S
Steve Peake
Guest
On Mon, 10 May 2004 13:05:03 GMT, Simon Brooke wrote:
> in message <[email protected]>, Elisa Francesca
> Roselli ('[email protected]') wrote:
>
>> Behemoth doesn't like this at all. Just after I _stop_ nodding my
>> head, she decides to convey this subtle movement to the whole of her
>> frame, especially to her cranky, hypersensitive steering. And lo, the
>> handlebars start wiggling right out of control, left, right, left,
>> with barely enough space to compensate the imbalance because at the
>> same time I'm trying to slow.
>
> Dynamic steering wobbles are usually caused by too much lateral
> flexibility of the frame. They can be made worse by weight forward of
> the steering pivot (e.g. a heavy bar bag or bar-mounted basket). They
> are extremely dangerous - as you have found - and on the whole if it
> can't be traced to an unusual amount of weight forward of the steering
> pivot I would be inclined not ot ride that bike any more.
Also can be caused by the forks being bent backwards, creates the same
twitchy effect. Bent forwards does the opposite and make the steering do
very little.
Back in my Center Parcs bike shop days I was riding a trike back from a
villa, they have strange steering anyway, but this one also had forks about
25 degrees forwards, I knew I would be in the ditch many seconds before it
happened and even with the steering at about 45o over it didn't move from a
straight line!
Steve
> in message <[email protected]>, Elisa Francesca
> Roselli ('[email protected]') wrote:
>
>> Behemoth doesn't like this at all. Just after I _stop_ nodding my
>> head, she decides to convey this subtle movement to the whole of her
>> frame, especially to her cranky, hypersensitive steering. And lo, the
>> handlebars start wiggling right out of control, left, right, left,
>> with barely enough space to compensate the imbalance because at the
>> same time I'm trying to slow.
>
> Dynamic steering wobbles are usually caused by too much lateral
> flexibility of the frame. They can be made worse by weight forward of
> the steering pivot (e.g. a heavy bar bag or bar-mounted basket). They
> are extremely dangerous - as you have found - and on the whole if it
> can't be traced to an unusual amount of weight forward of the steering
> pivot I would be inclined not ot ride that bike any more.
Also can be caused by the forks being bent backwards, creates the same
twitchy effect. Bent forwards does the opposite and make the steering do
very little.
Back in my Center Parcs bike shop days I was riding a trike back from a
villa, they have strange steering anyway, but this one also had forks about
25 degrees forwards, I knew I would be in the ditch many seconds before it
happened and even with the steering at about 45o over it didn't move from a
straight line!
Steve