5th gen Braided Brake Line Options - Advice and Opinions Wanted

Can anyone confirm that the master cylinder bleed/ return hole is a straight shot down into the area that the spring occupies? No turns or anything that may block a wire from clearing the hole from the resevoir?

Mello dude's suggestion to rebuild the master may be the real issue as I think about it. It may be that the push rod/ seals assembly is not fully returning and the speedbleeders when opened do not "bleed" because the hydralic pressure is very light at that point but enough to make the brakes drag.

 

I recently put an old but lightly used front wheel and new pads in my VFR and was astounded at the drag. So I disassembled all the parts and reassembled and checked everything was smoothly moving, and I still had a lot of drag. In the end I concluded the dics had been sitting long enough to form a reasonable layer of corrosion, and just went riding. After a few miles the drag was gone...

 

You may be on to someting that makes sense Terry.

The discs are a used set that I purcased from a facebook listing. They are not yet to the minimum thickness specification, and are not warped. Before installing them on the rim I cleaned them with brake cleaner, and scrubbed them with a 3M Scotch-Brite pad. I have, however, not changed out the pads. I wonder if my used pads (which have plenty of pad left yet) are worn at an angle, and may be forcing the pistons to bind when enough pressure is applied.

 

The synapsis that are happening in my brain are forcing me to conclude that the master cylinder is not the problem.

Mello's suggestion of checking each caliper indiivdually turned my thoughts back to the multiple times that I forced the calipers apart to see if one or the other was dragging more. Every time that I did that, the other caliper continued to drag. In other words, I would pump the brake lever multiple times giving it full brake pressure. After releasing the lever, I would attempt to spin the tire and wheel. Grasping the tire and spinning it as hard as I could would only result in a quarter of a turn of the tire after my hand let go of it. This has not changed after a few hundred miles, and the new lines. Following the spin test I have pressed one of the calipers to release the pad from the disk. No matter which one was release the other was still dragging.

Thinking through the above "test", wouldn't both of the calipers release when forcing one of them to release if the problem was residual fluid pressure? Both calipers share the same pressure, so when one of them is pressed apart, the shared pressure would be released. Therefore the dragging of the caliper is not a result of trapped or unreleased brake fluid presssure, and the issue must be in the caliper/ pad/ disc area.

 

Long overdue update to this thread!

Following up on all of the previous "head scratching" with more, I removed the calipers from the forks again.

The next, and seemingly last area that I could think would be causing the draggging brakes was the pin and rubber boots that the caliper assembly "slides" on. I removed the rubber boots and cleaned them of all grease and whatnot. Then lubed them with a light coating of sinthetic grease, and reinstalled the calipers.

Finally I have had some improvement. I have been able to use the front brakes with full pressure, and after a ride when I touch the disc on either side of the front wheel, I have found the discs to be at a resonable tempature. In fact, if I have used the brakes lighly in the last few miles, the discs are rather cool, I believe that the boots have swollen because someone used the wrong type of grease to lube them. I plan to order new replacements, then install them in the off season.

I also installed the 14mm master on the rear after I rebuilt it using a kit purchased from BrakeCrafters as Mello suggested earlier. It is "night-and-day" different with the delinked rear using all three pistons and the 14mm master! I can lock up the rear if I so desire. Much more feel and control.

In hind sight I don't think that the original rubber brake lines were shot nor causing issues. It seems to have been caused in large part by a previous owner probably using the wrong type of grease on the rubber boots, causing them to swell a bit and "bind" the calaper pins.

 

Here are a few photos of the new lines installed.