kwolson2002 wrote:
> John -
>
> Yeah, I think it probably should have tilting wheels, unless you are trying to
reinvent a more complicated skateboard. That could be possible, too; the deck
tilts, but tilting only steers the wheels through a mechanism (at one or both
ends). You could either use an inclined king-pin setup, like a standard
skateboard (mountain boards come to mind), or some sort of tie-rod steering (I
haven't seen something like this, that I can recall). ...
>

> After reading Tony Foale on two-wheel steering motorcycles, however, I'm not
sure it is such a practical idea, even if it will "work" from a mechanical
standpoint.
>

it seems to be not very promising outside forklifts. I think the diwheel
dual powered rear wheels which steer by varying wheel speed ( Segway,
some lawn mowers, wheelchairs) is a better idea, but I haven't built
anything yet.

> Are you simply thinking the four-wheel board would be more stable/sure-footed?
...
>

Not exactly, I was thinking it would be easier for large, stiff old guys
like me to ride. But maybe a vertical handle like a kick scooter would
help, or maybe I am just not agile enough period. Speaking from POV of
the rider, not mechanically the dirtsurfer looks like it *feels* more or
less like a maneuverable skateboard, and I don't want to ride a
skateboard. Well actually I don't want to break my rear falling off a
skateboard. ;>)

also its an appealing project size, with small and inexpensive parts.

> One of the benefits of tilting is to be able to use light wheels on vehicles;
bicycle-type wheels just aren't very stiff WRT to loads applied parallel to the
axis of rotation,...For this reason alone, I'd think tilting would be the order
of the day for anything riding on light, bicycle-type wheels (but that's
sermonizing to the choristers, isn't it) - even four-wheeled dirtsurfers.
>

excellent point, this.

> I'd want tilting.
>

I need to look at the drawings again, but I was thinking of a Calleja
setup for the front and rear. Not sure its at all feasible for free
castoring. Its no more complex than other tilt mechanisms...


JF