Author Topic: Question about front break line  (Read 1363 times)

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Offline mhsull

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Question about front break line
« on: July 09, 2012, 03:02:09 PM »
I had to remove my front forks to put gaitors and new fork ears on yesterday.  When I went to disconnect the break line at the frot wheel, I unscrewed the nut am the break fluid started leaking out.  I didnt think that removing the font wheel meant draining the brake fluid so I quickly screwed it back in and looked for another place to disconnect the line.  I then decided to unscrew it at the base of the triple tree.  Some fluid came out there but not as much so I left it unhooked and screwed that bolt back in. 

After all was done, I put everything back together but my front brake has not worked since then.  I saw that my brake fluid was noticeably lower in the reservoir on the handlebars but I don't know how much it is supposed to have.  Is it possible that I just need to refill the reservoir to get the brake to work or do I need to look elsewhere?
1977 CB750K

Offline madmtnmotors

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Re: Question about front break line
« Reply #1 on: July 09, 2012, 03:06:57 PM »
You've let air into the system. Top off the resevoir and bleed the system until you get the air out, checking the resevoir periodically as you bleed the system to prevent introducing even more air by letting the resevoir run dry as you bleed the system.

easy-peasy
TAMTF...


Wilbur



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Offline MCRider

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Re: Question about front break line
« Reply #2 on: July 09, 2012, 03:14:15 PM »
First what you did wrong. You would not break the line anywhere along the route, as you discovered fliud will come out. to get the fork off you would unbolt the caliper from the leg, leaving it attached to the line.

Now that you have broken the line, you must back up and regroup. The MC should have a level line in it. Remove the rubber diaphragm to see it, fill to the line, replace the rubber and the cap.

By breaking the line you have allowed air into the system. You need to do a standard bleeding operation per the manual. Remov the cap and diaphragm. Pump the lever twice, loosen the bleeder valve at the caliper. YOu'll feel the lever get closer to the grip, close the valve. Release the lever and pump again slowly. Fast pumps and releases will cause a squirt of fluid to jump out. Bad on paint. Cover your tank with a towel.

Rinse and repeat. You can put a hose (clear is nice) on the bleeder valve to contain the mess and watch for air bubbles to come out.  Refill the reservoir as needed.
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline mhsull

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Re: Question about front break line
« Reply #3 on: July 09, 2012, 03:22:54 PM »
This is a huge help.  Thank you.  I wasn't sure where to disconnect the break.  The "what you did wrong" is what I love to see as to ensure it seamy happen again.
1977 CB750K

Offline MCRider

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Re: Question about front break line
« Reply #4 on: July 09, 2012, 03:25:10 PM »
This is a huge help.  Thank you.  I wasn't sure where to disconnect the break.  The "what you did wrong" is what I love to see as to ensure it seamy happen again.
Thanks for taking it the way it was intended, as help.

I see by your post count your relatively new, welcome.
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline Duke McDukiedook

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Re: Question about front break line
« Reply #5 on: July 09, 2012, 03:36:38 PM »
Brake, not break.
"Well, Mr. Carpetbagger. We got somethin' in this territory called the Missouri boat ride."   Josey Wales

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Offline lucky

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Re: Question about front break line
« Reply #6 on: July 09, 2012, 08:46:03 PM »
Brake, not break.

You beat me to it. I read that same misspelling a lot on the internet.
The one that bugs me  is prolly.

Offline tomkimberly

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Re: Question about front break line
« Reply #7 on: July 09, 2012, 10:56:13 PM »
Brake, not break.

If you understood him, why the spell check?   8)

Offline flybox1

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Re: Question about front break line
« Reply #8 on: July 10, 2012, 06:57:41 AM »
just wait until he asks for help with cleaning his crabs  ::)
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Offline Duke McDukiedook

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Re: Question about front break line
« Reply #9 on: July 10, 2012, 07:51:59 AM »
Brake, not break.

If you understood him, why the spell check?   8)

Because he did it multiple times so to me he thinks that is the proper spelling.

Think of it as real karma as opposed to I don't have the money to buy some fake ad bike cheap so I'll alert the fake seller to the "real value" to feel good karma.
"Well, Mr. Carpetbagger. We got somethin' in this territory called the Missouri boat ride."   Josey Wales

"It's Baltimore, gentlemen. The gods will not save you." Ervin Burrell

CB750 K3 crat | (2) 1986 VFR750F