Front brake issues

[thedaydreamer]

Hi all
I rebuilt my OEM front brake calipers and master cylinder, I think the PO put a non OEM break line, looks braided perhaps,,,,Ive spent and entire day bleeding and these brakes will not get tight like all my other bikes, Ive bled many bikes, no issues but the feel of these OEM brakes arent good enough and the handle comes close to the grip but wont touch it,,,they will stop the bike fir sure, but the handle is looser than all my bikes, I tried all the tricks moving all over the bar,,,,

questions

Do any of you guys running OEM brake setup have nice stiff brakes?

Should I replace the MC or just the OEM brake hose?

Can I run the M109r MC, I heard you can and its better,,,not sure I want to spend on the tociko 6 pot ATM,,,,I think I can get the OEM setup working well

ANY ideas?

[Designer]

Quick Questions first so I catch up to where you now are.

When you have the lever close to the Grip. does it feel spongy at all?

Does pumping the Lever a few times help firm up the Lever's "feel" or not?

[hillsy v2]

You probably still have air in the system.

Turn the bars so the banjo bolt for the hose is lower than the mc then strap the lever back to the bars and leave overnight. Next day undo the lever and "jiggle" it in and out. That should get any bubbles out.

[Lechy]

Did you renew/replace the small "O"-ring at the caliper faces? When you mounted the caliper, were the pistons all the way back in the bodies? Open the bleeder, use a flat screwdriver to pry the pistons all the way in so they seat, Gently squeeze the lever and check if any air comes out. Re-tighten the bleeder and release the lever.

[Designer]

All good questions there, Lechy.

Best to ask such things first so as to learn more of the situation. The more one knows, the better are the suggestions of help.

[thedaydreamer]

Thank guys
Yes, I replaced the little o ring
I did a full rebuild of the seals and calipers, cleaned pistons, seated all the way upon install
the lever is about 1in from the handle, which seems too far, none of my other bikes go in that far
Im gona try the strap to handle overnight method, I did that he other day and it seemed to help, then later in the day it lost pressure, but I took it all apart and rebled so I will try again
The bike stops for sure and is ridaable,,,but I feel there should be more braking power and tension
I will report back
TY all!

[Designer]

the lever is about 1in from the handle, which seems too far, none of my other bikes go in that far
Im gona try the strap to handle overnight method, I did that he other day and it seemed to help, then later in the day it lost pressure, but I took it all apart and rebled so I will try again

Here's a method to make sure all the teeny-tiny micro-bubbles are gotten out;
viewtopic.php?f=10&t=4

[thedaydreamer]

Something Else to add
I went for a ride today, when I got to the bike cold, the handle was a little looser, however, when I squeeze a few times and hold the pressure builds, not where I think it should be, just better
When I go for a ride at a stop light, hold the brake in, let go, it feels better, but then by the next stop, its looser,,,,same process
I have the lever zip tied, if this doesnt solve it an its not air what you think next logical step, MC? brake line? I have one on order anyway, I dont like the feel of the handle on this one

ALSO
I know for the fron brank caliper the 6 pot upgrade, is there one for the rear OR should I use the OEM pad or go with something sintered perhaps for better braking power?

TY!

[hillsy v2]

Your main braking will be with the front disc - the back is not as important for fast stopping. If you can lock up the back wheel with the stock brake it is more than enough.

[sgtcall]

When you rebuilt the MC did you replace all the rubber in it? A small crack in any of the rubber will put air into the system.

[navigator]

For the hydraulics, I'd revisit the master cylinder, the rebuild kit is cheap.
I like the EBC HH sintered pads.

[thedaydreamer]

Yes, I replaced all the seals in the caliper and MC

Last night I zipped tied the handle, this AM the lever felt good, came back to the bike HR later and they felt softer

I wondering if there is a seal tear in the MC during the rebuild

I have a new MC coming anyway, bike is 24 yrs old

I think if anything Ill try that, then keep it simple by using the EBC sintered front pads, I think that the best bet for me

[Designer]

Last night I zipped tied the handle, this AM the lever felt good, came back to the bike HR later and they felt softer. I wondering if there is a seal tear in the MC during the rebuild.

Did you try the Bleeding Method I posted above?

Doing so will bring definitive results you can see. When performing that method, you will be able to see if Air in the system is the problem, because the tiny Air bubbles will appear in the Master as you do it.

And, you can test the Main Pressure Seal. After all the air is out, you can squeeze the Lever and check to see if there is a small "geyser" at the larger Hole in the bottom of the Master Cylinder. Then hold the Lever and see if it stays at the Full Pressure position. This test will check the effectiveness of the Main Pressure Seal to see if it is leaking internally.

[thedaydreamer]

No, it was late last night, so I zip tied it, pressure was good this AM when I released it, but them an HR later it apperaed to lose pressure, thats why its either air in it or a leak I think, I will try your method later today

[thedaydreamer]

So I did designers method, no air bubbles came out at any point and no further tension on lever,,,,,,it seems if I squeeze the level for 10 secs, release, it feels a little firmer, then after a min it seems to go back, I have another MC on the way, I see how that feels and will give me a direction, its an easy enough swap

[thedaydreamer]

Hey guys
Replaced the MC with a nice $26 ebay clone, very nice actually, not quite OEM tolerences but really nice and it solved the issue, front brake seems to be just right, I didnt ride it as I am rebuilding the rear caliper and adding the designer springs, dam amazon sent me the wrong kit so im waiting another week, will report back with all results,,,ty again for all your support

[Herb]

Glad to hear you have it fixed.

[sgtcall]