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dentalprodigy

Spongy front brake???

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dentalprodigy
Hi everyone, 
                   Something's not right with my front brake lever feel.  The first 1/3rd travel doesn't do much, and I have really squeeze hard to get any stopping power.  It's not confidence inspiring and as a result I have to really plan my braking and it's starting to get dangerous.  I have some maintenance items on my to do list to hopefully resolve this but wanted some advice before I put the plans in motion.
 
My front brake was never this weak.  It was tight and had immediate positive feedback.  I bought the bike used with SS spiegler front brake lines and a 2008 GSXR600 radial master cylinder + EBC front brake pads which all resulted in stellar braking performance. 
 
After my highside in Oct '16, things have not been the same and I'm getting the feeling that they are progressively getting worse.  After the crash, my handlebar assembly was rotated a bit forward, rear brake lever was damaged and looking back on it... the front brake lever became very light/spongy/easy to press.  Could I have introduced air in the system then, or a leak ??  The master cylinder shows a level in between low and high.  I never really knew what it was before but I think it's normal.  I don't know how much I should add extra.  I know I'm not supposed to fill it right to the full line.  
 
Bike has ~11 k miles on it and the front pads are good.  
 
My initial gameplan;
- bleed brakes since it's been >2 yrs [manual says to bleed once every 2yrs]
I ordered a "Speed bleeder bag and hose kit" from Ebay and will get Dot 4 brake fluid from Walmart once it arrives to do the task.  Already got the official FZ-07 Service Manual aswell.
 
- I took a ziptie and held the front brake pulled overnight to see if it would improve things (it feels the same).
 
Anything else I'm missing.  
 
 

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mjh937
It sounds like you have a good game plan. I agree that you probably have some air in the system. Let us know your it works out.
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rick
With the bike (and master cyl.) on its side, it's a good bet air got in. 
 
Never been much of a believer in tying up the lever. You applied far more force while riding w/o that air bubble magically popping out the top. 
 
W/o opening the system, you can try a back bleed by pushing the pads inward one caliper at a time. An air bubble will be pushed bottom up into the reservoir. Don't do both calipers at once or you might overfill the reservoir and maybe make a mess. 
 
Your back brake fluid is the same age. Put new fluid in that one as well. 
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CarGuy7a
I had a similar issue on my CRF450R supermoto when I bought it used. The lever was really spongy and soft. Seeing as how I had no idea what had happened to the bike before my possession I just started checking things out and noticed the front brake was dragging severely and the pads were not returning correctly after pressurizing the brakes. So I took the calipers apart pulled the pistons out and cleaned them, cleaned and lubed all the slider pins, and installed new pads as the ones on it were toast. Drained the fluid and installed fresh and bled them and problem fixed.
 
You say that the brake lever was damaged. If you check everything out and still have the problem. You might want to look into the master cylinder to make sure there isn't any damaged seals from the hard shock that the lever took. Sounds like you are on the right track though to getting it fixed. Check the obvious first before digging deeper.
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peteinpa
When you bleed, do the left one first then remove the right, unhook the hose from the front fender, straighten that loop out, and bleed the right.
I think a lot of 07's have air in that loop over the fender.
 
Mine has never had mushy front brakes, must have been done right.

Got new red 2015 FZ-07 on 7/22/16!
Black 2006 Honda ST1300 53K miles.

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Guest ChicagoAJ
I like to take the calipers off and hang them by wire from the bars. The higher up you can get the calipers the easier it will be to get air to move through the lines and out the bleed screw. Make sure whatever DOT4 brake fluid you get is an entirely different color than the previous stuff so you know when your new fluid is mostly fresh.

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avanti
Given the stated sequence of events I think you may find that bleeding the brakes is not going to rectify the issue... hope it does, but I suspect (as others have noted) something is damaged and if not entirely causing the problem is probably aggravating it. Others have reported issues if there is the slightest misalignment of the m/c plunger and the lever assembly, for example. I would recommend disassembling and inspecting ANY suspect/known-damaged system after ANY lay-down... best of luck and do let us know what you find.

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dentalprodigy
UPDATE:
 
Just wanted to report back good news. Just bled the front and rear brake fluid and boy what a difference. I had forgotten how crazy strong and touchy the front brake had been on my bike. The difference after bleeding the front was night and day.
 
I used the “speed bleeder bag and hose kit" (eBay $9.99) and prestone dot 4 fluid (autozone $~5). First I bled the master cylinder, then left caliper, then right caliper. Old fluid was very dark. After this I test rode the bike and boy o boy does the front brake grab. Crazy strong stopping power. Then i came back and removed some more fluid from the master cylinder to keep the reservoir level under the full line. I read online not to overfill it so to be on safe side i kept it under the full line.
 
As suggested, I also bled the rear fluid. Didn't get to test ride after bleeding the rears because it started raining.
 
Very excited and relieved my spongy brake issue has been resolved. Thanks for the tips again everyone.
 
Pics are a little random and missing proper before and after shots but it was raining+ my first time doing this so I wanted to focus on the task at hand.
 
https://goo.gl/photos/6yYwsQiY3sWXhYwBA
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rick
Get in the habit of doing this every 2 years - 3 at the latest. Dot 3/4 brake fluid is very hygroscopic and sucks moisture from the air over time. This lowers the boiling point of the fluid and results in corrosion inside the calipers as well as other bad stuff.
 
with the air out of the system, it's a pretty easy job.
 
Just be careful to not get that fluid on plastic or paint - and if you do, rinse it off immediately with water. I go into those jobs assuming I'll spill and prepared to deal with it.
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