Kawasaki Twinpot Caliper Rebuild

[salty_monk]

Found this online. It's the same model brake used for the Twinpot mod so I thought it might be useful to some.

It's not completely comprehensive as I would probably go one step further & pull the pistons right out to clean the cavity behind & check for corrosion....

These 250 calipers up to about 2006 are a good source of spare parts as you can often find ones in great condition (just for the right hand side so use one on the right & use the parts from a 2nd one to rebuild an older Left hand from a Ninja 600/750 or an EX500).

http://faq.ninja250.org/wiki/Brake_caliper_rebuild

[greg78gs750]

thanks for that link, dan!

greg

[Chuck78]

Nice one, thanks again Dan! My bike will be getting my twinpot mod here in the next 2 months, as we are doing a big West Virginia/Virginia/SouthEast Ohio mountain/twisties/scenic road trip. This appears to work for a single disc upgrade also if you use the single disc fork leg and a 22mm offset CBR1100 Blackbird 310mm rotor and the Ninja 250 left caliper. My wife's bike will be getting this. I'll let you know how my modified Tokico brakets turn out, using 1 spare bracket to chop and weld half of it to the full brackets. Thanks for all of your help, and the other guy you developed this mod with.

What are everyone's thoughts on going with a used 2000-2006-ish Ninja 250 single left caliper and robbing the used seals for rebuilding one or both of the older calipers, versus $50-$60 for 2 brand new rebuild kits? The used calipers I got both were the cleanest looking ones at the motorcycle junkyard, and I am debating on whether or not to tear them down and rebuild. No idea what years they came off of, they were in a parts bin of calipers...

[Big T]

Chuck,

You should pop out the pistons and clean the bore

If the seals are good, clean all the caliper parts and reassemble

If they're good, a couple of bucks for brake clean and brake grease

[Chuck78]

Just saw this reply two months later as I was about to work on my used calipers. WOW was I glad I tore those apart! the pistons on two of three were pretty stuck in there from all the crud and varnish, even on the clean looking caliper! The seal grooves in the piston bore were just caked with varnish and the outer one with tons of crud. an hour per caliper with the dental pick, toothbrush, brass wire brush, brake cleaner, and silicone to clean. A lot of the varnish I attribute to them sitting in a parts bin on the shelf at the local junkyard for ages, drying up, but that stuff was mostly behind the seals. One caliper had a layer of that in the piston bore on one spot.



One caliper seal groove also had some minor pitting, not the whole width of the seal groove, but I am a little cautious. I'm going to try and run it as is and see how it does.

Out of 12 seals, only one outer seal failed my visual inspection, and that was off the one labeled '88 EX500 Ninja.

Popping the pistons out required me flooding them internally with silicone lube spray and using the rubber tipped blow gun on the compressor. once the first one pops out, quickly clean and lube and reinstall it, then brace it in with a 3/4" block of wood to keep it in the hole and force the other piston out. keep fingers clear or you'll crush your fingertip like I did once! Ouch

[Chuck78]

This Permatex Ultra Disc Brake Lube works AWESOME for installing pistons and seals, and is good for the pins and external contact points as well. It specifically says that it's brake fluid compatible and good for piston and seal installation lubricant.