Good power and suspension, plus excellent handling, make t he KX 125 a ser ious contender once again this year.
Kawasaki didn 't fee l their upside-down forks were perfected yet, so the
U .S . models got 46mm standard uni t s which work exceptionally well .
By Nate Rauba
Photos by Kit Palmer and Rauba
awasaki 's KX125 was a good, allaround 125cc motocrosser last year.
Although it didn't have , anyone
distinguishing feature, all parts of the revamped
K
machine worked well to make
it a well -rounded package. It
had good power, handling and
suspension and, not to mention , carried Jeff Matiasevich to the
AMA 125cc West Coast Regional
Supercross titl e.
Wh en yo u 've got a winning formula. you often stick to it. And
Kawasaki has basically done just th at
with the '89 KX125, building o n last
year 's proven winne r with a few
improvements to keep it a head of th e
pac k.
Las t year's engine produced good
po wer fro m th e low end to th e upper
midran ge. After that it tended to sign
o rr a nd there was n 't much top end.
T o improve top end power this year
Kawasaki wid en ed, rai sed and modified the sha pe of the exha ust port.
T o match the new exha us t port the
diameter of the main exhaust valve
in Kawasaki's Integr at ed Pow ervalve
System !KIPS) has been en larged.
The main scavengin g port has also
been mod ified.
A redesigned combus tio n cha mber
also helps to wid en the powerb and.
A broader sq uish band reduces the
compression ratio from 8.39 to 7.8:1,
and the cylinder head gasket thickness has been red uced O.8mm to
O.2~m in order. to meet the new
cyh nde: ~ea? design,
.
ModlfrcatlO~S to th e expansion
ch am.ber also mcreases po~er , and
th e silencer h a~ been redesIgned. to
reduce th e norse level. A sea h ng
d.amper was adde d .be twee n the
SIlencer and exha ust pIpe to prevent
gas ~eakage.
, . .
LIke last year, a 35mm Keihin
PWK ca r b u re tor wi th cresce n tshaped sl i~e feeds the Elecro fusio npl ated cyh nder th rough case reed
valve s. Mor e air is su p p lied to the
~a rb ure to r through a ~ en larged
intak e boot from th e airbo x, Once
again ~wasaki us~s rotary valves on
both SIdes of the airbox that ca n be
opened for ex tra air intake or closed
for wet and muddy conditions.
A new digi ta l CDI unit provides
th e sp ark to ignite the gasses.
Clutch capacit y is in creased on the
'89 mod el by shor tening the height
of th e bosses o n' th e clutch wh eel
Imm , whi ch increases th e spri ng free
length. Leverage of the release lever
on the clutch cover is modified for
smoother engagement.
