NX250 brake caliper maintenance
Verfasst: Sa Sep 05, 2020 7:59 am
Disclaimer
If you have never worked on the brakes before, a knowledgeable friend should help you
The Nissin calipers used in our NX250 and many other Honda dirt bikes with 240mm brake discs (e.g. XL600R, some XR250, XR600) have a tendency to jam. Dirt gets behind the outer dust seals and the pistons then go back more and more difficult. In addition, a hard coating forms on the pistons, which damages the dust seals when the pistons are pushed back. When changing the brake pads you should clean the pistons before they are pushed in.
To do this, press out one piston at a time (usually only one will move anyway, otherwise secure one with a clamp) with the handbrake lever a bit (not too much or the piston will fall out) and clean it with some brake cleaner and for instance with pipe cleaners https://www.amazon.com/Smoking-Cleaners ... P6Z1NT2YQS.
When the piston is clean, a bit silicone brake lubricant (seal kits often include that pink or orange stuff https://www.ebay.com/itm/2FastMoto-Fron ... SwmtJXUI5G) can be applied to reduce the friction of the dust seal. The clean piston now only has to be pushed back with finger force. If you need a clamp, the dust seal is very likely already damaged and must be replaced.
The clean piston is secured with a screw clamp, then the other piston can be pushed out and cleaned.
During the entire process, the fluid level in the brake cylinder reservoir should be monitored. Suck brake fluid from the reservoir with a syringe before it overflows.The level should also not fall below minium, otherwise air could be forced into the brake line. And after changing the brake pads you should also change the brake fluid.
The two sliding pins of the brake caliper need a little grease (preferably special heat-resistant grease for brake callipers) so that the brake runs smoothly again. And the screw pin and the cover cap should get some anti-seize lube ceramic paste and the tightening torque should be observed. Otherwise it will be very hard to remove the pin / cap the next time when changing the brake pads. Many brake calipers were ruined because pin /cap could not be removed.
If you have never worked on the brakes before, a knowledgeable friend should help you
The Nissin calipers used in our NX250 and many other Honda dirt bikes with 240mm brake discs (e.g. XL600R, some XR250, XR600) have a tendency to jam. Dirt gets behind the outer dust seals and the pistons then go back more and more difficult. In addition, a hard coating forms on the pistons, which damages the dust seals when the pistons are pushed back. When changing the brake pads you should clean the pistons before they are pushed in.
To do this, press out one piston at a time (usually only one will move anyway, otherwise secure one with a clamp) with the handbrake lever a bit (not too much or the piston will fall out) and clean it with some brake cleaner and for instance with pipe cleaners https://www.amazon.com/Smoking-Cleaners ... P6Z1NT2YQS.
When the piston is clean, a bit silicone brake lubricant (seal kits often include that pink or orange stuff https://www.ebay.com/itm/2FastMoto-Fron ... SwmtJXUI5G) can be applied to reduce the friction of the dust seal. The clean piston now only has to be pushed back with finger force. If you need a clamp, the dust seal is very likely already damaged and must be replaced.
The clean piston is secured with a screw clamp, then the other piston can be pushed out and cleaned.
During the entire process, the fluid level in the brake cylinder reservoir should be monitored. Suck brake fluid from the reservoir with a syringe before it overflows.The level should also not fall below minium, otherwise air could be forced into the brake line. And after changing the brake pads you should also change the brake fluid.
The two sliding pins of the brake caliper need a little grease (preferably special heat-resistant grease for brake callipers) so that the brake runs smoothly again. And the screw pin and the cover cap should get some anti-seize lube ceramic paste and the tightening torque should be observed. Otherwise it will be very hard to remove the pin / cap the next time when changing the brake pads. Many brake calipers were ruined because pin /cap could not be removed.