BORE UP JUPITER Z 2008 ,Serious pressure experienced by Yamaha when MP1 duck down in the class 125 cc 4 stroke tune up. Kinds of Jupiter-Z racing racer who is now strengthening Budi Ersan Diva Mart team, Boyolali Jateng dimanageri by Sutikno. To face the onslaught of Honda and Suzuki, Agus the tuner started to impose new methods in terms of picking machines.

The result of this research, Agus more focused on the use of valves that are plotted 28 mm (in) and 23 mm (ex). Valve size was 28 mm in the extreme, especially for the road race. Agus But this time reflect on the use of 54 mm piston crown Izumi who have higher. According to Agus comparative figures diameter piston valves with a diameter that is ideal. The resulting accumulation of vacuum cylinder 54 mm, it is believed more strongly compress the fresh gas which leads to the Keihin PWK 28 mm.

Karbu skepticism that has a design of this flat model makes sense for the supply of fresh gas is more concentrated offset the use of the valve head 28 mm. Indeed, the valve head 28 mm too short drain karbu mechanical rhythms, until finally the composition of suitable disposable main jet and pilot jet size: 140 32. Also the intake manifold also diremer 1.5 mm, while the exhaust manifold diremer 2.5 mm. Forwarded-Pang YY muffler with exhaust neck 28 mm and 32 mm Sarangan.

Excess valve 28 mm, in research Noken as not too dizzy. The problem with play duration at 275 degrees (in-ex), engine power can still be dikail gasingan short to medium to top speed. The rule must first valve springs replaced single model (single) Japanese products, with larger spiral but tenuous. "The good accuracy is more accurate back pressure valve so that the optimal effect of preventing the occurrence of floating," Budi convinced that actively researched.

Medium gasingan fixed underneath, should be seconded comparison lightweight gear ratio 1, ie, (35-12). Starting second gear intentionally made heavier (29-16), to support the purposes of rolling speed while devouring u-turn.

Special gear ratios concoction made Senggol market, the performance at top speed 4th gear ratio enhanced light (22-19). So as not too prolonged and weak at top speed. "After all, most stuck Senggol market straight 200 meters," Agus value.

Right calter sector provided 400 grams of fly wheel, with a diameter of 6 cm, but thick, as levers gasingan medium. Figures for 400 grams, according to Agus also not too heavy, so that it remains secure even if worn engine brake. Moderate coupling its dikanibal from Suzuki FR-80. For that the radius must digerinda clutch home again. And continued use of the clutch spring competition with higher dimension 3.5 mm.

CDI ignition devices apply Rextor Extreme combined with magnetic casing Vega and fulser Satria-F, and coil dihantar Yamaha YZ-125. "Ignition composition superior in terms of endurance, ignition currents in gasingan more stable medium," said Budi.

Piston: Izumi
CDI : Rextor Extreme
Koil : Yamaha YZ-125
Knalpot : YY-Pang
Katup : In (28 mm) dan ex (23 mm)
Fly wheel: 400 gram
Kampas kopling : Suzuki FR-80
Pegas katup: Jepang model single