[LaGrasta]

I rebuilt my front caliper years ago, but just started riding the bike recently. My front brakes keep dragging so I finally tore them apart again, pulled the pistons out and found them to have good looking seals but slightly pitted pistons. Advice?

 

[reclinedrelic]

How clean is the groove in which the seal sits? Debris there puts extra pressure on the piston and may cause problems with retraction. If the chrome is flaking around the pits that can also cause piston drag. Considering the importance of proper braking I would suggest replacing the pistons.

 

[bahn88]

Replacement pistons are available in stainless steel.....

 

[danroy323]

I rebuilt my front caliper years ago, but just started riding the bike recently. My front brakes keep dragging so I finally tore them apart again, pulled the pistons out and found them to have good looking seals but slightly pitted pistons. Advice?

4into1.com has them for not much money. Rebuild kits too…

Brake Caliper Piston - 45107-MA3-006 - Honda CB400/450/650/750/900/1100 CM400/450 CX/GL500/650 VF700/750/1100 CBX GL1100

Reproduction front or rear brake caliper piston for the Honda models listed. Check the fitment list carefully as some models changed brake caliper pistons in different years.

4into1.com

 

[LaGrasta]

thanks guys, appreciate your insight. I'm making a purchase now…

 

[LaGrasta]

After shopping around, 4into1.com is the cheapest, as there are very few stores selling the piston at all, or even the seals for that matter. It cost me $100 to fully rebuild both front GL calipers. Thanks again.

 

[danroy323]

After shopping around, 4into1.com is the cheapest, as there are very few stores selling the piston at all, or even the seals for that matter. It cost me $100 to fully rebuild both front GL calipers. Thanks again.

This is what I found out too, even after accounting for shipping to Canada 4into1 came out as the best place for brake parts. I also got braided brake lines and a master cylinder from them too.

 

[baggo]

I rebuilt my front caliper years ago, but just started riding the bike recently. My front brakes keep dragging so I finally tore them apart again, pulled the pistons out and found them to have good looking seals but slightly pitted pistons. Advice?

Clean calipers, new seals and stainless steel pistons, new flex brake hose or hoses. The hoses will cause the brakes to drag. Make sure master cylinder is clean and fluid is returning after pulling on brake lever. small return hole can clog up.

 

[LaGrasta]

"The hoses will cause the brakes to drag" is this true, never knew this. Mine are original but appear so good (SoCal climate), I've kept them.

 

[danroy323]

"The hoses will cause the brakes to drag" is this true, never knew this. Mine are original but appear so good (SoCal climate), I've kept them.

They can collapse or delaminate inside. Fluid under high pressure from the master cylinder can still pass and actuate the brakes but upon releasing the brakes the fluid can't back towards the master cylinder causing a partial pressure to remain in the caliper causing brake drag.

 

[danroy323]

They can collapse or delaminate inside. Fluid under high pressure from the master cylinder can still pass and actuate the brakes but upon releasing the brakes the fluid can't back towards the master cylinder causing a partial pressure to remain in the caliper causing brake drag.

New hoses from 4into1 or other places are not that expensive.

 

[Sidecar Bob]

Rubber brake lines should be replaced every 2 or 3 fluid changes (=5 or 6 years).

Have you ever wondered why brake fluid discolours after it has been in the system for a few years? It is a combination of tiny particles of rubber plus the fluid oxidizing because the rubber is porous and a certain amount of moisture (again through the rubber.

Stainless braided lines (actually teflon tubing with stainless wire braided over it for protection) last practically forever and double the fluid change interval. And when you do change the fluid after it has been in the teflon tube for 4 or 5 years it will look a lot cleaner than fluid that was in rubber lines for less than 1 year.

It always amazes me that people make all sorts of modifications for the sake of style and then ignore the ancient brake lines.

BTW: Did you ever check the return hole in the master cylinder?

 

[D-Fresh]

It always amazes me that people make all sorts of modifications for the sake of style and then ignore the ancient brake lines.

+1 on that point Bob.

Or why people will rebuild calipers/replace MC but not lines?

 

[bahn88]

+1 on that point Bob.

Or why people will rebuild calipers/replace MC but not lines?

Yeah...one of my friends had a Ducati 900SD...2 professional engine rebuilds to "race spec" ($15,000Aud) but original brake lines...
I suggested stainless lines.. but a week after fitting the bikes big end went....
No not cause and effect...lol..but questionable priorities.....

 

[LaGrasta]

After I attached my new (generic) brake lines, I cut open one of the originals. Turns out, braided stainless, with black rubber overtop. No wonder people keep using them, they were built well from the factory.

 

[Sidecar Bob]

I've cut through old factory brake lines a few times and I've never found steel (stainless or otherwise) in any of them.

Please post a pic of the end of one of your old lines with the fitting on it.

 

[bahn88]

There is braided stainless with classic black look...mine are HEL but glossy...theres matt as well...

Are you sure its metal and not just cord in the old lines??

 

[LaGrasta]

i'll post a pic, when i get back home this evening. these are braided, but look like normal OEM thick black lines.