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Matt Bleck
22nd September 2005, 13:53
A friend of mine has just brought a 99 CBR900RR.

I took it for a spin last nite and the forks feel like a pogo stick. Every time I'd go into a corner under braking (front brakes only) and let off the brakes it would spring back up.

Does this sound like to much rebound or not enough? And does anyone know which is the compresion adjustment and which is the rebound. We would consult the owners manual but he don't have one.

Any help would be very much appericated.

paul.....

Sparky Bills
22nd September 2005, 13:58
Are you just letting go of the front brake, or letting it off slowly??
It all matters. Pulling it on, and letting it out. ITS GOT TO BE SLOW AND SMOOTH!!

Sounds like too much rebound, how much dampening is there? May be too soft all round.
They have a 16" front wheel to,dont they? (depending on what year it is)

Marmoot
22nd September 2005, 17:35
It sounds like not enough rebound damping. Wind it a little bit into the H (hard) setting.

If it dips much under braking, put some compression damping on it (by winding the compression damping adjuster to H setting)

The rebound is on the top, and the compression is at the bottom of the leg.

He might want to change the fork oil as well. 99 is getting a bit far in history.

I used to own 99 Blade as well. A beauty and easy to ride fast, indeed. Your friend has made a good choice.

P.S.
Don't worry about the 16" wheels. It does not really make a problem at all.

P.P.S.
What's the rego number? Where did he buy it from? I sold mine but forgot to attach the owner manual with it. Could be mine.

HDTboy
22nd September 2005, 21:17
If you look at the bottom of this page there's a link called lts of manuals online. There may be something in there which helps.
Did you not go to the pub this thurs?

James Deuce
22nd September 2005, 21:20
I'm with Sparky B - too much rebound. Find the factory defaults in the handbook (or off the Internet) and then set the static sag to suit your mate's weight. Then take it for a ride. If the front feels harsh - too much compression damping. If it feels pogo like - too much rebound.

Also check the fork seals and make sure they're OK. There shouldn't be any fork oil on the sliders. If there is it's time for new seals, and the pogo effect might be no damping oil left in the forks.

slob
23rd September 2005, 19:06
[QUOTE=Jim2]I'm with Sparky B - too much rebound. Find the factory defaults in the handbook (or off the Internet) and then set the static sag to suit your mate's weight. Then take it for a ride. If the front feels harsh - too much compression damping. If it feels pogo like - too much rebound.[QUOTE]

Errr - No :hitcher: . The rebound damping mechanism is there to slow the forks down on the upstroke as the compression damping slows the forks on the downstroke.

More damping = slower fork movement. If the forks are rebounding (i.e. bouncing back) too quickly then you need to increase damping (i.e. turn adjuster to the 'Hard' setting) to slow them down.

Old thinned out fork oil could also be the problem here - best to have the forks reconditioned by a skilled mechanic.

Marmoot
23rd September 2005, 20:52
I think we got the term "rebound damping" and "rebound" mixed up here....