Yet again I'm finding myself stumped by my not so humble k3. For the last 3 months or so my front brake has gotten more and more spongy. So finally after my bike got serviced I re built my font caliper and master cylinder. Only problem is nothing has changed. I'm at a total loss. From what I was able to measure everything was within spec. Any possible solutions?
Quote from: aussiegs on January 01, 2012, 04:32:49 AM
Yet again I'm finding myself stumped by my not so humble k3. For the last 3 months or so my front brake has gotten more and more spongy. So finally after my bike got serviced I re built my font caliper and master cylinder. Only problem is nothing has changed. I'm at a total loss. From what I was able to measure everything was within spec. Any possible solutions?
When you say "spongy" do you mean that when you squeeze the lever, if you don't squeeze it fast enough, you'll get all the way to the end of its travel with little/no braking?
One possible issue is water in your fluid. Does it seem like it gets better or worse after you've gone for a ride versus just letting it sit overnight?
Yeah the lever doesn't feel firm has little travel I'm not even game to take it out cause I know it won't pull me up. As for the diaphragm under the cap on the resiviour that could be it, it doesn't matter if it's on or off so maybe that.
But on second thought it should not matter because it's spongy either way. Just thought of that.
Quote from: aussiegs on January 01, 2012, 04:57:31 AM
Yeah the lever doesn't feel firm has little travel I'm not even game to take it out cause I know it won't pull me up. As for the diaphragm under the cap on the resiviour that could be it, it doesn't matter if it's on or off so maybe that.
But on second thought it should not matter because it's spongy either way. Just thought of that.
Well, if you haven't already, I would go ahead and flush the fluid and replace with new. That might fix your problem if it's old or has water in it. :)
Is the hose rubber or braided steel? If it's rubber, how old is it?
Most likely, just needs a good flush and new fluid like Kijona said.
Hose is rubber and original. From 03. And since I've only just re built the brakes of course the fluid has been replaced with fresh dot 4. And I've tapped on the fittings and caliper to make sure every drop of air is out. I've read the thread about hoses and this week I'm getting it replaced with a braided line but I'm doubtful it's gonna do much.
Quote from: aussiegs on January 01, 2012, 05:50:19 AM
Hose is rubber and original. From 03. And since I've only just re built the brakes of course the fluid has been replaced with fresh dot 4. And I've tapped on the fittings and caliper to make sure every drop of air is out. I've read the thread about hoses and this week I'm getting it replaced with a braided line but I'm doubtful it's gonna do much.
With such a simple device like hydraulic brakes...there isn't much that can be the source of the issue you are describing. What do you mean when you say "rebuilt" the master cylinder? It could be the little plunger that the brake lever pushes against...that's the only other thing I can think of.
So you've flushed and bled the brakes. That should rule out moisture and the fluid boiling.
Possible you still have air in the system. When bleeding I've found it necessary to give the brakes time to settle after bleeding and then re-bleed the next day to remove the last traces of air.
Although spongy, when you apply the brakes do they hold pressure? If they don't, then you have a leak. If they do, then something in the system has give to it. Either air in the system or the only other flexible component is the brake line, it's possible the brake line is ballooning or otherwise deteriorated. if it's an internal break down you may not see it. The Suzuki owners manual recommends the brake lines be replaced every 4 years.
When I re built it I put new seals on the plunger and measured it to make sure it was in spec. Inspected the bore to make sure it was ok (didn't have telescopic gauges to measure it ). And put new seals in the caliper and measured the pistons to make sure they were in spec (couldn't measure the bore cause no telescopic gauge due to the caliper setup). So the bores could be worn out I don't know. And yes bike has sat overnight and I've come back next day to have a crack at it and bled the line a little again but no bubbles. Something is not doing its job and there's not much to it I'm suspecting my bore of my master is gone because a month back when the sponginess was getting worse the break lever wasn't smooth it's was 'creaking' like seizing nearly I had to spray some inox on there to get it to smoothen up. But like I said the bore looked ok when I cleaned and inspected it but with no way to measure it yet I don't know.
Does the caliper slide freely on its pins?
Yep
A braided steel line will make a world of difference. Plus, brake lines are supposed to be replaced every 3 (or is it 5?) years. So if that's the original hose, you may have found the culprit.
When I bleed my brakes, I hang the master cylinder as high as possible with steel wire from the ceiling. That way it causes any air to naturally come up to the MC.
I find it weird that you need to replace your lines. In a car I've never had to replace them. But yes I can see your line of thinking.
Quote from: aussiegs on January 01, 2012, 06:47:32 PM
I find it weird that you need to replace your lines. In a car I've never had to replace them. But yes I can see your line of thinking.
Well, it all depends man, really. My 97 has original brake lines and the brakes are actually better than my 2007.
The steel lines will make braking much better, though I've found stock braking quite adequate for every day use. The reason is because the braided steel line will not "swell" under pressure like the rubber will. This translates into all of the "squeeze", or most of it anyway, being transferred to the brake calipers. :)
Good luck with it dude. You might need to replace a few parts but at least it's simple to fix. :)
Hey I totally get the reasoning behind braided lines, don't get me wrong but yeah looks like I'm up for component replacement here.
I think the problem is a lack of milk in the handlebars :thumb:
Michael
:thumb: :bowdown:
Quote from: mister on January 01, 2012, 11:01:27 PM
I think the problem is a lack of milk in the handlebars :thumb:
Michael
A lot of people never understand this theory. It's not just plain old 2% milk that is required, its evaporated milk. The dry white substance helps balance the handlebars, which in turn, keeps the brake fluid from vibrating too much and causing bubbles. Therefore making the brake spongy. :2guns:
Quote from: Kijona on January 01, 2012, 04:41:02 AM
When you say "spongy" do you mean that when you squeeze the lever, if you don't squeeze it fast enough, you'll get all the way to the end of its travel with little/no braking?
I could cry.....I really could :dunno_black:
Quote from: Dizzledan on January 02, 2012, 03:35:05 PM
Quote from: mister on January 01, 2012, 11:01:27 PM
I think the problem is a lack of milk in the handlebars :thumb:
Michael
A lot of people never understand this theory. It's not just plain old 2% milk that is required, its evaporated milk. The dry white substance helps balance the handlebars, which in turn, keeps the brake fluid from vibrating too much and causing bubbles. Therefore making the brake spongy. :2guns:
Damn and all this time I was using full cream :technical:
Quote from: Dizzledan on January 02, 2012, 03:35:05 PM
Quote from: mister on January 01, 2012, 11:01:27 PM
I think the problem is a lack of milk in the handlebars :thumb:
Michael
A lot of people never understand this theory. It's not just plain old 2% milk that is required, its evaporated milk.
NO! NEVER use powdered milk. We've established that over many indepth discussions here about the ideal handlebar milk. ANYTHING is better than powdered. BUT, of the liquid kind not all milks are equal. Search the forum and you'll find out everything you wanted to know about the correct milk to use. :thumb:
No Twisted.... don't fall for it. Avoid powdered.
@Sledge it's alright buddy (http://www.runemasterstudios.com/graemlins/images/hug.gif)
Michael
I'm a Paul's smarter milk man myself only 2% fat.
Quote from: sledge on January 02, 2012, 03:51:34 PM
Quote from: Kijona on January 01, 2012, 04:41:02 AM
When you say "spongy" do you mean that when you squeeze the lever, if you don't squeeze it fast enough, you'll get all the way to the end of its travel with little/no braking?
I could cry.....I really could :dunno_black:
So could I but I could see through the obvious errors on the post.
Quote from: sledge on January 02, 2012, 03:51:34 PM
Quote from: Kijona on January 01, 2012, 04:41:02 AM
When you say "spongy" do you mean that when you squeeze the lever, if you don't squeeze it fast enough, you'll get all the way to the end of its travel with little/no braking?
I could cry.....I really could :dunno_black:
You could cry? Are you trying to criticize me for something? If you are, then please be sure to PM me with any other criticisms you might have of me, or the way that I attempt to help others. ;) Otherwise, let's try actually helping the fellow.
Back to the topic at hand: AussieGS, if you don't mind, post your eventual solution here for others so if they run across a similar issue they'll know what to look for.
Quote from: Kijona on January 03, 2012, 12:37:17 AM
I wanted to make sure I was understanding his problem correctly. "Spongy" could mean different things to different people.
Especially if your name was Bob and your pants were square.
Quote from: adidasguy on January 03, 2012, 01:02:09 AM
Quote from: Kijona on January 03, 2012, 12:37:17 AM
I wanted to make sure I was understanding his problem correctly. "Spongy" could mean different things to different people.
Especially if your name was Bob and your pants were square.
:nono: You guys need to grow up. All I was trying to do was confirm what he was saying. Let's try to help the guy, okay? Isn't that what this board is about? Or has it become a platform for criticizing others?
Just to clarify spongy means what it says. It feels like when you squeeze a sponge except firmer.
Quote from: aussiegs on January 03, 2012, 01:42:44 AM
Just to clarify spongy means what it says. It feels like when you squeeze a sponge except firmer.
Had a friend say his clutch pedal in his truck felt "spongy". When you pressed it, it went all the way to the floor. Sometimes it's best to make sure that the person is using an accurate analogy.
Yep in this case it's the same.
Quote from: Kijona on January 01, 2012, 04:41:02 AM
When you say "spongy" do you mean that when you squeeze the lever, if you don't squeeze it fast enough, you'll get all the way to the end of its travel with little/no braking?
Ok....so back up what you say. Crack on at say 40mph, then AS SLOWLY AS POSSIBLE pull the front brake on and lets see if you can get the lever back to the bar WITHOUT going arse over tit.
Desite your very confident claim.........I say you wont manage but hey :dunno_black: ......be sure to get back to us when you have tried it :thumb:
Yes can and have done that after I put my new seals in the front brakes.
Quote from: sledge on January 03, 2012, 03:35:38 AM
Quote from: Kijona on January 01, 2012, 04:41:02 AM
When you say "spongy" do you mean that when you squeeze the lever, if you don't squeeze it fast enough, you'll get all the way to the end of its travel with little/no braking?
Ok....so back up what you say. Crack on at say 40mph, then AS SLOWLY AS POSSIBLE pull the front brake on and lets see if you can get the lever back to the bar WITHOUT going arse over tit.
Desite your very confident claim.........I say you wont manage but hey :dunno_black: ......be sure to get back to us when you have tried it :thumb:
First off, nobody ever said
anything about riding it. If it was HAVING that problem, I'd say stay off the damn thing until it's fixed.
Second, have you never had pleasure of trying to ride or drive something with hydraulic brake or clutch problems? A common symptom of hydraulic issues is if you squeeze/press too slowly, you'll reach the end of its mechanical actuation without much or
any feedback. The reason being is air or water inside the line. As you squeeze, the space, once taken up by air, is now being removed as it's compressed. I've heard this problem described as "spongy" by many people.
There is another common problem that happens, especially on
motorcycles, where the fluid gets kind of old or the cylinder starts going, the brakes will feel "mushy" at times. They still work properly, but sometimes it requires more force to squeeze the handle than normal. They also feel "dry" and unlubricated. This problem, as you can imagine, has ALSO been described as "SPONGY".
But I digress...
If you can find the time to be such a turd...surely you can find the time to post something useful here. ;)
Quote from: aussiegs on January 03, 2012, 03:41:16 AM
Yes can and have done that after I put my new seals in the front brakes.
I think you may need to replace the plunger in the master cylinder. If you're positive you don't have any leaks or air in the line, and you're sure that your lines are up to the task, you just need to replace the plunger assembly. It's obviously not doing its job.
Kijona?
Stick around for as long as I have and you will notice that every once in a while someone shows up in here who wants to be the center of attraction, has an answer for everything and at the same time believes everyone else knows nothing. I could give you several names/examples from the past but at this moment I think it fair to say the honour belongs to you :thumb:
I am not on a ego trip and nor do I feel I have something to prove but....this place is full of naive newbies who when looking for answers tend to forget about reason and instead listen only to whoever posts the most pics and/or shouts the loudest. I, like many of the other old-timers in here dont feel the need to or have the motivation to comment on a subject that has been covered 100s of times in the past...in fact I would love to see something new and original crop up in here as it very rarely seems to happen these days but if I read something I disagree with, particularly if I think its dangerous or misleading I might choose to say something....Thats the way it is, live with it :thumb:
But sledge how long since there was a spongy brake thread?
Ok update. Today I installed a stainless braided line with new washers. And there has been an improvement. But not much, the feel is firmer but not where it should be.
Ok quick question with no hose connected to it and with fluid in the reservoir if you 'pump' the master on its plunger should fluid shoot out?
Quote from: aussiegs on January 04, 2012, 07:10:01 AM
Ok quick question with no hose connected to it and with fluid in the reservoir if you 'pump' the master on its plunger should fluid shoot out?
Something should come out, either air or fluid. Hold a finger over the opening and feel for air being pushed out.
-Jessie
Did that and nothing. But no matter, I feel so effing stupid right now it's not funny. My neighbor was wrenching a trike across the road and we got to chatting and I told him my problem and he said clamp your line down and pump your brake to tell what's playing up. If you lever goes firm it's the caliper. If its spongy still it's your master. At this point I could have shot myself! So simple. So I did and low n behold my lever firmed up instantly. So I'm off to get another caliper seeing as new seals in the original haven't saved it. And yes I've tried a new bleed nipple too and no improvement. Thanks all for your help.
Helps not over until the problem is fixed...
Michael
are the piston seals on the caliper the factory item.if not get them and install with a small amount of vasolene on piston and in caliper groves.i once did a cheap job by not using factory o rings and had same trouble cause they wouldnt seal in caliper groove even though they wernt leaking and wernt getting air into system..my ten cents worth .
Yeah at this stage I'm giving anything a go to get it working. But the seals are genuine brand new.
Rightio update time. After acquiring an 05 caliper I'm 95% there just a bit of air in the system to bleed out.
Didn't we have this discussion a month ago... trying to bleed an air bubble from the bottom is fighting a battle as the oil moves down the bubble wants to do what bubbles do and float Up. Maybe burning1 mentioned it. I don't know :dunno_black:
Quote from: mister on January 08, 2012, 11:45:57 AM
Didn't we have this discussion a month ago... trying to bleed an air bubble from the bottom is fighting a battle as the oil moves down the bubble wants to do what bubbles do and float Up. Maybe burning1 mentioned it. I don't know :dunno_black:
A tool that understands physics: http://www.brakebleeder.com/products/brake-bleeders-1.html
-Jessie
I never saw that I don't think. Newhoo turns out my master cylinder kit from eBay was causing bypass and letting more air into my system. But with a genuine one in there now I'm 97% snd the lever feeks much better. So to recap. I've not got an 05 caliper, braided line and a rebuilt master cylinder.
Quote from: aussiegs on January 09, 2012, 12:00:40 AM
I never saw that I don't think. Newhoo turns out my master cylinder kit from eBay was causing bypass and letting more air into my system. But with a genuine one in there now I'm 97% snd the lever feeks much better. So to recap. I've not got an 05 caliper, braided line and a rebuilt master cylinder.
And has it fixed your problem?
Michael
Problemo fixed! :thumb: :woohoo:
Bit of an update on my brake, I still was not 100% happy with the feel of it compared with other bikes ive been trying out etc. So I went with a whole new setup for my front brake, the feel is solid yet progressive. Even when I 'grab' the brake the front doesnt lock (yes I know I shouldnt Im getting though this stage), and must say the new lever is very cool. Estimates are about 3 times more powerful than the original.
(http://a8.sphotos.ak.fbcdn.net/hphotos-ak-ash4/s320x320/401577_10150558179784879_533534878_8871576_1400700532_n.jpg)