Rear Chatter - Suspension Issue or Riding Style

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Rear Chatter - Suspension Issue or Riding Style

Postby bjn_42 » Tue Sep 02, 2014 12:30 pm

Hi Guys,

I had my suspension adjusted on my track bike recently and it made a huge improvement to the bikes stability. However there still appears to be a small amount of chatter coming from the rear. It only occurs when braking heavily (i.e. turn 3 at Queensland Raceway). I did notice that the chatter went away when i did not use the rear brake.

So is this issue suspension or riding style related?
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby Wattie » Tue Sep 02, 2014 12:55 pm

Locking the rear. It will be less if you feather the clutch a bit.
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby paulsj » Tue Sep 02, 2014 4:25 pm

Style. Slipping clutch a little or less engine brakes could work too, by braking then shifting and tip in. Have been working on both of these on my ZX9R to stop the same thing.
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby MadKaw » Tue Sep 02, 2014 7:13 pm

maybe increase the idle rpm too...
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby Jonnymac » Tue Sep 02, 2014 8:25 pm

MadKaw wrote:maybe increase the idle rpm too...

This ^
I wrote it earlier but for some reason it didn't post......
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby bjn_42 » Tue Sep 02, 2014 9:28 pm

I tried feathering the clutch and that worked really well but it doesnt seem to come naturally to me. I might try playing with the rebound a bit before I try anything else as it doesnt require me to change my riding style.
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby Wattie » Tue Sep 02, 2014 9:32 pm

Practice practice practice.
back before slipper clutches feathering was the only way
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby bjn_42 » Wed Sep 03, 2014 12:38 pm

Just did some research and found out the CBR doesnt have a slipper clutch however the ZX6R does. This may explain why it has never been a problem for me in the past.
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby Wattie » Wed Sep 03, 2014 4:37 pm

bjn_42 wrote:Just did some research and found out the CBR doesnt have a slipper clutch however the ZX6R does. This may explain why it has never been a problem for me in the past.


Doh!
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby paulsj » Mon Sep 08, 2014 8:04 pm

How high do guys turn the idle to reduce locking the rear under brakes I had mine at about 2700rpm which helped but made me cringe everytime clicking from neutral to first. Seemed to help but just rebuilt my calipers so hoping the stoppers are going to be working even better this time
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby MadKaw » Mon Sep 08, 2014 8:23 pm

I had the idle on my old zx9 race bike at about 2000 to 2200 rpm, It was fine and you could back it in a little on down shift. I also had the zx10r at about 2000 as the higher idle also makes getting on the gas a little smoother mid corner.. Not sure I'd go as high as 2700 though, but if it works, do it...... Maybe start in 2nd.. ;)
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby s man » Thu Sep 11, 2014 9:12 pm

My GSXR did the same thing when we went to superbike spec engine
Increase idle to 3000/3500 rpm,
Shaffer the rear pads, so you dont get as much bite,
Dont down shift to high in the rev range.
Fit slipper clutch.
Feather the clutch.
Dont use the rear brake until you get more experience.
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Re: Rear Chatter - Suspension Issue or Riding Style

Postby bjn_42 » Mon Sep 22, 2014 1:30 pm

Just as a conformation it was definitely a riding style issue. I tried changing down gears later in braking and that smoothed everything out. Took a few sessions to get used to but i had down pat by lunch time. Thanks for the information guys!
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