Just me being non mechanical minded and not understanding
I've since googled and now comprehend
:o
(28-07-14, 09:53 PM)unfazed link Wrote:Don't think it is a serious problem, mine was doing it since its first tyre change and still does it 84000miles later.
Balancing the front wheel improves it for a good while but it is always there. I remember years ago all fords cars had it at 40Mph and ford said it was harmonic resonance 
Since I do all my own work and know everything is ok it never bothers me.
90% of the 600 I have ridden do it.
Never was sure why one would want to take their hands off the bars while riding at any speed :eek
no way take my hands off at 100mph n not a twitch if it wobbles theres sumet not right ! find it sort it
waters wet, shit stinks !
Point appears to have been missed, it only appears to happen around 40mph, it does appear to happen above 50 or below 30. On any bike I have ridden including my own it has always been around the 40mph mark.
This issue has been around for years and frame design plus the harmonic resonance of the components involved can exacerbate it.
Watch the chatter problem in racing which is exacerbated by super stiff frames and is caused they think by harmonic resonance. Yamaha changed the stiffness of the frame in MotoGP to try and reduce the effect as changing the stiffness changed the point of harmonic resonance at a given speed
An unbalanced wheel can cause it and I do not mean unbalanced with a tyre on, but unbalanced bare wheel. :eek
Many standard wheels are out of balance by up to 30 grams from the factory due to manufacturing tolerances. :eek
On one particular fazer I checked, the imbalance of the bare wheel with discs attached was 5 grams. It did not have the problem. My original front wheel with discs attached was 25 grams out, but the new wheel replaced after an accident (insurers paid) was 12 grams out without the discs and was 14 grams out with the discs on and the problem is not as pronounced with this wheel.
Balancing wheels is not a perfect science as you cannot add weight to the exact point it is required. Unless you can get a machine to detect the inbalance of either side of the rim like the wider car wheels there will always be the shake possibility on the fazer.
A super quick steering bike is much more prone to the problem (which is why many race rep bikes with quick steering use a steering damper) and the 600 as a pretty quick steering bike it is more prone to it..
It is quite possible that those who have fitted a 120 section front tyre may not suffer from the problem as it slows the steering, I am surmising as I have never checked it.
I get it at any speed. starts off as a gentle wobble but leave it along and it gets into the resonance oscillation we call a slapper
anyway, been checked out and safe to ride
cant be that bad as two fingers gently on the right or left grip stops it.
I'm riding regardless now
Out of curosity, next time you change the front tyre ask the mechanic to check the wheel balance without the tyre and all balance weights off.
What tyres are you using? I found the sports tyres were worse than sports touring tyres as they sharpened the steering, but I prefer the sharper steering. It does not bother me, since there is no serious mechanical issue
Harmonic resonance of different materials.
