Front brakes wont stay bled and whats the best front stainless brake lines

nerfbars

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I have a 01 Busa and every spring after sitting all winder my front brake lever bottoms out and the front brakes dont work. After you bleed them they work fine all season... until this past year. This past spring i bled them and they wont stay bled now. There are no fluid leaks. I assume i have a leak large enough to suck air but too small to leak fluid. Before i gonand rebuild the front calipers and master cylinder i think im going to change the factory front brake line and put a new set of stainless lines on it. This should eliminate the lines and copper gaskets from the potentional source of the leak. Has anyone had a similar experience and what lines do you reccomend? Im currently planning on buying a Galfer set. Thanks!
 
I’ve used Galfer lines for years on several bikes with no problems, including my Busa. I’ve also learned that everything mechanical has to be ‘exercised’ and left unused for periods of time take a toll on their reliability and longevity. Braided SS lines are really Teflon tubes wrapped with meshed SS which help prevent hose flexing. OEM hoses are just rubber and flex quite a bit.
 
The air that accumulates in your brake system over the winter period is most likely coming from the moisture in your brake fluid.
Brake fluid is 'hydroscopic' (look that up) and attracts moisture from the atmosphere quickly and easily.
If you live in a fairly humid/damp area, or even store your bike in a damp garage or shed, this will only exacerbate the situation.
The brake reservoir cap is vented to atmosphere and allows moisture to accumulate in the fluid. Then the oxygen in the moisture separates and forms air bubbles in the system and eventually bigger air bubbles appear and the lever goes 'spongey'.
I suggest flushing and renewing all the brake fluid and sealing the brake reservoir by sealing the vent in the lid. to make it air tight while in storage. This will prevent air/moisture getting in to the system and causing the same problem.
One thing though . . . DO NOT forget to clean out the vent in the cap before riding it!!
Also, change the brake fluid regularly, this means pumping new fluid thru the system and getting rid of ALL the old fluid. Your brakes will thank you for it, and it only takes half an hour to do.
 
I need to clarify re the venting of the cap . . .
the cap is vented to allow the 'bellows' rubber seal to move up or down, as the fluid moves in the lines when the brake is applied or released.
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1547544949518.png

Also, the fluid level in the reservoir will drop as the pads wear, and the pistons in the calipers move out little by little to take up the wear.
So moisture gets past the rubber bellows and into the fluid because it is not a perfect seal to start with and over time the rubber bellows' edges distort in shape and fitment, losing even more of the sealing.
I hope this helps.
 
Worth doing the MC like Tool said. It can get pretty corroded in there it is just a spring few seals and piston. Clean it all out real well put the new parts in it may help to lay out the old parts or take a picture of the setup. Remember the c-clip goes on with the flat side pointing outward. If you feel/look at both sides one is flat the other is slightly rounded. You may even be able to clean and keep the old parts as spares.
 
Brake systems are not hard to deal with, just basic hydraulics at work, and maintaining the system, changing fluid regularly, lubing pivot points, checking and replacing pads when necessary, upgrades such as braided hoses, are all it takes to keep your brakes working as well as they did the day it rolled off the production line.
 
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Just an fyi, I had a Bking(hydraulic clutch, same as Busa), and the clutch would not stay bled.
Air was definately getting in somewhere.
After searching to no end, finding nothing, I replaced the clutch line...problem solved.
The brake/clutch lines are multi-layered, and it IS possible for them to have a small enough hole in one of the layers that lets air in, but also doesn't let fluid out.
I had a hard time beliving that until the line replacement proved it.
I had rebuilt the MC first as well, which is usually the first and best place to start.
Next I did the piston seal in the sprocket cover, and bled multiple times.
No change, until swapping the lines.

Also, on any brake/clutch line bleed, bleed them until they function normally. Then, pump the lever and zip-tie it around the handlebar(use cardboard around the grip and lever to prevent any damage).
Let it sit 12-24 hours, then bleed again.
There will be more air to come out.
Sitting overnight with pressure on the brakes makes any air left easily bleed out.
Done.
 
Just an fyi, I had a Bking(hydraulic clutch, same as Busa), and the clutch would not stay bled.
Air was definately getting in somewhere.
After searching to no end, finding nothing, I replaced the clutch line...problem solved.
The brake/clutch lines are multi-layered, and it IS possible for them to have a small enough hole in one of the layers that lets air in, but also doesn't let fluid out.
I had a hard time beliving that until the line replacement proved it.
I had rebuilt the MC first as well, which is usually the first and best place to start.
Next I did the piston seal in the sprocket cover, and bled multiple times.
No change, until swapping the lines.

Also, on any brake/clutch line bleed, bleed them until they function normally. Then, pump the lever and zip-tie it around the handlebar(use cardboard around the grip and lever to prevent any damage).
Let it sit 12-24 hours, then bleed again.
There will be more air to come out.
Sitting overnight with pressure on the brakes makes any air left easily bleed out.
Done.
Excellent info there Six, there are multiple reasons for air entering the system, the hose would be unusual to say the least, new one on me. I've learnt something new today!
 
Just an fyi, I had a Bking(hydraulic clutch, same as Busa), and the clutch would not stay bled.
Air was definately getting in somewhere.
After searching to no end, finding nothing, I replaced the clutch line...problem solved.
The brake/clutch lines are multi-layered, and it IS possible for them to have a small enough hole in one of the layers that lets air in, but also doesn't let fluid out.
I had a hard time beliving that until the line replacement proved it.
I had rebuilt the MC first as well, which is usually the first and best place to start.
Next I did the piston seal in the sprocket cover, and bled multiple times.
No change, until swapping the lines.

Also, on any brake/clutch line bleed, bleed them until they function normally. Then, pump the lever and zip-tie it around the handlebar(use cardboard around the grip and lever to prevent any damage).
Let it sit 12-24 hours, then bleed again.
There will be more air to come out.
Sitting overnight with pressure on the brakes makes any air left easily bleed out.
Done.
Kind of the same thing as the Zip tie mentioned above. I posted this one to thingiverse a while ago. If you have or know anyone with a 3d printer it's free.
https://www.thingiverse.com/thing:2419042
 
I don't think SS line brands matter too much. Galfer, Speigler, and I went with very expensive Goodrich Kevlar lines last time when I added the brembos. I did it mainly because the guys making the custom length lines here in town did the Kevlar. I can't tell a difference. Never had a problem with any SS line frankly. One cool thing about the Speigler lines is the banjos can be rotated and that can make installing them easier. Main thing is to toss those rubber lines!
 
I don't think SS line brands matter too much. Galfer, Speigler, and I went with very expensive Goodrich Kevlar lines last time when I added the brembos. I did it mainly because the guys making the custom length lines here in town did the Kevlar. I can't tell a difference. Never had a problem with any SS line frankly. One cool thing about the Speigler lines is the banjos can be rotated and that can make installing them easier. Main thing is to toss those rubber lines!

+1
I've had a few brands too, including Galfer and Spiegler.
Spiegler is the only brand I've seen with rotating banjos, and I really like that.
If you want the lines to bend and curve at just the right angle and look(for You personally), then being able to rotate them is a must(makes a big difference to picky folks, once you've used them, lol).
Spiegler has excellent quality and great customer service as well.
 
I may go Spiegler then because im picky about looks. I assume everyone ditches the crossover line from one caliper to the other and runs dual lines off the master cylinder, correct? From the sounds of it i should have my basis covered with new lines and master cylinder rebuild. If that doesnt fix it ill rebuild calipers last.
 
I also don't think cross over lines or 2 lines matters with a stock MC. With stock calipers and MC that's where you are losing feel, not the line configuration. If you upgrade the MC you might be more worried about how you run the lines. However most pre cut SS line sets are going to come as 2 lines to the front calipers. I think this is more a style thing to look like MotoGP bikes, but I could be wrong.
 
I may go Spiegler then because im picky about looks. I assume everyone ditches the crossover line from one caliper to the other and runs dual lines off the master cylinder, correct? From the sounds of it i should have my basis covered with new lines and master cylinder rebuild. If that doesnt fix it ill rebuild calipers last.
It never seems to stop, (no pun intended) I can tell you that much. :D
 
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