Braking Question..what do you think

[tjpgi]

2009 ABS Concours with 12,000 miles.

Noticed yesterday with aggressive front braking felt a fair amount of vibration, no shaking or instability, in the front end. Just with slightly, and I mean slightly, less aggressive braking everything seemed normal. Rear brake, used alone, seems OK. In Hill country, just north of San Antonio it is difficult to find smooth asphalt on back roads, so at first I thought it was some vibration just from the road. I was able to find a short stretch of smooth asphalt and experienced the same thing. Without braking the front end seems quite solid, on sharp turns etc.

Could it be the pads, warped rotors, both or something else?

[Son of Pappy]

Shouldnt be bearings at 12k, but, it is easy to check.  Start easy, check for play in the head bearings, if that checks out, pull the front tire, use the axle and check for any play.  It's one of the two.

[VirginiaJim]

rotor(s)

[stevewfl]

rotor(s)

+1

agreed because they fail so often on the 08-09.  but can also be tire pressure, ever so slightly cupped tires, front suspension bad or not torque'd to specs, rim ever so slightly bent, etc

[sherob]

+1

agreed because they fail so often on the 08-09.  but can also be tire pressure, ever so slightly cupped tires, front suspension bad or not torque'd to specs, rim ever so slightly bent, etc

+2 rotors...

+1 the other stuffs...  worn Avon tires are great for head shake... 

[C1xRider]

If it's only happening under hard braking, then it's probably rotors.  However, someone posted a comment to this site not long ago about cleaning & freeing up the buttons that hold the rotor to the carrier, and fixed a similar problem.  Supposedly those buttons are supposed to float, and if they get jammed up because of road slime, it can cause what you're reporting.  Search around on this site, you should find the post and how he fixed his.

[tjpgi]

Thanks for the suggestions. I'll see if there is any road grime and clean it out. I need to schedule a visit to the dealer for the second recall on the rear master cylinder brake rod and will have them check the rotors and front end if there is still a problem. I have the extended warranty so if the rotors are warped they will honor it.

[pistole]

- use 10mm allen key. Turn all the bobbins which hold the rotors until they are free.

- this will probably sort you out.

.

[CARLÃO]

Sorry, I don`t agree with some of you. Agressive front braking means, as far as I know, that something very dangerous was about to happen. I believe it is impossible to have no vibration, shaking and instability when you need  to avoid an accidente, or when you are trying to save your life. When adrenaline enters your veins, front brakes!

[VirginiaJim]

I must be one of the few that use both brakes....

[Son of Pappy]

I must be one of the few that use both brakes....

Not really, there are those who have no choice
I use all three brakes.

[VirginiaJim]

 

[CARLÃO]

I also use front and rear brakes, when it is possible.

[VirginiaJim]

I don't think you have much of a choice, do you?  Both front and rear brakes are linked above 12mph, I think.  Please correct me if I'm wrong.  I'm not that up on the 10+ models. 

By the way, thanks for being here.  We appreciate having a multinational membership.

[CARLÃO]

Mr. Virginia, the integrated C14 ABS is not a perfect mechanism. Using only the front brakes, you add less than 75% of the potential of the rear. Using only the rear, you add less than 50% of the front. It is written at the manual. Actually, this is my first ABS bike and that`s why I am interested to the subject, And thanks,  considering me one multinational member, you make me very proud.

[tjpgi]

I use both brakes nearly 100% of the time ( use the back brake solo when entering a curve if I have exceeded my comfort level), a learned habit since driving bikes with either brake shoe stopping power or a single front caliper with a brake shoe at the rear. I was simply testing the brakes ( a controlled, alone on road stopping exercise) with aggressive braking when I started feeling the vibrations coming from the front end on my last ride. The front end seems stable as a rock with braking and cornering. Its just a feeling through the grips with the braking. I read many of the posts about cleaning the rotors, position of rotor in relation to the caliper, etc. and I'll try this and see what happens and then discuss the issue with the service dept at AlamoCycle Plex when I take the bike in for the recall.

Thanks to you guys for your ideas

[VirginiaJim]

So you are using both whether you want to or not it seems to me.  Kawasaki did not link the brakes on the 08/09 models on purpose.  They said that it would ruin the fun of the bike....  Sorry to all you guys with the 10s on up

http://www.kawasaki.com/Content/pdfs/products/concours_QandA.pdf

The above is very interesting reading if you haven't read it already.

By the way, you don't have to call me Mr. Virginia.  Jim is fine or Zathras or Robin....depending on my mood.

[TR34]

My bike is 09 as well. Around 9000 mil. At the odometer, I was having the same symptoms only when I use front brake slytly coming to a stop. Hard braking was fine. My dealer have replaced the rotors under warranty. Then, at around 15000 mil. Same thing, again new and improved rotors this time.

[TR34]

Forgot to mention, mine does not have an ABS .

[CARLÃO]

Very interesting the information, Jim, about the absence of link between the front an d rear brakes, but, at the brazilian manual, we can read, at page 130 that "The K-ACT helps to distribute correctly the braking force between the front and rear, in order to mantain a stable position of the bike. When  pressing the front brake lever, the front right and left calipers are accionated and, also the rear brake. When  pressing the brake pedal, the rear brake and the front right caliper are accionated. " In addition, we use one hand and one foot to brake, so, different forces are used to and it is very difficult to balance hand and foot to get 100% from both brakes. Also, at page 43, it talks about the distribution of the braking forces among front and rear whem the ABS 1 or 2 is in use. So, according to Kawasaki's brazilian manual, they are linked and called 1- Standard Mode and 2-Combined Improved Mode.