[net.cycle] Yamaha 650 that jiggles

mincher@umn-cs.UUCP (Richard Mincher) (08/19/84)

#N:umn-cs:4000001:000:529
umn-cs!mincher    Aug 18 19:22:00 1984

I have a Yamaha 650 Maxim which has had a tendency to shimmy if I let go of the
handlebars ever since I put the Fairing on it.  Recently it has been getting
worse, to the point where I have to hold on to the grips firmly to keep it from
jiggling, and the bike feels sqirmy going into tight corners.  

Does anyone know what causes this?  I think that the jiggling is at the same
frequency as the wheel revolution, but I'm not positive.

Please send responces to:  ihnp4!umn-cs!mincher

						 Thanks,
						       Paul Thompson

marauder@fluke.UUCP (Bill Landsborough) (08/24/84)

There are several reasons why this can happen... shocks, 
lack of a steering dampner, loose wheel spokes, etc. but
a couple you might seriously consider are:

*  The fairing is probably a handlebar mount and therefore
adds 25 or so pounds to the heaviness of your steering and 
then the shape of the fairing causes the wind to push it one
way.  Once it reacts to that push the shape of the fairing
has changed in relation to the wind and therefore pushes it
the other way.  This sets up an occellation back and forth
causing the wiggle.

*  This one actually happened to me on a race bike.  The front
tire was out of balance.  Not in the normal sense that you
think of balance where one END of the circle is heavier than
the other but that one SIDE was heavy then rotating around 
180 degrees the other SIDE was heavy! (hard to explain)
What it did was cause violent shaking, not bounce of the front
wheel. Talk about wierd.

Anyway, hope these and other inputs help.

Bill Landsborough