Subject: Generator Bracket
Author: joe jump
Date: Oct 6, 2004, 7:09 AM
Post ID: 1717653307
What a timely discussion! Yesterday, riding to work, I noticed a strange
noise - a vibration that peaked in amplitude right around 4000 rpm. It
was big enough that I felt it through the foot pegs. Once I had arrived
at work, I put the bike on the centerstand and stood along side while
revving it up. The buzz I heard was the sheet metal v700 generator cover
vibrating onto the generator, but the vibration was the generator itself
bouncing at high frequency against the top of the engine case in the
saddle forward of the bracket. When I got home from work, I pulled the
front cover to see what I could see while the engine was being revved up
- I saw a loose fan belt doing all sorts of flailing around up there,
causing the tension to go all over the scale & setting up a vibration in
the generator, which led to the generator buzzing off the top of the
engine block. I've seen a few of these generators and they all have a
groove worn in them where they bear up against the saddle in the block-
mine was no exception!
Seems to me you want to avoid the condition where there is clearance
between the generator and the block in that saddle area, even with no
belt tension. It would be better to have the generator pulled down,
bearing tightly against the saddle by the generator bracket. It's the
loading & unloading of the bolts, flexing of the bracket that causes all
the problems with this interface. I opted for the shim method; a strip
of 16 gage steel sheet, cut about 1 inch wide with a 5/16 hole drilled
in the middle to allow the locating peg to protrude through.
All is well now. No buzz in the footpegs any more. It's like Motor New!
Joe in St Louis
850T powered Ambo
"Junkyard"