Husaberg
Go Back   Husaberg Forum > Mechanical and Technical > Tech

Tech Mechanical and Technical for the rest of your motorcycle


Thanks Tree1Thanks
  • 1 Post By jon andersson
Reply
 
LinkBack Thread Tools Display Modes
July 9th, 2012, 12:43 PM   #1
Senior Member
 
Joined: Nov 2010
From: Salt Lake City, UT

Posts: 253
Thanks: 3

I Ride:
Brakes went soft after sitting for a few months

I have done a search and found similar posts, but nothing quite answers my question...

My 2010 FE450 brakes worked fine for the first 1.5 years. They worked fine in April. My bike then sat in the garage until July 4th. I then noticed that my front brake level pulled all the way in to the bar. I also noticed that my rear brake did essentially the same thing. Neither brake offered any stopping power. I tried pumping the brakes, with no change.

I then did a search and found people with similar problems, but I didn't like most of the responses given. Most people suggested the brake fluid had gone bad. I don't buy that theory. Even if it is "bad" or contaminated, it wouldn't suddenly become compressible. That just doesn't make sense.

Others suggested air in the line - but I don't buy that theory either. The symptoms are wrong. If I had air in the line I would expect pumping the brake to help, and I would expect the brakes to work, but then fade.

Oh, and there is not a leak - the reservoir was full to the brim.

CrazyTed posted a suggestion of tying the brake lever to the bar and letting it sit. So I tried it. I let it sit for about 1 hour while I went to the store to buy new fluid. When I got back, my front brake worked! It felt tight and it had stopping power. So, I tied it off and let it sit overnight. I wedged a board in place to hold the rear brake pedal down and let it sit.

After doing this magic overnight treatment, my brakes worked perfectly!

So, what I am now looking for is the explanation behind this.

Here is the best theory I have come up with...

With the brakes sitting unused, the master cylinder piston seals dry out. When I pull on the brake, the fluid leaks past the dry seals and I don't get any pressure. By 'parking' the piston in the 'brake on' position, it immerses the seal in fluid, which causes it to expand and once again work.

Is that theory valid?

If so, should the seals be replaced? Or will they be okay now that they are wet again?

If not, are there other theories?
DeeG is offline  
 
July 9th, 2012, 01:06 PM   #2
Junior Member
 
Joined: Nov 2011
From: Leicestershire

Posts: 13
Thanks: 0

I Ride:
Re: Brakes went soft after sitting for a few months

Haven't a clue about the theory but my front brake does the same if not used for a while. I solved the problem by leaving the bars turned to the left so the front brake lever is the highest part of the system. I've also had success by pulling the front brake lever in and then let it go/allow it to flick forward half a dozen times.
KTM's are renowned for doing it too so must be a brembo problem. Never had it on nissins etc.
Tonibe63 is offline  
July 9th, 2012, 02:33 PM   #3
Member
 
Joined: Apr 2012
From: Oklahoma

Posts: 34
Thanks: 0

I Ride: Husaberg FE570
Re: Brakes went soft after sitting for a few months

OK DeeG, first things first. Why in the heck did the bike sit unridden for 3-4 months? That's just wrong!

I've had to do the front brake thing on KTM's for years, never had to with the rear though. Folks claim by securing the lever, it forces any air in the system to the top. But being a sealed system, where does the air go if you don't bleed it Like you I can go from no brake to stoppies by zip tying the lever overnight.

It appears KTM might realize there is an issue that can be solved by doing this
http://www.calmoto.com/SHOP/KTM/61012016000.html
mikecarpenter is offline  
July 9th, 2012, 09:31 PM   #4
Senior Member
 
Joined: Nov 2010
From: Salt Lake City, UT

Posts: 253
Thanks: 3

I Ride:
Re: Brakes went soft after sitting for a few months

Originally Posted by mikecarpenter
OK DeeG, first things first. Why in the heck did the bike sit unridden for 3-4 months? That's just wrong!

I've had to do the front brake thing on KTM's for years, never had to with the rear though. Folks claim by securing the lever, it forces any air in the system to the top. But being a sealed system, where does the air go if you don't bleed it Like you I can go from no brake to stoppies by zip tying the lever overnight.

It appears KTM might realize there is an issue that can be solved by doing this
http://www.calmoto.com/SHOP/KTM/61012016000.html

I agree that having the bike sit is just plain wrong - it has been a very busy spring. I was about to remedy that with a 3-day trip last weekend, followed by several more outings. Unfortunately, my son broke his arm on day three, so that may set us back for several weeks.

Interesting KTM lever holder. Obviously, this is a common problem. But I guess I won't worry about replacing any parts or fluid.
DeeG is offline  
January 16th, 2016, 09:55 AM   #5
Member
 
Whosaberg's Avatar
 
Joined: Jan 2014
From: Nanaimo BC

Posts: 50
Thanks: 10

I Ride: Husaberg FE390
I have an FE390 and just discovered the same prob. Haven't ridden it for 2 months: almost no front brake. Reservoir full. Handlebars sat straight forward. Have tied a zap strap around the front brake lever. Will update with my findings.
Whosaberg is offline  
January 16th, 2016, 10:39 AM   #6
Senior Member
 
FE350's Avatar
 
Joined: Apr 2014
From: Chilliwack, BC, Canada

Posts: 528
Thanks: 176

I Ride: 2014 FE350, Beautiful Blonde
I had this happen on my KTM Brembo system.

I found that a little air was in the system. The brakes worked fine when used regularly but when it sat the air shifted and to the top it went causing the soft lever. Then pump it up and it was fine for a while.

Bleed the brake system completely and your off and running. Could have got a blurp of air from a fall ect.

Hope this helps
FE350 is offline  
January 16th, 2016, 01:07 PM   #7
Senior Member
 
Joined: Nov 2011
From: Nordic countries

Posts: 774
Thanks: 276

I Ride: Two FE570 -12
I had good front brake on my 570 until I slammed it hard in a crash. I guess some air came into the wrong place as it's been soft ever since. I have tried to bleed and fill using most methods, even replace the piston and rubber. It's better when I have it zip-tied and at a high position over night, and it is alright most of the time but not as good as new. I just tell myself I have a poor mans ABS....
Thanks from FE350
jon andersson is offline  
January 16th, 2016, 10:10 PM   #8
Senior Member
 
Huskyfatman's Avatar
 
Joined: Mar 2006
From: SO.NV.

Posts: 172
Thanks: 49

I Ride: Berg TE300, Guzzi Griso
Originally Posted by jon andersson View Post
I had good front brake on my 570 until I slammed it hard in a crash. I guess some air came into the wrong place as it's been soft ever since. I have tried to bleed and fill using most methods, even replace the piston and rubber. It's better when I have it zip-tied and at a high position over night, and it is alright most of the time but not as good as new. I just tell myself I have a poor mans ABS....
I've been using the overnight zip-tie method on spongy Brembos since the '90s. Always works works like a charm. Well except when I had a damaged caliper on my old ATK 605.
Huskyfatman is offline  
January 17th, 2016, 08:54 AM   #9
Member
 
Whosaberg's Avatar
 
Joined: Jan 2014
From: Nanaimo BC

Posts: 50
Thanks: 10

I Ride: Husaberg FE390
Well, the zip tie on the brake lever for several hours worked a treat. A few pumps after cutting the tie and she's rock hard. Going to bleed the system, service the calipers, and replace the pads today anyway and see if the crash-air in the system theory has any credence. With a 100 hrs since new, I doubt this has been done (I got her at 50 hours). She sat for 3 months over winter last year, and I don't remember this happening.
Whosaberg is offline  
Reply

  Husaberg Forum > Mechanical and Technical > Tech

Tags
brakes, months, sitting, soft



Search tags for this page
Click on a term to search for related topics.
Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Front Brakes Gone Soft - FE390 JohnnyQuest Wheels and Tires 6 May 20th, 2011 07:39 PM
sitting in the bath........ cypher Husaberg 11 July 22nd, 2008 08:45 PM
Button starting after18 months??? Grok Mechanical 10 April 10th, 2007 08:43 PM
loss of power gradually over last 6 months 44014 Tech 6 February 28th, 2007 01:12 AM
went riding for the first time in months dougn1 Mechanical 2 November 7th, 2005 05:13 PM


Facebook Twitter Google+ RSS Feed