Running out of rebound front end chatter

[mark1]

took the old GPX250 to Ruapuna for a ride day(public NZD120 club NZD70 all bikes in together for 30 minutes every hour)The front started chattering on high speed corners.Apart from rebuilding front suspension I am thinking if I moved my body weight towards the rear this would lessen the load on the front?

[Wattie]

Is the front wheel balanced?
Rim straight?
Tyre good?

Try and work out why its doing it rather than hiding it in suspension.

[MadKaw]

After checking its straight as Wattie suggested - and most gpx's aren' - try heavier fork oil and 20 cents coins as preload adjusters.. I think we went 15 wt oil and 60 cents in each side on the wifes old GPX...

[mark1]

cheers guys
Wheel true and balanced,already running heavier oil.My next step is to replace the front tyre,Pirelli?

[Greenblood]

I am having the same problem with my track bike under brakes, I think it's the steering head bearings that are be the issue for me as everything else is OK....have you checked them?

[mark1]

Bearings appear to be ok ,will replace tyre and see this weekend

[ZX9R Man]

Race spec bikes have been known to suffer 'CHATTER' but i've never envisaged a humble GPX250 could cut it ??

[Gosling1]

Mark - I suffered a lot of front-end chatter on Billy's LC350 at the Island Classic a few years ago. One of the boys - thanks Steven Kairl - suggested I put a lot more weight over the front end......the chatter was all the way through Turn 2, which was a massive pain in the arse especially when trying to get on the gas for the run down to Stoner Corner...

putting more weight over the front definitely helped. We did not have the time or the stuff to be undertaking front-end rebuilds - so just made do with body positioning .