Front brake took a break
 

Hey I looked around for this but didnt see anything. Went to take the bike out last week and when I grabbed the brake lever, nada, nothin. Wouldnt pump up, was like there was no fluid in it. Tried bleeding and still nothing.
Was thinking of getting a master cylinder rebuild kit but have considered using a different master cylider all together (RC51 or ?... thoughts?

Before you condemn it try keeping the brake lever tied back to the grip overnight, I have used this method when I bled brakes on my bikes and just didn't seem to get a a good feel out of the lever - it does help get trapped air out. If that doesn't work it sounds like you will need to rebuild it or use another model of master cylinder.

I dont think strapping the lever back will help this one.. it has no lever pressure at all, zero, it wouldnt even pump fluid out of the caliper when I tried to bleed it. Strangest thing Ive seen.

What I am wondering is if using a different master cylinder like from an RC would improve the feel of the lever? which one works best? does it bolt right up and use the same ss brake lines i have? Ive never been impressed with the oem unit on this bike from the start and that was 50k miles ago. Thanks.

The m/c rebuild kit is around $40! And with your mileage, it's probably a good idea to rebuild the calipers too. For that combined price, you can pick up an entire f4i system cheaper (with some luck) on ebay and upgrade.

http://cgi.ebay.com/ebaymotors/02-Ho...spagenameZWDVW

http://cgi.ebay.com/ebaymotors/HONDA...spagenameZWDVW

ok so i didnt look hard enough I just found the mod page with all kinds of good info... oops.

You really need to double check for leaks before you condemn the master cylinder. I've not heard of one going bad on the VTR yet. Soft, yes, but not completely shot as you describe.

About sometime around 2001 or so I was taking the ride out of my shed one chilly day. Grabbed the front brake lever and it got soft real quick. I discovered a leak at the master cylinder banjo. I went to tighten the bolt and just the act of putting the wrench on the bolt resulted in the pic below:

I will check again, the bike has been parked in the garage in the same spot for the last couple months, I found no leaks. I'll take it apart to investigate the cause. The brake has always been soft, tried ss lines, hh pads, multiple bleeds with different fluids. I have a TLR, couple dirt bikes and the SH brake has always been unimpressive. After reading the mod thread on upgrading the brake system it seems the way to go.

That pic is incredible, I'll take it apart to see but I bleed my brakes every spring.

I think it's MightyVac to the rescue. You have to drag the fluid through these systems to get them to pressurize.

TXSuperChicken and I did an overhaul on my clutch hydraulics this last weekend and it makes a huge difference in time spent to have the pump and a pal to help run the lever.

We had the system up to pressure with dot 3 in 15 minutes and had the dot 3 replaced with dot 5.1 in about another 5.

Dam Greg? Not even at the threads (stress corrosion in the thread roots can cause fractures). Looks like a SS dbl banjo overtorqued or residual stress fracture pop.

i had a rear banjo bolt do the same thing hawkrider. i hadn't tighted it in the 2 years i had the bike at the time and i noticed the rear was soft and was leaking, so i went to tighten it and it fell off

Well, this wasn't stainless or aluminum. Look at the color. Stainless should be more ductile too, with a larger grain structure, right? It looked like some kind of chromed brass or something. The fracture type was definitely brittle, not ductile. It was not overtorqued either. I truly think that the cause of the failure was brittle fracture due to temperature and low fracture toughness. There must have been a flaw somewhere in the metal that propagated due to increased tensile stress from the contraction of the material at low temperature. It was probably close to 0° at some point that week. The pic is old and I wish I could have taken better ones back then, but you can still see the stress concentration area in the bolt head.

Thanks,
I have my club meeting tonight so hope to take it apart tomorrow. I have a friend with a mighty vac and will try it, but the suggestion of upgrading the brakes to something all together better sounds good to me. :)

oh Ive na heard of the banjo bolt breaking like that either. Thats a new one too!

Sound likes engineer talk to me.......I didn't think they made banjo bolts out of brass?

HA! Funny. I am an engineer but just civil... not structural mechanics... This is the technical discussion page though. lol

I had one do that to me just a few months ago when I changed my master cyl. The thing just sheard at the point where the cross hole was drilled at and at a very low torque. It also appeared to be made out of brass. :shock:

+1 i'm a student mechanical engineer, makes since to me. i say upgrade the brakes. i love the gsxr 6 pots and master on mine

Did you have to change from the VTR brake lines? I have SS lines id like to keep. I can get new levers I guess... maybe sell these ones... carbon fiber painted ebay specials were only 30 or 35 bucks....

I thought at first it was chromed steel but the color threw me; its always hard to tell from a pic. Did you check it with a magnet to see if it was steel, wierd if its brass? Who made it? Temperature could be a factor but there had to be residual strees and/or a flaw to start with if torque is not a factor. I've have used aluminum banjo bolts but not brass? HEL will not use aluminum fittings on the hoses or bolts though Russell and others do (see http://www.helusa.com/HEL_Performanc..._Aluminium.htm).

Whatever, I hope it never happens to me somehow.

It was NOT ferrous. I checked, because when I saw the color of the material it piqued my curiosity. The part was an original Galfer part. They offered to send a new one after I sent them the pic. Needless to say I declined the offer. :roll: :noevil:

Interesting, these lines are Galfer. Now I really want to tear into it and see what going on, hope it doesnt sheer off too.

I have the same problem with my original front brake master cylinder, it doesn´t have any preasure, I tried bleeding and still nothing so I bought a rebuilt front master cylinder kit, about 30 euros, and a new banjo. Now I am using a f4i master cylinder but I prefer the original, so when I can, I will star to change the rebuilt kit into the cylinder, does anyone know where can I found more information about it? Thanks very much.

well at least im not the only one... when you took the banjo bolts off was there sludge?

Maybe it's a Galfer thing because now that you mention it, that's what mine was also, the one that came in the kit with the lines...

I´am sorry XLSR-VTR1 but my Engish is not very good and I don´t understand your question.
At first I was using a f4i master cylinder because my original one, was broken in an accident, so I bought another one and when I put it with a new banjo bolt, I bleeded the system and the master cylinder it had not any preausure, It was like the system didn´t have the dot 4 liquid, so I understood that the problem can be the wharf cylinder, that´s why I buy a rebuilt kit.

For what it's worth, I bought a brand new Nissin radial brake mastercylinder for my superchicken on E-Bay. It was a direct bolt-on application and is light years better than the stocker. I think that I still need some braided lines to go with it, but it was an huge improvement over stock. The only modification needed was a minor tweek to the resevoir mounting tab to make sure that the resevoir was properly situated. Even the stock brake line worked and bolted right up with no hassles.
The vender was awesome and had it shipped to me in just 3 days (their standard shipping through USPS).

Check here:
http://cgi.ebay.com/ebaymotors/ws/eB...2BSI%26otn%3D4

You said the lever was alwyas spongy?
I don't think you have a broken banjo bolt.
I think you had an air bubble in the brake line all along. the brake lever should feel firm when it's bled properly.

I would say you have an air bubble that finally burped into the master cylinder. That's good news, because it's easy to get rid of now.

there's an orifice that supplies brake fluid to the master cylinder from the reservoir. Take the M/C off and wire it up so the orifice is at the high spot, then press the slave pistons into the calipers. You should see the bubble come out of the orifice because the bubble floats.

Reassemble and pump the brakes back up, making sure you don't run out of fluid in the reservoir.

Somebody should ask Galfer why they make their bolts out of sintered macadamia nuts?

Ouch! I luv how the Buy IT NOW Price is $160 and the Starting Bid is $159.99

I'm a degreed mechanical. Has anyone ever tried Goodridge banjo bolts on the superhawks? I've had good experience with their lines and fittings on American V-Twins.