7.5.8:
mobi`dahon`frame
6.11.25: trailer-trike# dahon`pivot
back to dahon like it was -- the way my dolly-trike project left it
. instead of nailing forks,
use the way it was connected at first:
. not only were the front forks riding on the back forks,
but also the handlebars made a connection to the seat post
-- this grabs the steering bearings from both sides,
and is much stronger than holding from the base alone .
steering`pivot`cap
7.1.19: mis"dahon has
trick part
. the dahon`handlebar`stem`collar has a crack?
that part is just a plastic cover to keep dirt out of the bearings,
and the reason it cracked is the same reason the bearings are loose:
. it has a shape that fits the nut above it;
if you don't align the two so they fit,
then you get a false tightening of the nut,
because the next time heavy pressure is applied,
the plastic cracks because it's bearing the pressure that should've
been applied to the nut .
. the steering joint is tightened and plastic grease cover taped back
on .
7.2.6:
. tried using the fuji`steering`pivot`cap to replace the dahon`s broken
one,
but the thread sizes
differ
so I had to repair the break instead .
mis:
. the last time I tried to tape the broken piece back on,
I didn't notice that I should tape it to the steering`s stator (the
frame) rather than the
rotor
(handlebar stem)
. added shim to stem for a better fit of the 10-speed`s stem inside the
dahon`s front.fork`tube .
handle`stem-seat`post
connection
6.11.29: dahon`stem
connection
. trouble finding dahon`stem (connects front.fork`trunk to handlebars);
it got totally disasm'd and mixed with another stem,
but it turns out that to drive the stem in full-depth,
the std 10-speed stem parts provide the best fit anyway
. notice how the stem is like a jaw with lips getting a forward bolt;
the stem is inserted with jaws facing seat`post;
the top jaw can be sawed off round to meet seat`post;
the bottom jaw still has a bolt hole to run cable ring
and this cable ring can be wrapped around the seat.tube-constricting
bolt .
7.1.13:
. the original dahon stem can't be found but alternative parts from the
10-speed work even better for my mod'
. the handlebar stem` head was tranformed for use as a seat`post support
by cutting a v-shape and making the 3rd cut by snapping it off .
7.2.11:
. added 5washers to each side of u-bolt used in
connecting seat`tube to handlebar`stem .
fork-fork connection
6.11.28:
. best general hack for adding front.fork along-side rear.fork
is
make a slot into rear bracket that is directed perp to load
or use just tiny bolts with some epoxy to keep forks together,
since most of the load bearing is done by the axle
6.11.29:
. after one of the forks tended to wriggle out of place,
I took apart the rear wheel to see how I could rearrange
the axle-nut-spacer assembly
. removing a spacer did allow the front.forks to fit on the rear axle;
but then it would not allow passage of the smallest sprocket
. rather than gouge the front.right.fork to make room for the sprocket,
I simply removed that sprocket by filing it`s teeth down to nubs
. I could have also widened the front.forks,
so that the right side of it would fit to the right of the
rear.forks;
but bending such a critical part
seemed impossible with the tools I have:
. not only was metal fatigue a concern,
but the job would make things unsymmetrical,
and would have complicated use of that fork`s brakes .
6.11.30: trials
as I looked into removing the chainwheel,
I vaguely recalled that if I just broke it off;
but, I had trouble disasm'ing the chainwheel to confirm that belief,
and since the whole point of this project
is enhancing my self-employability,
I decided against having a shop disassemble it .
. better to put the trailer-weighted front.forks both on the inside,
to minimize trailer-sized stresses on axle
. towards that,
another way to shift chain alignment
is to bend the rear fork`s heavy metal plate (not it`s tubing) .
7.1.23:
. drilled holes bolting forks together,
but after my naive application of usa hex stripped out a metric screw,
I decided to nix fastening the forks, and instead got the great idea
of simply bolting each fork separately to the axle;
ie, first bolt the wheel to the front forks,
then place the rear.forks on the remaining axle,
and use a 2nd set of bolts for them .
. to make the forks fit,
I file-reformed the rear.forks rather than the front.forks,
since in the mobi`design
the rear.forks bear only the pressures of pedal pushing,
whereas the front.forks hold up the weight of both driver and
trailer`boom (tongue.weight)
-- which can be quite heavy during
a hard stop .
. the extra set of nuts are also acting as spacers
that help keep the front and rear forks from
pushing harder against
eachother as the nut was tightened .
todo:
. a possible problem with front.fork` strength
is where it had been gouged for an easier fit along-side the rear.forks
assuming it would be nutted flat against and getting support from the
rear forks
. if it seems like additional strength is needed after slathering with
marine epoxy,
then there are clay-type epoxies that could fill available space .
. inspected fork mod's;
perhaps the gouged areas should be protected with epoxy? .
7.2.9:
left side front fork could use a thinner nut ?
(
find nut =>
. remove axle to pull stubborn nut,
found that the 3mm I wanted is connected to a shim anyway,
and the 2mm that I took as 2nd choice is too bent to be gentle on the
axle
threads?
find another one ? ok!
,
remove tire =>
remove (seat`post-stem connection, fender)
and loosen brakes
) .
7.2.11:
. checked to see if back forks are still well-seated: ok .
