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My 1980 Vespa P200E
January
20, 2000 update
Mileage: 2600 miles
Well,
I seized up the trusty old girl while blasting down the freeway at about
75mph in late
October.
No big surprise- you have to expect that sort of thing with a hopped up
2 stroke.
I was
lane splitting down 101N in rush hour traffic, when the motor shut down
hard. It didn't
lock
up completely, but it was close. It was a bit exciting getting over to
the righthand break-
down
lane with no power across 4 lanes of heavy traffic that was moving at 35
mph or so
when
I was coming down from 75, but I made it. After stopping I whipped out
the tool bag
and
started wrenching away, eventually getting the bike to start via a push
after checking the
ignition,
plug, and other basic checks. It wouldn't idle and vibrated badly, but
she ran.
I went
on to work at a much slower pace, and drove the bike 10 miles home at the
end of the
day.
By massive adjustment of the idle screw I got the bike to idle, but the
vibration and lack
of power
remained.
I took
her in to see scooter-guru Barry Gwin at SF
Scooter Centre. Barry's mechanics tore
down
the top end and found a surprise- this bike had an old-school Penasco
213cc kit
installed,
not a Malossi! The cylinder was very scored, and the piston had bits of
the cylinder
embedded
in the skirt, as well as having the lower ring completely stuck to the
piston. It is
a testament
to the basic Vespa design that the bike would run at all- and the scary
part of that
is that
if you'd have ridden the bike, you'd have never know the bad state it was
in. It was still
faster
than a stock P200. While it's post-seizure performance was down on
power and vibration
was
high, that's compared to it's previous modified performance.
The previous
Penasco was a very mild kit with a Nikasil cylinder that can't be re-bored,
so it was
dumpster
food. Apparently I was getting such great performance from it do
to the skilled work
done
on my crank and cases by The Scooter
Shop. Penasco kits are unobtainable now, so we went
with
a Polini 210cc kit, which was expected to work well with my cut crank
and ported cases.
Barry
was right- the Polini worked great, in fact, combined with the cut
cases and crank, just
dropping
the Polini in would have created a monster fast race engine that would
have blown very
quickly
if used on the street. Initially the cylinder pressures were over
190 PSI, where they
should
be no more than 130 for a streetable engine! Barry's mechanics tried numerous
head and
gasket
combinations, eventually settling on a 200 Rally head with two Malossi
head gaskets,
which
lowered the pressure to 130, still fairly radical for a street engine.
This is why it is a
good
idea to let experienced techs kit your engine- you never know how previous
modifications
that
may have been done to your bike are going to add up. While I'd have been
more than able
to drop
the Polini kit on, I'd have never thought to check the cylinder pressure,
and while I may
have
had fun with the resulting grenade, it would have surely self-destructed
within a very short
time.
I'm now
going through a slow break-in on my new engine, and by all indications
it should be
much
more powerful than it was previously. I can't wait to get some miles
on it so I can wring
it out
and enjoy this kit as much as I did the last one.
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