Page 3
INTRODUCTION This manual was created by GAS GAS Motos, S.A. for the use of official GAS GAS services. It is principally directed at operators with a basic knowledge of the principles of mechanics and repair techniques. It contains precise instructions for making all the repairs, in addition to the necessary technical data to carry out the maintenance of the motorbikes.
Page 5
CONTENTS CONTENTS Sect. Sect. GENERAL INFORMATION GENERAL INFORMATION TABLE OF TECHNICAL DATA TABLE OF TECHNICAL DATA REMOVING THE ENGINE FROM THE CHASSIS REMOVING THE ENGINE FROM THE CHASSIS FITTING THE ENGINE ON THE CHASSIS FITTING THE ENGINE ON THE CHASSIS DISMOUNTING ENGINE DISMOUNTING ENGINE SERVICE AND REPAIR OF THE ENGINE COMPONENTS...
Page 6
- Avoid inhaling fumes from petrol or cleaning fluids, these can be highly toxic. Ensure that the work area is well-ventilated. Maintenance - Always use original GAS GAS spare parts and lubricants recommended by the manufacturer. Other spare parts may damage the engine. - Only use the tools specified for this vehicle.
Page 7
Engine serial number The engine serial number is stamped on the lower part of the left crankcase. Remember to quote the engine serial number each time you place an order for an original GAS GAS spare part for said engine.
Page 8
TABLE OF TECHNICAL DATA Engine Definition Mono-cylindrical 2-stroke engine, liquid-cooled, intake to crankcase Displacement in cubic centimetres 200 Engine: 199.4cc 250 Engine: 249.3cc 300 Engine: 294.7cc Fuel RON / SUPER-LEAD-FREE 95-98 octane. Mixed with SYNTHETIC 2T oil Mixture ratio 100% synthetic oil: petrol 50: oil 1 (2%) Petrol / oil semi-synthetic oil: petrol 40: oil 1 (2.5 %) Bore and stroke...
Page 9
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 REMOVING THE ENGINE FROM THE CHASSIS 01-01 Note: The cylinder head, the cylinder, the clutch and the ignition, can be removed without dismounting the engine from the chassis. - Thoroughly clean the motorcycle before starting to dismantle the engine.
Page 10
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 01-02 REMOVING THE ENGINE FROM THE CHASSIS Ed: 07/05 - Remove the whole exhaust system. Note: The oil must never be poured down the drain or into the environment. - Remove the drain plug -arrow- and drain the transmission oil.
Page 11
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 REMOVING THE ENGINE FROM THE CHASSIS 01-03 - Undo the screws -arrows-, remove the chain pinion and the hydraulic clutch calliper with the gasket. - Loosen the chain. - Extract the clutch rod -arrow- entirely.
Page 12
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 01-04 REMOVING THE ENGINE FROM THE CHASSIS Ed: 07/05 - Remove the screws -arrows- fastening the engine to the chassis. - Loosen the screw fastening the cylinder head support to the chassis.
Page 13
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 FITTING THE ENGINE ON THE CHASSIS 02-01 - Fit the engine on the chassis and correctly position on the supports. - Line up swing arm with the engine and chassis, grease swing arm and fit.
Page 14
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 02-02 FITTING THE ENGINE ON THE CHASSIS Ed: 07/05 - Place the chain pinion -2- on the secondary shaft and fit the circlip -1-. - Fit the clutch rod -arrow-. - Fit the hydraulic clutch calliper with a new gasket, fit the chain pinion guard and tighten screws -arrows-.
Page 15
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 FITTING THE ENGINE ON THE CHASSIS 02-03 - Remove the oil filler cap -arrow- and fill with new transmission oil. Viscosity: 10W30 Capacity 900 cc - Fit the oil filler cap with a new gasket and tighten.
Page 16
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 02-04 FITTING THE ENGINE ON THE CHASSIS Ed: 07/05 - Fit the kick-start pedal lever, apply Loctite 243 to the screw -arrow- and then tighten. - Tightening torque: 20 Nm - Fit the fuel tank and the vent hose.
Page 17
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 DISMOUNTING ENGINE 03-01 Prior instructions: Note: When dismounting the engine keep all the paired parts together. This includes gears, cylinders, pistons and other parts subject to natural wear in pairs.
Page 18
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 03-02 DISMOUNTING ENGINE Ed: 07/05 - Block the magnetic flywheel. - Remove the nut -1-. Warning: The magnetic flywheel nut is loosened by turning to the left! - Insert the extractor ref.
Page 19
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 DISMOUNTING ENGINE 03-03 - Block the turbine -1- of the water pump. - Undo the fastening screw -2- and remove the turbine from the water pump. - Remove the complete seal -arrow- from the water pump.
Page 20
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 03-04 DISMOUNTING ENGINE Ed: 07/05 - Remove the fastening nut -1- from the operating lever and the nut -2- from the exhaust valve rod. - Loosen screws -1- and remove thermostat cover. - Loosen cylinder head screws -2- in diagonal pairs and remove cover from cylinder.
Page 21
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 DISMOUNTING ENGINE 03-05 Note: There may be more than one gasket. - Mark the orientation of the piston towards the exhaust port using a permanent marker. - Place a clean cloth at the base of the cylinder to prevent the circlip from falling in the crankcase.
Page 22
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 03-06 DISMOUNTING ENGINE Ed: 07/05 - Open the safety catch -1- of the fastening nut of the clutch hub -2-. - Loosen the nut by holding the clutch hub. Warning: The clutch hub nut is loosened by turning to the left!
Page 23
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 DISMOUNTING ENGINE 03-07 Dismount the centrifugal operating system of the exhaust valve - Take the shaft and pinion off the water pump. - Undo the screws -arrows- and remove the support -1- from the exhaust valve control shaft.
Page 24
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 03-08 DISMOUNTING ENGINE Ed: 07/05 - Loosen the spring -arrow- of the gear lock using pliers. - Remove the screw -1- and take out the gear locking unit -2-.
Page 25
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 DISMOUNTING ENGINE 03-09 Removing the half crankcases - Undo the screws -arrows- fastening the half crankcases. - Turn the bench so that the left-hand half of the crankcase is facing upwards and remove the nut fastening the engine to the bench.
Page 26
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 03-10 DISMOUNTING ENGINE Ed: 07/05 - Remove the pinions of V and I gear -arrows-, the needle bearing and the adjustment washers. Removing the crankshaft - Remove the crankshaft unit -arrow- by pulling upwards. Note: If the crankshaft does not come off easily alternately tap the two shafts gently with a...
Page 27
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-01 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Crankshaft- Piston - Cylinder 1. Nylon counterweight 2. Nylon counterweight screws 3. Washer 4. Connecting rod piston pin 5.
Page 28
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-02 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Crankshaft Note: The crankshaft bearings must be completely replaced, for example, when replacing the outer piston the inner ring should also be replaced.
Page 29
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-03 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Connecting rod Note: The bearing of the connecting rod big-end is replaced together with the crankshaft journal, the connecting rod and the spacer washers.
Page 30
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-04 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Piston: opening at the end of the ring - Insert a piston ring in the cylinder, approximately 20 mm from the upper end.
Page 31
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Operation of the exhaust valve 1. Screw 19. Centrifugal spring aTightening torque: 6 Nm 20. Bearing plate 2.
Page 32
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-06 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Dismantling - Undo screws -1- and -11-. - Take out the bearings -2- using an extractor tool together with the washer -3- and the left-side exhaust valve -4-.
Page 33
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-07 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Valve control shaft support -32- - Check that the shaft of the centrifugal lever -31- moves freely within the support. Exhaust valve bearings -2- and -11- - Check that the exhaust valve bearings do not show signs of seizure or stiffness on turning.
Page 34
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-08 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Crankcase 1. Allen key 6x70 aTightening torque: 6 Nm 2. Left crankcase (outer side) 3. Cylinder studs 4.
Page 35
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-09 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Right half crankcase, inner side - Remove the centring bushings -1- and the centring pin of the selector spring -2-. - Before making any repairs to the right half crankcase, check the deformation to the same in the entire perimeter using a feeler gauge, both on the inside and the outside.
Page 36
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-10 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS - Remove the right crankcase bearings. Crankshaft bearing -1- - Remove the ball bearing from the crankshaft by pressing from the outside of the crankcase inwards.
Page 37
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-11 SERVICE AND REPAIR OF THE ENGINE COMPONENTS crankcase housing. Warning: Be careful when removing and fitting the needle bearings so as not to put too much pressure on the bearing housings.
Page 38
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-12 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Danger: When handling the crankcase after heating it, heat-resistant gloves should be used to protect hands. - Remove the right crankcase bearings. Centrifugal shaft bearing -1- - Remove the ball bearing from the centrifugal pinion using a bearing extractor (...
Page 39
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-13 SERVICE AND REPAIR OF THE ENGINE COMPONENTS - Fit the plate by applying thread-lock on the screws -5- Centring bushings -6- - Check the existence and condition of the centring bushings -6-.
Page 40
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-14 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Danger: When handling the crankcase after heating it, heat-resistant gloves should be used to protect hands. - Remove the left crankcase bearings. Crankshaft bearing -1- - Remove the ball bearing from the crankshaft using a bearing extractor (max.
Page 41
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-15 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Warning: Be careful when removing and fitting the needle bearings so as not to put too much pressure on the bearing housings.
Page 42
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-16 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Output shaft seal -2- - Fit the new crankshaft seal in the crankcase housing. The seal lip should face the outside of the crankcase. - Press down on the seal with a rod until it fits completely flat in the left crankcase housing.
Page 43
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-17 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Note: All gaskets, seals and O-rings should be replaced whenever the engine is dismounted partially or completely. - Place the clutch cover on a heating plate and heat to approximately 150 ºC.
Page 44
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-18 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Starter shaft seal -1- - Fit the new starter shaft seal in the clutch cover housing. The seal lip should face the outside of the clutch cover. - Press down on the seal with a rod until it fits completely in the clutch cover housing.
Page 45
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-19 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Clutch 17 18 1. Screw 6x20 24. Allen key 6x20 aTightening torque: 6 Nm aTightening torque: 6 Nm 2.
Page 46
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-20 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Clutch spring -26- - Check the condition of the springs and their length. Length of the springs Min.
Page 47
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-21 SERVICE AND REPAIR OF THE ENGINE COMPONENTS - Check the thickness of the iron clutch disc. Thickness of the clutch disc Limit: 1.45 to 1.55 mm Limit: 1.40 mm Clutch rod -7- - Check the clutch rod deformation.
Page 48
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-22 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Gearshift mechanism 1. Desmodromic bearing 2. Allen key 6x25x8.8 aTightening torque: 6 Nm 3. Flat washer 6x16x1.5 4.
Page 49
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-23 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Selector shaft -15- - Check that the selector shaft shows no signs of excessive wear or contact marks. - Check that the selector rod bushing -14- is in good condition and without excess play.
Page 50
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-24 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS - Check the play between the fork and its housing in the pinion. Play between the fork and. STD: 0.15 mm its housing in the pinion Limit: 0.25 mm...
Page 51
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-25 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Gears 16 14 21 10 1. Primary shaft 2. Needle bearing K25-29-10 3. Primary pinion V 4. Washer 25.2x31.5x1 5.
Page 52
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-26 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS - Check the contact surface of the bearings for seizure, signs of rolling and play. - Check the pinion teeth for wear or breakage. - Check the pinions and tracks are free of dirt.
Page 53
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-27 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Starter mechanism 1. Circlip D15 2. Washer 24x15.15x0.8 3. Interior starter pinion 4. Starter ratchet plate 5. Allen screws 5x15 aTightening torque: 6 Nm 6.
Page 54
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-28 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Starter shaft -11- - Check that the starter shaft teeth show no signs of excessive wear or contact marks. - Check the play of the shaft in the casing housing.
Page 55
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-29 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Reed valve 1. Allen screws 6x16 aTightening torque 6 Nm 2. Lower reed 3. Upper reed 4. Screws 5.
Page 56
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-30 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Reeds -2- and -3- - Check the reeds for cracks or splitting and for signs of ageing. - Check that the reeds sit firmly one on top of another and are dry.
Page 57
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 04-31 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Ignition 1. Ignition rubber top 2. Allen screw 5x20 aTightening torque: 6 Nm 3. Flat washer 5x12x1.5 4.
Page 58
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 04-32 Ed: 07/05 SERVICE AND REPAIR OF THE ENGINE COMPONENTS Ignition rubber top -1- - Check that the ignition rubber top is in good condition. Magnetic flywheel Kokusan -4- - Carry out the following tests using a multi-tester.
Page 59
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 ASSEMBLING THE ENGINE 05-01 Notes: All the engine parts must be perfectly clean and in optimum conditions for commencing assembly. Before assembly, apply engine oil to all the moving and sliding parts.
Page 60
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 05-02 ASSEMBLING THE ENGINE Ed: 07/05 - Carefully place together the gear cams of the primary -1- and secondary -2- shafts . - Place the pinion of 2 gear -1- and the adjustment washer -2- on the primary gear cam.
Page 61
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 ASSEMBLING THE ENGINE 05-03 Note: Remember to place the small gasket in the upper part of the crankcase -arrow-. - Place the screws in the position shown in the diagram. Screws -1-: 70 mm Screws -2-: 60 mm Screws -3-: 65 mm...
Page 62
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 05-04 ASSEMBLING THE ENGINE Ed: 07/05 - Lock the rotation of the crankshaft pinion and tighten the nut -arrow-. Tightening torque: 40 Nm Assembling the gear selector unit - Place the gear locking unit with the spring -arrow- slack and tighten the arrow -1 -.
Page 63
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 ASSEMBLING THE ENGINE 05-05 Assembling the starter pinion unit - Lubricate the housing of the starter shaft in the crankcase. - Insert the starter unit, ensuring that the ratchet is located between the plate and the casing.
Page 64
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 05-06 ASSEMBLING THE ENGINE Ed: 07/05 - Fit the clutch hub, the new lock washer and the fastening nut. - Hold the clutch hub down and tighten the fastening nut. Use thread lock.
Page 65
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 ASSEMBLING THE ENGINE 05-07 - Insert the pin through the piston and the bearing of the connecting rod small-end, and then fit the new circlip -arrow-.
Page 66
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 05-08 ASSEMBLING THE ENGINE Ed: 07/05 - Fit the right cover of the exhaust valve with a new gasket and tighten the screws -arrows-. Tightening torque: 8 Nm - Fit the left cover of the exhaust valve and tighten the screws -arrows-.
Page 67
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 ASSEMBLING THE ENGINE 05-09 - Position the turbine -1- of the water pump and fit the fastening screw -2-. - Block the rotation of the turbine and tighten the screw -2-. Use thread lock.
Page 68
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL 05-10 ASSEMBLING THE ENGINE Ed: 07/05 - Fit the ignition cover with a new gasket and tighten the screws -arrows-. - Fit the spark plug in the cylinder head. Warning: The spark plug should always be hand- threaded to the limit and then adjusted with a...
Page 69
Engine 200 cc / 250 cc / 300 cc EC ENDUCROSS WORKSHOP MANUAL Ed: 07/05 ELECTRICAL SCHEMAS 06-01...
Page 71
C/ Unicef, 17 - Polígon Industrial Torremirona - 1719 Salt (Girona) SPAIN TEL +34 902 47 62 54 / FAX + 34 902 47 61 60 w w w . g a s g a s m o t o s . e s PU010638016...
Need help?
Do you have a question about the EC 200 and is the answer not in the manual?
Questions and answers