Yamaha 135LC

 Yamaha 135LC Specification
Yamaha T135[clarification needed] is an underbone motorcycle. It is also known as the Spark 135 in Thailand, Sniper in the Philippines, Jupiter MX in Indonesia, 135LC in Malaysia, Exciter in Vietnam, and T 135 Crypton X in Greece. It is made by Yamaha Motor Company and powered by a liquid-cooled 134.4 cc (8.20 cu in) 4-stroke engine. This underbone is fit for circuit racing than its rival Honda Sonic 125 and the Suzuki Raider 150 and one of the fastest 4-stroke underbone in the South East Asia.
In 2008, the fuel-injected version of the Yamaha Spark 135 was launched for the Thailand market, making it the second underbone motorcycle using fuel injection after the Honda Wave 125i. There are 3 main Yamaha factories that assembles T135. These are Indonesia, Thailand and newest is Philippines

  • DiASil (die-cast aluminum cylinder) which has better heat conductance to dissipate excessive heat easily.[citation needed]
  • Lighter forged piston technology came from Yamaha R6[clarification needed]
  • Roller bearing rocker arms with less friction than typical rocker arms.[citation needed]
  • 4-valve water-cooled engine
  • Fuel injection (2008 Yamaha Spark 135i in Thailand only)
  • Carburetor with throttle position sensor and accelerator pump (other countries) - The T135 uses Mikuni VM22 carburetor equipped with throttle position sensor for more precise ignition timing, increasing the engine's efficiency, and also an accelerator pump for better acceleration and instant response during take-off.[citation needed]
  • Catalytic converter
  • Dual-piston front disc brake (Yamaha 135LC Extreme Spirit in Malaysia)
  • Cast sport rims with tubeless tires (standard for Malaysian models only)
Manufacturer Yamaha Motor Company
Also called Spark 135, Sniper, Jupiter MX, 135LC, Exciter, T 135 Crypton X
Parent company Yamaha
Production 2005–
Class Underbone
Engine 134.4 cc (8.20 cu in) Forward-inclined single cylinder SOHC 4-valve 4-stroke water-cooled, comp. 10.9:1
Bore / Stroke 54.0 × 58.7 mm (2.13 × 2.31 in)
Top speed 110–140 km/h (68–87 mph)[citation needed]
Power 8.45 kW (11.49 PS) @ 8,500 rpm[citation needed]
Torque 11.65 N·m (8.59 ft·lb) @ 5,500 rpm[citation needed]
Transmission 4-speed constant mesh, wet, multiple-disk clutch, and centrifugal automatic (optional manual clutch model is also available)[clarification needed]
Frame type Tubular steel, diamond underbone
Suspension Front: Telescopic fork
Rear: Monoshock swingarm
Brakes Front: Single-piston disc, (Dual-piston disc - 135LC Extreme Spirit Malaysian-spec models), Rear: drum
Wheelbase 1,245 mm (49.0 in)
Dimensions L 1,945 mm (76.6 in)
W 705 mm (27.8 in)
H 1,065 mm (41.9 in)
Seat height 770 mm (30 in)
Weight 103.0 kg (227 lb)[citation needed] (dry)
n/a (wet)
Fuel capacity 4.0 L (0.88 imp gal; 1.1 US gal)
Oil capacity 1.1 L (0.24 imp gal; 0.29 US gal)
Fuel consumption 30 km/l (85 mpg-imp; 71 mpg-US) - 40 km/l (110 mpg-imp; 94 mpg-US)

Four Stroke Engine How it run?

Today, internal combustion engines in cars, trucks, motorcycles, aircraft, construction machinery and many others, most commonly use a four-stroke cycle. The four strokes refer to intake, compression, combustion (power), and exhaust strokes that occur during two crankshaft rotations per working cycle of the gasoline engine and diesel engine.
The cycle begins at Top Dead Center (TDC), when the piston is farthest away from the axis of the crankshaft. A stroke refers to the full travel of the piston from Top Dead Center (TDC) to Bottom Dead Center (BDC). (See Dead centre.)
1. INTAKE stroke: On the intake or induction stroke of the piston , the piston descends from the top of the cylinder to the bottom of the cylinder, reducing the pressure inside the cylinder. A mixture of fuel and air is forced by atmospheric (or greater) pressure into the cylinder through the intake port. The intake valve(s) then close.
2. COMPRESSION stroke: With both intake and exhaust valves closed, the piston returns to the top of the cylinder compressing the fuel-air mixture. This is known as the compression stroke.
3. POWER stroke.: While the piston is close to Top Dead Center, the compressed air–fuel mixture is ignited, usually by a spark plug (for a gasoline or Otto cycle engine) or by the heat and pressure of compression (for a diesel cycle or compression ignition engine). The resulting massive pressure from the combustion of the compressed fuel-air mixture drives the piston back down toward bottom dead center with tremendous force. This is known as the power stroke, which is the main source of the engine's torque and power.
4. EXHAUST stroke.: During the exhaust stroke, the piston once again returns to top dead center while the exhaust valve is open. This action evacuates the products of combustion from the cylinder by pushing the spent fuel-air mixture through the exhaust valve(s).

Body Modification

Exhaust for your LC

Head Modification

Using big valve means allowing for more air and fuel mixture to enter the combustion cylinder for more power delivered to the crankshaft. As usual, any modification that relates to increasing the power (hp) of the bike will increase the fuel usage.
This original Yamaha 135LC head is coated with copper. Why? This copper coating comes stock from the factory. It is used to make the slip much more heat resistant and also scratch resistant. When the valve got bigger the stock slip become much more thinner, so copper need to be adhered to the valve seat for protection against heat and scratch.

Engine Block Upgrade
Racing engine block is an oversize diameter of the piston and must be able to contain extreme heat and pressure inside it. This racing engine block for Yamaha LC135/Sniper/X1R is made from Taiwan. The durability of if is known and able to sustain long distance and endurance from the biker.
This racing engine block kit consist of engine block, piston, piston ring and piston pin.
There are two sizes available for the engine block that is 58.5mm and 60.0mm. The standard size of the Yamaha LC135 engine block is 54mm.
Oversize block gives more fuel to burn inside the combustion chamber, thus giving more power. Also, heat is generate more than standard condition with standard engine block. This one doesn't give any problem to the LC135 since it is liquid cooled.
Tuning of carburetor is also essential when you change the engine block. What is needed to be tuned is the main jet and pilot jet only. Standard main jet for Yamaha LC135 is 105 and pilot jet 20.0. So, what you need to do is to change that main jet and pilot jet to a bigger size. Main jet upgrade size is available in 110, 115, 120 and 125. Changing to the maximum size is not always the best idea. Try 110 first, then upgrade to larger size until you get a good speed all around and smooth running engine. If not, your carb is going to be too rich or too lean with fuel. Pilot jet upgrade comes in size 22.5 and 25.0. Also, try the small one first until you get the best mix. Tuning carb is essential to get the most efficient fuel delivery to the engine block combustion chamber.
After that, you also need to change your exhaust to high performance exhaust to get a better airflow of the exhaust gas. AHM, YY Pang etc is a good exhaust to choose from.

 Disc Brake

Yamaha LC135 Malaysian version doesn’t have rear disc brake. In Thailand, where the model of LC135 is known as X1R, Yamaha has put rear disc brake as standard and this make LC135 bikers in Malaysia drooling to have the rear disc brake installed to their bike.

No worry though, there is Yamaha LC135 Rear Disc Brake Conversion Kit available at your nearest workshop. If you can’t find it there, you can find it at NKS Sentul. This kit is complete with disc plate, caliper, bracket, pump and rim. For the installation of this kit, it is better for you to use the racing footrest since it is specially designed to fit well there. If you use standard footrest, you need to do a little bit of modification to the pump placement. If you still have trouble, just as your mechanic to do it for you.