Editing Gilera CX125

{{Infobox Motorcycle
|name             = [[Gilera]] CX125
|image            = [[File:Gilera-CX125-91--4.jpg|frameless|Gilera CX125]]
|aka              = 
|manufacturer     = Gilera
|parent_company   =
|production       = 1991 -
|model_year       =
|predecessor      =
|successor        =
|class            =
|engine           = Two stroke, single cylinder, power valve
|bore_stroke      =
|compression      = 12.5:1
|top_speed        = 168.3 km/h / 104.5 mph
|power            =
|torque           =
|fuel_system      =
|ignition         = CDI
|spark_plug       =
|battery          =
|transmission     = 6 Speed
|frame            =
|suspension       =Front: 45mm Paioli forks, 100 [[wheel]] travel <br>
Rear: Single swinging arm
|brakes           =Front: Single 300mm disc <br>Rear: Single 240mm disc
|front_tire       = {{tire|120/60 -17}} 
|rear_tire   	  = {{tire|150/60 -17}} 
|rake_trail       =
|wheelbase        =
|length           =
|width            =
|height           =
|seat_height      =
|dry_weight       = 125.0 kg / 275 lbs
|wet_weight       =
|fuel_capacity    = 12 Litres / 3.17 US gal
|oil_capacity     =
|fuel_consumption =
|turning_radius   =
|related          =
|competition      =
}}

It could reach a top speed of 168.3 km/h / 104.5 mph.  

==Engine==
The engine was a Liquid cooled cooled Two stroke, single cylinder, power valve. The engine featured a 12.5:1 [[compression ratio]].  

==Chassis==
It came with a 120/60 -17 front [[tire]] and a 150/60 -17 rear tire. Stopping was achieved via Single 300mm disc in the front and a Single 240mm disc in the rear. The front suspension was a  45mm Paioli forks, 100 wheel travel while the rear was equipped with a Single swinging arm. The CX125 was fitted with a 12 Litres / 3.17 US gal fuel tank. The bike weighed just 125.0 kg / 275 lbs.  
== Photos ==
[[File:Gilera-CX125-91--4.jpg|600px|Gilera CX125]]
[[File:GIlera-CX125-91--2.jpg|600px|Gilera CX125]]
[[File:GIlera-CX125-91--5.jpg|600px|Gilera CX125]]
[[File:Gilera-CX125--91.jpg|600px|Gilera CX125]]
[[File:Gilera-CX1250002.jpg|600px|Gilera CX125]]
[[File:Gilera-CX1250003.jpg|600px|Gilera CX125]]
[[File:Gilera-CX1250001.jpg|600px|Gilera CX125]]
[[File:GIlera-CX125-91--1.jpg|600px|Gilera CX125]]

== Overview ==

Gilera CX 125














Gileras base is at Arcore,
near the famous Monza racetrack on the outskirts of the city, and appropriately
enough it was at the Milan Show that the local firm revealed their prototype CX
- a futuristic machine looking every bit as weird as any catwalk creation - back
in 1989. The CX was separated by a perspex screen from the prying public, most
of whom must have assumed it was destined for production around the year 2000,
if at all.

Late January 1991. The sun is finally sinking to end an unusually warm winter
day, and Im still sneaking glances at the CX125 to assure myself that this
surreal-looking motorcycle really is the bike Ive just been riding; a machine
that will be rolling off the Gilera production line and into hundreds of
showrooms by the time you read this
.
The idea still seems faintly ludicrous, like being able to buy a Versace
ballgown in a department store. But the CX is indisputably real, and although
you wont be able to buy it in Britain in the near future - supposed Gilera
importers Suzuki GB are barely aware of the bikes existence, so dont hold your
breath - then the masses in other countries across Europe certainly will.

The CX was designed by the Armani of the motorcycle world: Gileras chief
engineer Federico Martini, whose previous creations include the Bimota DB1,
perhaps the most beautifully styled bike of all time. Even the DB1 looks almost
normal in comparison with the striking CX, whose uniquely strange appearance is
capped by near-solid wheels which, from the right side, have no visible means of
support.

This is haute couture in cold metal and plastic, and unlike a fancy frock the
little CX has much more going for it than mere looks. The bikes dramatic
appearance has been shaped by its suspension design, which uses single-sided
arms and a single damper unit at each end. If the Bimota Tesi - which was first
developed when Martini was design chief at Rimini - is this years most
technically innovative motorcycle, then the CX is not far behind.




Nevertheless, if you strip
away the sculpted plastic and ignore the front suspension, the CX is improbably
conventional - if such a word can ever be used to describe the current crop of
state-of-the-art 125cc two-strokes. Its motor is this years version of Gileras
watercooled eighth- litre powerplant. Its identical to the unit used in this
years Crono race-replica ( follow-up to the SP02 tested last November ) except
for a revised exhaust pipe, which softens the power delivery slightly and
removes a couple of horses from the top-end.

That means an output of approximately 30bhp (the factory are a little coy about
revealing precise figures): enough to propel the typical Italian teenager to a
top speed of a shade over 100mph. Apart from the pipe, the major engine mod is
the adoption of an electronically operated exhaust power valve in place of the
previous mechanical system. The new unit sits behind a perspex cover on the
right of the engine, operated by a solenoid bolted to the rear subframe.

The main frame is a twin-spar job almost identical to the Cronos, made from
steel rather than the aluminum used by Gileras teeny-market 125cc rivals from
Aprilia and Cagiva. The frame contributes a mere 22lb to the CXs 264lb dry
weight, even so, and holds an single-sided alloy rear arm operating a vertical
shock.



But the front suspension is the vital part of the CX125, for it is unlike
anything seen before. A single alloy arm, of roughly similar dimensions to the
rear swing-arm, leads up from the front axle before curving above the top of the
mudguard. Attached to the arm is the suspension unit: a single upside-down
telescopic leg whose female section (the fork slider) sits just in front of the
steering head.

A series of articulated alloy rods connects the main arm to what is effectively
the bottom yoke, to operate the steering. The 17-inch front wheel, like the
similar-diameter rear, is a curved aluminum disc that from the right side looks
solid apart from a series of slots near its rim. It holds a single 300mm steel
brake disc, gripped by a twin- piston Grimeca caliper, and wears a low-profile
Michelin Hi-Sport radial tire.

Needless to say, the whole thing looks the absolute, Crufts-award-winning, dogs
gonads - and the benefits dont end with the strikingly clean styling that the
single-arm system allows. Gileras brochure trumpets a long list of CX ( What a
name to give a bike like this!) advantages over normal telescopic forks,
including not only increased rigidity and less weight, but also such things as
improved driving characteristics and the potential for enhanced aerodynamics.

Engineer Martini had been much more restrained at the prouduction bikes launch
at the Bologna Show last December, calling the CX a marketing bike, born by
commercial requests that worked in much the same way as normal forks. From a
technical point of view the weight is more or less the same and the rigidity is
more or less the same, so there is no great advantage or disadvantage, he had
said.



Such comparisons are difficult because the single-arm design, which has been
produced in collaboration with the Paioli suspension company, has yet to be
refined to the same degree. Gilera engineer Luca Bacchi has been responsible for
much of the development: When we began work two years ago the suspension unit
was much thicker, with a 60mm diameter, and the cast arm was also much thicker
than it is now, he said. But we made many calculations and fatigue tests and
concluded that this was too conservative, so we reduced the diameter to 45mm. Of
course, we will try to reduce it again in the future.

Bacchi claims the CX is very close to the Crono, which wears 40mm upside-down
forks, in front-end weight and rigidity. Perhaps the CX is a few grams lower,
and its stiffness against flex and also torsional stifness is a bit higher -
its hard to measure because this depends on the position of the linkage system.
If we wanted to save more weight we could design a special front wheel, or use
magnesium instead of aluminum.

As well as the improved ease of wheel removal, Bacchi mentioned a further asset
of the system. A conventional fork experiences twisting force when you steer
the bike at the beginning of a corner. The front wheel behaves like a flywheel,
and the gyroscopic force is great. On a normal fork this is transmitted through
the tubes and causes deformation, but on our system these forces are taken by
the linkages and are completely excluded from the suspension unit.



Careful design has ensured that the asymetrical CX front-end is evenly balanced,
with the single disc sitting neatly on the centre-line. Fitting the twin discs
required by a bigger bike would of course not be quite as easy. Bacchi quickly
replied that: In this case you would make a twin disc operated by a single
caliper, as has been used before on sports cars.

But he declined to say whether he already had such a set-up on the drawing
board.
Simply sitting astride the lightweight CX125 - the first machine off the
production line, I was told - was enough to assure me that a single disc would
be quite enough for the debut model. The diminutive bike looks as strange from
the pilots seat as its pointed profile does from the roadside.

The long, flat nose section ends in a narrow perspex strip that you can look
through if you crouch down behind the instrument panel (which includes a clock)
with your chin resting on the enormous round suspension cap poking through the
alloy top yoke.

In the absence of twin fork legs, the yoke is triangular only because it holds
the narrow handlebars. Theres plenty of steering lock; so much so that the tire
fouled the fairing slightly on full-turn. The footpegs are high and rearset, and
the thinly-padded seat completes a singleminded riding position. A touch of the
starter button produced a tinny two-stroke crackle just like that from any of
the similarly-appointed race-rep 125s.

And on the road the CX felt pretty much like its conventional brethren; so much
so that if I hadnt known its suspension was so unusual I probably wouldnt have
suspected a thing. The engine is the predictable unrestricted 125cc buzz-bomb,
though marginally less of an out-and-out racer than the likes of Cagivas Mito,
which has seven gears and needs several more unless youre quick-footed.

The Gilera stables nearly all its 30 ponies at the top- end, redlining at
12,000rpm and needing most of those revs if youre to make the most of it. The
power valve cuts in at just below eight grand, below which the acceleration is
as feeble the exhaust note is flat. But when you reach the magic point on the
tacho - which happens at 70mph if youre lazy enough to be dawdling in top gear
- the little motor opens its lungs, the sound changes from a drone to a harsh
shriek, and the CX picks up its skirt and heads for the horizon.



But handling is the CXs most important aspect, and the Gilera lived up to its
engineers claims. The suspension is fairly stiff (theres 100mm of travel at
the front, compared to the Cronos 130mm, for example) and the bike has a taut,
racy, flickable feel due in part to its light weight and racy rake and trial
figures. On the twisty country roads in the hills not far from Gileras factory
it could be thrown around with great ease and precision.



And despite that light weight and radical geometry, the CX proved impeccably
stable even on one fast, uneven fourth-gear curve that I repeatedly attacked as
fast as I dared for Goldmans lens. The harder I rode, the more planted and
secure the non-adjustable front felt; and the rear shock also behaved flawlessly
even on the couple of occasions that the sticky, 150-section Hi-Sport gave a
slight squirm to announce that it was close to the edge.

If there was a weakness, it was perhaps that the front felt a little solid when
hitting bumps in a corner. But Im not at all convinced that the Crono or a
similar small-bore sportster would have behaved any better. And there seems no
reason why a more sophisticated suspension unit, ideally with facility for
preload and damping adjustment, should not improve the CX ride still further.
Such an impressive first attempt shows massive potential.

Which raises the vital question of where Gilera go next with their design, and
whether it will appear soon with a decent-sized engine inside the slick plastic.
Martini will confirm only that he is definitely planning more machines with
single-arm suspension. Even if he obtains no performance advantage, he considers
a little extra cost (the CX sells for 6.3m lire in Italy, against the Cronos
6.2m) worthwhile for the styling freedom it brings.
But which engine to put in it? The factory are developing a big-bore V-twin,
with a V4 roadster also possible in a couple of years time. And for the more
immediate future, Gilera are rumoured to be working on a 680cc version of their
twin-cam 560 single engine, and to have produced a prototype road version of
their neat little alloy-framed single-cylinder racebike the Piuma.

Put the new engine in the Piuma frame, add CX-type suspension and style the
result in the way that only Martini can, and youd have a 60bhp, 300lb
streetbike that went like a rocket and looked like it had just arrived from
Pluto. The most exciting thing is that if Gilera wanted to, they could build one
next week. Its quite a prospect.



{|  class="wikitable"
|- 
!Make Model
|Gilera CX 125
|- 
!Year
|1991 -
|- 
!Engine Type
|Two stroke, single cylinder, power valve
|- 
!Displacement
|124 cc / 7.6 cu-in
|- 
!Bore X Stroke
|56 x 50..5 mm
|- 
!Cooling System
|Liquid cooled
|- 
!Compression
|12.5:1
|- 
!Induction
|32mm Dell'Orto VHSA32AS
|- 
!Ignition
|CDI
|- 
!Starting
|Electric
|- 
!Max Power
|29.3 hp / 21.8 kW @ 9900 rpm
|- 
!Max Torque
|18 Nm / 13.2 lb-ft @ 10250 rpm
|- 
!Transmission
|6 Speed
|- 
!Final Drive
|Chain
|- 
!Front Suspension
|45mm Paioli forks, 100 wheel travel
|- 
!Rear Suspension
|Single swinging arm
|- 
!Front Brakes
|Single 300mm disc
|- 
!Rear Brakes
|Single 240mm disc
|- 
!Front Tire
|120/60 -17
|- 
!Rear Tire
|150/60 -17
|- 
!Dry Weight
|125.0 kg / 275 lbs
|- 
!Fuel Capacity
|12 Litres / 3.17 US gal
|- 
!Consumption Average
|16.8 km/lit
|- 
!Braking 60 - 0 / 100 - 0
|13.0 m / 38.3 m
|- 
!Standing ¼ Mile
|14.8 sec / 142.5 km/h
|- 
!Top Speed
|168.3 km/h / 104.5 mph

|}

[[Category:Gilera motorcycles]]