Topic: Better Front brake

[bryanj]

In theory to stop squealing(somewhere for dust to go) but dont work

[vik351]

Bloody hell... dont work alright, squeals like a stuck pig light braking when cold...

Heavy braking seems normal, abysmal...

vik...

[low-side]

Another consideration with braking effort is lever type.  A dogleg lever will be closer to the grip and will be easier to squeeze.  All brake hoses expand under pressure; rubber quite a bit, braided stainless very little, and kevlar even less so.

[Artie]

Ordered Bull blast MC which are 12MM thru flea bay and which post results, will probably change line too but MC first

Well almost there
the Buell blast 12 MM MC works fine on 7/8 inch bars but I cannot get all the air out of the system even with a borrowed mighty vac hook up after countless tries to bleed manually but  still have a very spongy lever no matter what I do I’ve wiggled tapped at all junction blocks and sucked thru a lot of DOT4 and still a very spongy lever
Any ideas
I did take it for a spin and nice progressive feel,it’s way better already in feel but still air somewhere HELP!!!
Thanx in advance to all the info shared
I love my K-1 they are so nice to drive
this is my fifth CB750 of various years over the years and K ones seem to me to drive and sound the best the best
Love the clean dash look
KOs to me are the best looking ,ducktail sear etc but not a fan of The plastic gauge faces
BITD I had new 70 and new 71

[rotortiller]

Might be spongy if the flex hose is expanding with the higher pressure. If you do not see air coming out during bleeding stronger tubing and/or with smaller ID might be the answer. I have bled from the bottom up using fluid pressure at the bleed nipple with good luck.

[Don R]

 Try the old rubber bands on the lever overnight trick. I added V65 calipers to my Goldwing with new lines. They were still soft after a lot of bleeding and a mighty vac. The rubber bands did the trick, the pressure compresses air bubbles and they eventually let go of the inside of the hose and fittings and float up.

[Artie]

Try the old rubber bands on the lever overnight trick. I added V65 calipers to my Goldwing with new lines. They were still soft after a lot of bleeding and a mighty vac. The rubber bands did the trick, the pressure compresses air bubbles and they eventually let go of the inside of the hose and fittings and float up.

The rubber band method seems to very slowly working but still too mushy have used it in the past with good results
got a lot of time in this seemingly simple brake bleed yikes ! We’re talking one wheel only not some car with about 2 miles of lines and 4 calipers and 16 pucks
Its come back to me now that I had similar issues with my CBX and CB 1100 F when I changed master cylinders to Z x14 type about 2 years ago
now got  two finger brakes on both but I had semi spongy issues for the longest time with the same bleed problems but not as bad 2 years later way harder barely noticed now
 still can’t quite figure it out why it can’t easily purge air
You are right It must be the compression of the air bubbles show me moving up
Maybe I’ll end up with a bit rubbery lever but good force and good feel
I can live with that and slowly gets harder over time
Need a brake expert here.
good front brakes are everything

[scottly]

Artie, try pressing the caliper piston back into it's bore with the caliper positioned so the brake hose is at the highest point; this may force any bubbles up into the MC through the tiny relief hole, instead of trying to force bubbles downhill into the caliper. The adjustment screw and spring will need to be removed first. Grip the rotor with your fingers, and press against the caliper with your thumbs, applying steady pressure.

[Artie]

Artie, try pressing the caliper piston back into it's bore with the caliper positioned so the brake hose is at the highest point; this may force any bubbles up into the MC through the tiny relief hole, instead of trying to force bubbles downhill into the caliper. The adjustment screw and spring will need to be removed first. Grip the rotor with your fingers, and press against the caliper with your thumbs, applying steady pressure.

Way in the beginning off this long process I Loosened caliper bolts a used angle pry bar and forced piston in a fair bit
will really move it in deeper removing caliper and move fluid around that way and try your method
RubberBanded over nite and a tiny less stroke still mushy
Yours is a great tip will try it again
 

[Artie]

It’s slowly making sense to me with the mushy lever
the 12 mm master cylinder piston does not displace much fluid with each squeeze and wouldnt move an air bubble very far if at all depending we’re it was trapped
Not sure why using the Mitey Vac wouldn’t suck fresh fluid thru total system?
Even tho the handles still mushy ,I like the brakes way better already
I think I’d read that in 1970 Honda Didn’t want the general public to have a front brake that would easily lock the front wheel
therefore the high effort lever and poor performance
is that true or a unfounded rumor?
To me the stock brake feels awful so wooden hard as rock worst part of the bike

[Artie]

Finally got a nice firm handle with smooth stroke and feel
After countless times Of bleeding With everything off together in every possible angle the air is finally gone
In frustration I lastly took the lever off to let MC piston come out just a skosh more and pushed piston in with punch pin,
the air might have been in the MC piston chamber and that little movement more without lever in might have been it but I don’t care now it’s over and works
I’ve heard that there a bear to bleed .....their right
The brakes are now so progressive and have great feel so nice to have a modulated lever
I’m embarrassed to admit how much time it took to accomplish this but so much better...it was worth it in the end
I’ve done the same swap on my CBX and CB1100F but using Kawasaki C14 Master 2 finger stoppy brakes
I can’t and hate to ride a bike with #$%*ty front brakes
Thanks to all who have chimed in

[Kevin D]

http://forums.sohc4.net/index.php?action=gallery;sa=view;pic=78

Here is a 40 year old original hose. It didn't leak. The bike stopped OK. This hose was replaced with black jacketed stainless braided. Check yours carefully.

[low-side]

Brake hoses break down from the inside out.  As they break down, they expand more than normal (reduced feel) and may begin to act as 1 way valves not letting fluid return to the MC.  I won't even test ride a bike with old rubber brake hoses (they're date stamped) because I don't know what they're going to do when I pull the lever.

[American Locomotive]

The outside rubber jacket of the original hoses is basically completely inconsequential to the operation of hose. You can completely strip the rubber off, and the hose would still work fine. It only serves to protect the nylon braid. What I'm getting at is that just because the rubber "looks good" doesn't mean the hose is actually any good.

On both my bike, and my buddy's bike with perfectly "fine" hoses, switching to braided stainless lines made a huge difference in brake feel.

[scottly]

Finally got a nice firm handle with smooth stroke and feel

Congratulations Artie! Sometimes brakes bleed easily, and sometimes they are a #$%*?? The important thing for others to learn is that a 12mm MC is a good fit with a single 38mm caliper.

[Artie]

Your right about that !
it makes it much nicer to ride

[Autoground]

Thank you Artie and Scottly for covering this subject here. Once I searched for MC piston, I found this thread and it was exactly what I needed. Now to measure my caliper piston.

[thebearded1]

...On both my bike, and my buddy's bike with perfectly "fine" hoses, switching to braided stainless lines made a huge difference in brake feel.

I second this! I rebuilt my master cylinder because it was leaking and took apart cleaned and reassembled the caliper that obviously helped. But after I had some ss braided brake lines made that was a big improvement in braking feel. I regularly only use 2 fingers now but am not riding super aggressively.

[jonda500]

I can see braided stainless lines helping a lot with feel and even reducing lever travel, but personally I can't see the pathway by which it can increase braking force? It wont give you stronger hands!
John

[754]

If the stock one is swelling or bulging the line, less pressure on the piston..stiffer line harder feel..