAMAHA YZ 250 2010
YAMAHA YZ 250 2009
YAMAHA YZ 250 2008
YAMAHA YZF 250 2024
YAMAHA YZF 250 2023
YAMAHA YZF 250 2022
YAMAHA YZF 250 2021
YAMAHA YZF 250 2020
YAMAHA YZF 250 2019
YAMAHA YZF 250 2018
YAMAHA YZF 250 2017
YAMAHA YZF 250 2016
YAMAHA YZF 250 2015
YAMAHA YZF 250 2014
YAMAHA YZF 250 2013
YAMAHA YZF 250 2012
YAMAHA YZF 250 2011
YAMAHA YZF 250 2010
YAMAHA YZF 250 2009
YAMAHA YZF 250 2008
YAMAHA YZF 450 2027
YAMAHA YZF 450 2026
YAMAHA YZF 450 2025
YAMAHA YZF 450 2024
YAMAHA YZF 450 2023
YAMAHA YZF 450 2022
YAMAHA YZF 450 2021
YAMAHA YZF 450 2020
YAMAHA YZF 450 2019
YAMAHA YZF 450 2018
YAMAHA YZF 450 2017
YAMAHA YZF 450 2016
YAMAHA YZF 450 2015
YAMAHA YZF 450 2014
YAMAHA YZF 450 2013
YAMAHA YZF 450 2012
YAMAHA YZF 450 2011
YAMAHA YZF 450 2010
YAMAHA YZF 450 2009
YAMAHA YZF 450 2008