Topic: DUAL-DISC SETUP INSTALLED --> NOW RUBBING ON ROTORS !!!!!!!!!!!!!

[ProTeal55]

Hey,

For those of you who arent aware, I have been fighting with this dual-disc setup to get it finished.
First it was leaky lines that was the issue.  >:(Then the master cyllinder I had was pushing more air than fluid.
Then with the addition of clip-on's the line from the master to the "Y" fitting was to long.

SO, Today I worked a 1/2 day, and wanted to give the bike my all to get it done. I get the new ($130, which does have a built in brake switch by the way) master on the bike, bleed the system, and OH MY GOD, The brake lever has pressure  . So now I get all excited, put the exhaust back on, tidy up some  loose ends, etc so I can take it for it's maiden voyage.

I go to push the bike outta the garage, and it won't move ..I looked to see if something was in-front of the tire, nothing their. Seems as if the caliper(s) are not releasing from the rotor as they should, after the brake lever is let go. Another issue with this damn setup ! 
I played with the adjusting spring thing on each caliper for awhile , and it got alittle better. I decided to take it for a slow/careful jont around the block, to see if it would get anybetter, it did not. I did realize that a cafe style seat is in my future, as those clip-on's might look cool, but are gonna bust my back !

So fellow CB'ers, what do I do now ? Where should I start ? What is the issue ?

All I wanna do is ride the damn thing 

[Chris Liston]

"could be" that the piston may have gotten off axis, it does happen.   Happened on my bike last year when I installed a new piston/seal.  I had to take it all apart and very carefully insure then when I pushed the piston in it was centered.  Helps to lub the piston with brake fluid too.   I feel your pain.

[putnaja1]

I just have to say two things about this:

1)  You are WAY too far along now to quit!  Come on man, you can lick this thing!  Let's see the fruits of your labor dude!  You can't be far now!
2)  Where are you finding these incredibly hot women for your avatars!?  Great gazongas!  :-)

Jason

[hcritz]

Hey Proteal...
Does your new MC have any adjustments for the lever stop???
If the piston there doesn't come all the way back and uncover the relief port it will hold residual pressure in the system.
Just a thought....
ED

[Magpie]

You beat me to the lever question, is the master cylinder allowing the fluid to return when you release the handle and are the brake pistoins very clean and rust free? If there's anything on the surface of the piston it may be hanging up on the seal and not releasing the pressure on the rotor.
Cliff.

[bwaller]

Hey PT,

Sounds like at least one caliper is binding, or at least one piston won't retract. I think I remember reading you bought this front end with the dual disc set-up. Did you clean up the calipers?  Eyeball from the front, do the calipers seem parallel with the legs and discs? If so try again to adjust the 6mm screws on each caliper bracket to gain some free play between the pads and the discs. If you have difficulty getting any back the screw off a couple turns and attempt to push the caliper against the disc. Ordinarily this will retract the piston enough to get some slack. If you don't get any movement, the piston & caliper seal is probably corroded and preventing retraction. Try both sides. If it seems this is the problem, let us know, there maybe a couple shortcuts to the teardown.

Good luck and if you rebuilt the calipers you can tell me to go to hell, I've heard that before!  

[bill440cars]

             Hey ProTeal,  Just another interested and concerned guywho knows that you can't let
     this thing get the best of you. You have come along way with this project and I'd sure hate to
     see you throw in the towel. As far as the clip-ons go, I tried them myself, when I was about 20
     yrs old, on a 66' CB72 Hawk and just flat couldn't get used to the lack of leverage and bent over
     like I was riding a 10sp bicycle. I know I'm basically repeating what's already been said but, I really
     hope you'll "Back off, regroup, go through the front brake system (check it out thoroughly) and   
     hopefully, you'll find your problem/s. This is one tough bike and when things fall into place then,
     hopefully, you can enjoy a good long ride.

               Once, when I was in my teen years, I was having problems with my bike and I was getting
     mad fast. Nothing was going right and I was gettin short tempered was a couple of the men
     nearby. My Dad took me up to the front of my Grandfathers motorcycle shop, told me to get a
     coke, sit down and cool down. then I could go back and try it again. It worked with me. You
     need to clear your head and then go through it from one end of the brake system to the other.
   
               I wish you the best of luck, hope you can stick with it and clear this thing up. Take care &
     I'll catch you later on,  Bill   

[ProTeal55]

Hey Proteal...
Does your new MC have any adjustments for the lever stop???

Yes , their is a "silver circle" that has numbers 1-4 on the master, near the brake lever. Could this be applyin to much pressure ? I am new to these "high tech" parts  I got the new master from ----->http://www.speedwerks.com/catalog/c0m0bm0b0s1pn0p4182np0 Got it in less than a week , cant complain about that ...

1) You are WAY too far along now to quit! Come on man, you can lick this thing! Let's see the fruits of your labor dude! You can't be far now!
2) Where are you finding these incredibly hot women for your avatars!? Great gazongas! :-)

1. I know I am too close to give up, but it is at the point where all the fustration and money I am throwing at this thing just isn't worth it. I should have the entire project finished by next week, with some help. I will post some pics of the progress today or tomorrow..
2. That lovely lady is a model for Sucker Punch Sallys. I actually met her before, here name is Kristen, and is a lovely specimen. Awesome girl, outstanding body, rides a hardtail bobber, etc..I would say more about our "encounter" but my girlfriend (not Kristen) might happen to read this topic 

As far as the clip-ons go, I tried them myself, when I was about 20
 yrs old, on a 66' CB72 Hawk and just flat couldn't get used to the lack of leverage and bent over
 like I was riding a 10sp bicycle.

I was on the bike yesterday for about 5 min, doing some shakedown passes up and down the street,and I allready felt the "strain" that the clip-on's are gonna give me. I am gonna try and get used to them, because they look too badass to get rid-of at the momment. The bike is def. comming togther, just itching to ride the thing , and get all the loose ends fixed up and done. As far as "walking away to clear my head", I am a big fan of that, and do it allot. Was easier when I still smoked the good ol' marlbro reds, but now I just grab a beer/pop/crown royal & coke and reflect on what I need to do to fix the issue in front of me.  never said I had paietence, and as I get older (26 now) , I am unsure if it is getting better or worse..

You beat me to the lever question, is the master cylinder allowing the fluid to return when you release the handle and are the brake pistoins very clean and rust free? If there's anything on the surface of the piston it may be hanging up on the seal and not releasing the pressure on the rotor.

The master on the bike is brand new, right outta the box. I am not sure if it is indeed letting fluid return or not, thus my questions on the little "silver circle with numbers on it" , which is right near the brake lever itself. As far as the calipres go, I was told that both of them were both rebuilt, but who knows. Maybe I need to rip them apart, maybe the problem lies in the master being new and 'stock" , not sure. I do know the bike is a different animal with the 21'' front wheel and clip-ons, and I wanna RIDE !!!

[MRieck]

 ProTeal  The silver circle with #'s lets you adjust how closeor far the brake lever is from the grip. It doesn't effect anything else though the closer the the lever is to the bar the leverage you have. It isn't your problem. I have run the same master for several years with no problems at all. It sounds like a caliper/rotor clearence problem to. As someone said...the pads have to be parallel to the rotor with proper clearence between the rear pad/rotor most important. Try loosening the front axle clamps,caliper arm clamps and arm adjustment screw and place the front wheel against a wall and bounce the front end about 6 or 8 times to align everything and tighten it up. Get the front end off the ground and start from there.

[ohiocaferacer]

That lovely lady is a model for Sucker Punch Sallys. I actually met her before, here name is Kristen, and is a lovely specimen. Awesome girl, outstanding body, rides a hardtail bobber, etc..

....DAM....and they(SPS) are in Ohio.

Had never heard of them........Miamisburg is close to me!!

Later......off to find Kristen!!
Greg

[ericstew]

I had a similar problem with a 750F1
When you open the master cylinder top you should see 2 holes:
1 to allow the fluid to go throught while pumping
2(very small) which let fluid coming back once you stop pumping
On my bike the small hole was full of s... the pressure was still applied on the brake!I just could move the bike!!!
Anyway it's a 5 second check...Good luck

[ericstew]

I meant I could NOT move the bike just like you!
After cleaning the hole with a tiny drill everything went back to normal

[ProTeal55]

OHIOCAFERACER--->
If you come across Kristen, tell her Joe Caccavella from Chicago said hello 
ERICSTEW---------------->
The Master on the bike is brand new, and i am 100% positive in working order as it should be.
The issue has to be in the calipers, as far as the piston(s) not retraciting/Calipers not aligined on the
rotors. I am not gonna ride it anymore untill this issue gets resolved, as the last thing I need is to ruin something/warp a rotor..

[chippyfive50]

That lovely lady is a model for Sucker Punch Sallys. I actually met her before, here name is Kristen, and is a lovely specimen. Awesome girl, outstanding body, rides a hardtail bobber, etc..

....DAM....and they(SPS) are in Ohio.

Had never heard of them........Miamisburg is close to me!!

Later......off to find Kristen!!
Greg

SPS'S is in MIAMITOWN OH, 15miles NW of cincinnati (about 3 miles from my house). They just had a bike in THE HORSE mag with another "lovely specimen" onboard.
MY EYES WILL BE PEELED at the local shows this summer...
 

[crazypj]

The rear pad (fixed in caliper) should have 0.006" clearance, adjust with the screw on fork leg and a feeler gauge
Do you have a front mudguard (fender) fitted?  Is the caliper mount flat on fork leg and parallel to the rotor?
PJ

[skidpan]

Are the piston seals sat properly in their grooves?  Having a piston not retract could be down to a seal not in quite as it should be, or, more likely, a build-up of gunge in the groove the seal goes in, causing the seal to pinch the piston too tightly so the negative hydraulic pressure when the lever is released is not being enough to overcome the seal/piston drag.

[ProTeal55]

I am gonna tear into the calipers on sunday, and see whats going on.
I was told that both were just rebuilt, so maybe a seal is in the wrong place or something.

Anyone in the chicagoland area that wants to make a few bucks and help me sort this issue out

[cben750f0]

mate i had the same prob when i did the set up on my bike... the problem then was that the caliper arm, was not parallel to the disc, and when the brake was aplied the pad would jam in the caliper, take the caliper off, (leave it on the brake line), and put a straight edge on the disc, and see if it is parallel to the caliper arm, i found that the two fork legs arent the same when fitting the caliper arm, b/c honda never intended to put another caliper on, so the mount points are not finished.

     this was my only hassel with my set up, and when i filed and shimmed the caliper arm so that it was parrallel to the disc everything was sweet... BTW i have a doco in FAQ about the duel disc change if that helps..... peace mate...

[MRieck]

mate i had the same prob when i did the set up on my bike... the problem then was that the caliper arm, was not parallel to the disc, and when the brake was aplied the pad would jam in the caliper, take the caliper off, (leave it on the brake line), and put a straight edge on the disc, and see if it is parallel to the caliper arm, i found that the two fork legs arent the same when fitting the caliper arm, b/c honda never intended to put another caliper on, so the mount points are not finished.

     this was my only hassel with my set up, and when i filed and shimmed the caliper arm so that it was parrallel to the disc everything was sweet... BTW i have a doco in FAQ about the duel disc change if that helps..... peace mate...

I'm sure cben is right on this.

[bsanorton]

I'm working thru this same problem as you write this. I narrowed it down to one caliper piston hanging up (the right side one, the add on one) even after taking apart & cleaning. When I tapped the bad caliper with a rubber mallet it allowed the piston to release a bit. Took the caliper apart once more, this time I used a new piston & seal & proper silicone grease, cleaned out the seal area real well with a brass wire brush. I knew it was better immediately after feeling the way the piston slipped into the caliper on reassembly. So far no binding, but have to do final bleeding this morning. The alignment is a pain (especially after I didn't take pictures of the way the spacers were placed originally, duh!!!), one caliper side uses washers as spacers & one side uses the fender mounting bracket. 
Was gonna post a pic, but can't figure out how, I'll have to search the site.

[cben750f0]

http://www.sohc4.us/forums/index.php?topic=2582.0.. have a read of this... hope it helps... peace

[bsanorton]

Very good reading. In my case I didn't realize the two sides were different in respect to the mountign of the fender & the alloy casting of the brake arm. If I did, I would have taken pictures of the spacing BEFORE taking it apart. I am studying your pictures for the proper alignment & think I have it. Sorry, ProTeal, don't mean to hijack your thread, but I'm working in parallel with you, LOL!!!! Have you posted pics of your handlebar setup yet?

[bsanorton]

With fender. I think I'd like to do what Pro did with respect to the fork brace & utilize the fender internals.

[ProTeal55]

Have you posted pics of your handlebar setup yet?

Check out some recent pics here---->  http://www.sohc4.us/forums/index.php?topic=9212.0

[bsanorton]

Damn fine scoot!!!! Good luck with the brakes.