[ctandc]

How are you going to bleed them with the master cylinder cap off? I don't understand how that puts air in the system?

And well..every other braking system I've dealt with, if there IS air in the lines, the pedal / lever would get firmer and have less and less travel if you pump it up. Mine doesn't. Same travel with pumping or not.

[steves]

If you pump the handle with the cap off of it all you are going to do is put air in the lines. You have to bleed the M/C then put the fluid in close the cap and bleed the calipers after that.

Huh? Do you mean if the fluid level is too low?

[Teh_K]

Huh? Do you mean if the fluid level is too low?

Agreed. You kinda have to bleed the calipers with the MC cover off, otherwise you can't pour new fluid in it to replace the stuff you're bleeding out - you just need to make sure the MC doesn't run low, or else air can be drawn into the system.

[ctandc]

Actually, the brakes on both my 2000 Kat750 and 1999 Kat600 developed the exact same symptoms when I switched to your setup (rebuilt calipers, HEL 2-line kits, new pads, Speedbleeders). I did a ton of bleeding, and I still can't get the lever to engage without pulling it in a ways (more than the original setup)... I just assumed it was part of switching to SS lines, but then my friend did on his sv650 and his were SUPER solid, so now I'm like wtf...

I'm wondering...did he use speedbleeders on the SV?

I'm just a wit's end here....I mean basically I have the same brake pull I did when before I did:

- Rebuilt calipers
- Speedbleeders
- HH pads
- HEL 2 line kit
- Flush / bleed


I honestly don't know what else to do. I really don't think it's the master cylinder, but when I get a chance I'm going to switch it out to see at least.

[HS2020]

Huh? Do you mean if the fluid level is too low?

Well that will have an effect on it. What I mean is that you must first bleed the M/C. There is a step that shows that in the manual. You do that first then move onto the lines. You bleed the caliper fartherest from the M/C. Then go to the other side. and repeat. It is a pain at first but if you get a lot of air in there it takes a while to get it out. You have to get all the air out of one side then go to the next side. after the handle firms up a bit.Fill up the M/C and put the cap back on and see if you get any more air out of the system bu actually pumping the handle up a few times then having someone hold the handle and open the bleed valve and reclose after the handle goes down. This is the old way of doing it. Just like on a car or truck. I am willing to bet you will. Just watch the fluid level (2 people doing this better). If yuo understand what I am saying cool. Because I am almost confusing myself now. I had Fasher pump her hand brake up while we had the cap on to do a final bleed of the lines. Lucky for us Dapigs bike was there and both their bikes are 06 kats. So we had something to go by. After we did a final bleed on her system, her brake level travel was the same as Dapigs with the same set up. So I know your frustration. If you want to call me during the day today I will help out. I am at work but I can step outside for a few.

[ctandc]

What procedure is listed for bleeding the master cylinder?

[Black_peter]

I just winged it..
I built up a little pressure in the lever then cracked the banjo fitting, let the lever come back about 80% then snugged the banjo back up while still squeezing..

[Teh_K]

I'm wondering...did he use speedbleeders on the SV?

He did not use SpeedBleeders, so I'm thinking of switching them out for the originals, but I can't think of why they would cause the issue.

Any tips for quickly swapping out bleeders w/o spewing brake fluid everywhere? Or do I have to drain the system and start over?

[Black_peter]

He did not use SpeedBleeders, so I'm thinking of switching them out for the originals, but I can't think of why they would cause the issue.

Because they are just one thing that is not stock and influences the braking system..

Any tips for quickly swapping out bleeders w/o spewing brake fluid everywhere? Or do I have to drain the system and start over?

If you have the stock nipples all clean and ready just swap them real quick.
Fluid will ooze out but not spew. In fact if you connect a piece of hose to the stock nipple you can let the hose fill as you use it like a socket to screw in the nipple. The leaking fluid will sort of "bleed" the port.

[ctandc]

I don't even know if I still have the stock bleeders....lovely.

I've got baseball all weekend. I'm gonna try bleeding the master cylinder and see what I end up with.

[ctandc]

Well I tried bleeding it again tonight...same thing. I just bought a new (aftermarket) replacement master cylinder, it should be here by the end of the week, so we'll see what happens after that's installed.

[chinto]

sorry, I missed this thread somehow. If you haven't swapped the MC yet, give this a try. Take off the banjo bolt at the MC. Put your thumb over the bolt hole and squeeze the lever. Make sure you wear safety glasses. If you don't have a solid seal it will squirt all over. A few squeezes on the lever and you'll feel a definite increase in pressure on your thumb. Keep your thumb pressure on until you are ready for a quick install of the banjo bolt. Proceed down the lines to the next banjo (at the coupler), and so on.

[wcj]

Have you tried one of these? Worked like a charm when we had a local tech day this past weekend. Uses compressed air to siphon the caliper bleeders while the other container keeps the MC full.

[ctandc]

The master cylinder was a replacement I got a deal on when I bought the exhaust and oil pan off of a low mile (less than 1K miles) wrecked 06 Kat. My old master cylinder had a torn boot where the lever pushes on the piston and the sight glass was stained. I replaced the master cylinder when I rebuilt both front calipers, installed the EBC pads and flushed the system.

I've since added the HEL 2 line setup on the front as well.

I've used my Mityvac, and about every other combination. Including tapping on the lines / m/c to get air bubbles while bleeding etc.

The lever does NOT get tighter when I pump it up...it doesn't feel like it needs to be bled, it just travels ALOT before the brakes engage compared to a new Katana (or other bike).

I've tried pumping up the lever, and taking loose the banjo bolt to purge any air in the master cylinder as well. (Several times).

I'm going to replace the master cylinder and see what happens, it's already on the way.

[Teh_K]

Please keep us updated if that fixes it - I'm having the same issues w/ both the Kat750 & Kat600 after switching to the (pretty much) same setup you have. I have since mityvac'd an entire bottle of brake fluid thru the bikes with no improvement (and removed the SpeedBleeders, but that didn't do anything either). I've also done all the usual tapping, tilting, etc.