Bars Judder 40-60mph

[superdaaan]

Hi guys,

I have a 98 CBR600 F3, had it for 4-5 months. Recently I noticed if I take my hands off the bars at around 50mph they shake quite a lot. Not enough for me to hit a tank slapper, but enough to worry about.

Anything below 40 and above 60 is fine? Suppose I should just drive everywhere at 70mph (i was being safe officer, honest)

Changed the wheel bearings, the head bearings had no play or notchiness. Wheel isn't buckled and rear suspension seems fine. Replaced rear tire, no cupping or wear on front so left that. Have stiffened up the pre-load - I'm out of ideas???

Many thanks in advance....
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[salem1987]

is the front tyre balanced ok? Thinking maybe one of the weights has fallen off and its totally out of balance.

[superdaaan]

Replaced the rear as there was a nail in it, got them to balance the front whilst I was there. Same issue
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[Islander]

Have you checked your tyre pressures?

[UrbanRacer]

Check the front tyre, make sure its on the rim properly.
Is the tyre old?
Do you have a front paddock stand? if so lift the front wheel off the ground and spin it and see if you can see any wobble or bulges.
Check the wheel itself and make sure its not cracked or anything like that.

do the same with the rear

[davebike]

Tyre pressure or uneven ware from low tyre pressure are the most common causes

Then wheel bearings and over tight head races and just faintly possible wheel balance

Start with the tyres pressure and how worn in less than 2mm tread left change
Good tyres = good ride
Worn tyres will always give poor handling and often wobbles
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[Skudd]

Having a top box can cause this as can having a knackered rear shock, but most bikes waggle a bit at a certain speed even if the window of speed is only 2-3mph
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[RodYork]

as others have said...9/10 faulty tyres...if its not that...then possibly head stock bearings...but a cheaper test to ensure you stay Coolio on't road isto check the tyre pressures/seating on't rim and tyre tread depth ( min 1mm over 3/4 of wheel)

work towards the problem..keeping cash firmly in't wallet!
( signed up Yorkshire man...with ferrets)
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[Vincent]

All above plus wheel alignment, don't rely on the chain adjuster markings without checking them first

You may know this but when it happens, don't grip the bars too tight....a common mistake.
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