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62 

 

 

 

 

Trouble 

 

Location 

 

Remedy 

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fi

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 E

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C

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Empty fuel tank.  
 
Fuel tap off. 
Fuel filter above the-tap 
clogged. 
 
Chocked fuel pipe or screen in 
carburetter. 
 
Clogged  filler cap vent on the 
fuel tank. 

 
Transfer fuel reserve and re-
fuel at the earliest convenience. 
Turn fuel tap on. 
Unscrew the fuel tap and clean 
the filter. 
 
Remove  and blow the fuel 
pipe, remove and clean the 
carburetter. 
Clean filler cap vent. 

C

ar

b

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tt

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 c

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 b

fl

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Ir

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gu

la

sp

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rk

in

S

p

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rk

 a

le

a

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 e

n

d

 

 
Oiled sparking plug. 
 
Damaged plug insulation. 
Short circuiting between 
sparking plug points. 
Plug points gap too wide. 

 
Remove and clean sparking 
plug. 
Replace plug. 
Clean sparking plug. 
 
Adjust sparking plug gap to 
0.45 mm. (0.018 in.) 

N

sp

a

rk

 a

le

a

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 e

n

d

 

 
Ignition key not inserted. 

 
Insert the key. 

 
Dirty breaker points.  
 
Faulty breaker points. 
H. T. lead broken or loosed. 
 
 
 
Burnt lead insulation. 
 
Faulty condenser. . 
Damaged stator winding 
insulation. 
Water in contact breaker. 

 
Clean the point 

using a cloth 

soaked in petrol. 
Have point replaced. 
Tape insulation  crack, 
replace lead at the earliest 
convenience. 
 
Tape lead and replace at the 
earliest convenience. 
Replace condenser. 
Refer to a specialist workshop. 
 
Blow out water. wipe off 
carefully, allow to dry. 
 

R

eg

u

la

sp

a

rk

in

C

om

p

re

ss

io

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 p

o

or

 

 
Broken piston ring. 

 

Jammed piston ring. 

 

 
 
Sparking plug washer leaks. 

 
Replace ring. 
Remove, clean and replace 
ring. 
 
Replace washer. 

Summary of Contents for 353/04

Page 1: ...on and Operator s Manual WITH SPECIAL REFERENCE TO SERVICING AND ROUTINE MAINTENANCE OF MOTORCYCLES YEZDI 250 cc MODEL B JAWA 250 cc MODEL 353 04 Manufacturers IDEAL JAWA INDIA PRIVATE LTD MYSORE 570 002 SOUTH INDIA ...

Page 2: ...2 ...

Page 3: ...3 ...

Page 4: ...4 ...

Page 5: ...ront wheel 43 2 Removing the rear wheel 44 3 Removing the chaincase and the chain 45 4 Removing the rear chainwheel 45 5 Replacing the wheel ball bearings 45 6 Removing the cylinder head and barrel 49 7 Replacing the piston rings 50 8 Removing the carburettor 50 9 Dismantling the clutch 51 10 Dismantling the headlamp 51 11 Dismantling the steering head and fork legs 53 12 Handlebars twist grip 55 ...

Page 6: ...e 33 Fitting the piston rings 10 Lubrication chart L H side 34 Front fork sectional view 11 Lubrication chart R H side 35 Lubricating the steering head bearing balls 12 Draining the gearbox oil 36 Lubricating the steering head bearing balls 11 Removing the chain 37 Adjusting the twist grips connecting link 38 Removing the dual seat 14 Adjusting the brake 39 Disconnecting the rear suspension damper...

Page 7: ...spindle maximum load 214 kg Primary drive of 3 8 x 3 8 in chain 60 links Final driver by 1 2 x 5 16 in chain 120 links Primary and final drive ratios Primary 45 22 T Final 46 19 T Bottom gear 24 12 x 19 12 Second gear 20 16 x 19 12 Third gear 17 19 x 19 12 Top gear 1 1 direct Overall gear ratios Bottom gear 15 675 to 1 Third gear 9 800 to 1 Second gear 7 013 to 1 Top gear 4 952 to 1 Overall kickst...

Page 8: ...8 Fig 2 Engine 250 c c sectional view ...

Page 9: ...9 Fig 3 Plan of the Motorcycle ...

Page 10: ...nd lever fitted on L H side of the handlebars The gearbox is of the four speed type forming with the crankcase a monoblock engine unit The gear shifting is foot operated by means of a lever located on the L H side of the engine When changing gear the declutching is automatic Fig 4 Induction silencer sectional view 1 Induction silencer cover 5 Clamp 2 Air cleaner 6 Rubber sleeve 3 insert 7 Butterfl...

Page 11: ...y detachable the spindles being of the push out type The number of spokes is 36 in each wheel the spoke dia being 3 5 mm thread M4 The brakes are of full width hub and very efficient The fins along the brake drum circumference greatly facilitates in the transfer of heat resulting from braking and contributes to unchanged braking efficiency during continuous braking and on long runs The front brake...

Page 12: ...nsion The rear suspension operates on a circular path The pivoted rear fork is sprung by two cylindrical coil springs and fitted with hydraulic dampers The suspension dampers are protected by chromium plated steel covers The motorcycle could be locked by means of an ordinary pad lock A bracket has been located for this in the L H side of the steering head and the motorcycle could be locked after c...

Page 13: ...e stator Its position on the stator is located by the manufacturers by means of an Oscillograph to ensure most suitable tension for ignition and lighting and this position should never be altered under any circumstances The terminal base fitted on to the stator has the following terminal numbers Number 11 Voltage supply for Ignition 20 Voltage supply for battery charging 55 Voltage supply for Head...

Page 14: ...mo base plate 15 For ignition connected to terminal No 15 of H T Ignition coil 21 For battery charging connected to terminal No 21 of the rectifier 30 Connected to negative terminal of battery 30 Two leads from this terminal 1 to horn and 2 to stop light switch 55 For Head lights connected to terminal No 55 of magdynamo base plate 56 For Head lights connected to Dip switch on Handlebars 58 Two lea...

Page 15: ... other circuits are cut POSITION 3 Highway night riding Key fully inserted Ignition and charging circuits connoted the pilot light and Tait lamp are on The Head lamp main bulb is supplied with current from magdynamo direct To switch from main beam to dipped beam use dip switch on handle bars Battery gets charged at increased revolutions POSITION 4 Riding on battery Key fully inserted Ignition Coil...

Page 16: ...16 ...

Page 17: ...to the frame underneath the fuel tank The condenser of value 0 2 mF is placed on the frame in the vicinity of the ignition coil The condensor lead is connected to terminal No 1 of the ignition coil The sparking plug used either MICO HB W 175 Zi or KLG F70 The stop light switch is located in the R H side tool box Fig 6 Stop switch diagram All connections are of varnish coated automobile leads The l...

Page 18: ...e pointed out that the riding comfort on this type of motorcycle depends above all on the proper operation of the hydraulic dampers A new motorcycle just as a new motor car requires careful running if the engine is to attain a long life Only with such running in it is possible to harmonize the contact faces of all the moving parts smoothly so as to avoid local overheating of the friction faces and...

Page 19: ...60 km p h 37 m p h 75 km p h 47 m p h not limited 4th notch from top 3rd notch from top 3rd notch from top turn turn turn Note During the running 1n period the carburetters are set for a rather rich mixture It is necessary in the interest of fuel consumption to adjust the needle position and the pilot air screw in the course of running in accordance with the above table c When slowing down to a st...

Page 20: ...rning it anticlockwise Keep filler cap breathing hole clean After running in the motorcycle mix oil with fuel at a ratio of 1 to 20 at a ratio 1 to16 during the running in period Fig 7 Oil filling and inspection hole The fuel tank is fitted with a lever type fuel tap This fuel tap ensures an emergency fuel supply for about 20 km 12 miles depending on the terrain and speed Should this fuel reserve ...

Page 21: ...uretter air intake by turning the air cleaner strangler and flood the carburetter by pressing down the tickler pin Flooding and air intake closing should be carried out only if the engine is cold e insert ignition key into switch box d With a slight pressure of the foot on the face provided on the gear change lever hub press the lever towards the engine rotating it at the same time into the starti...

Page 22: ... gear with your left foot by pushing the foot gear change lever upwards and release the clutch lever slowly while at the same time gradually opening the throttle Should the clutch cable be broken the motorcycle can be started by slowly releasing the gear lever from the upper position As soon as a speed of 15 km 9 miles is reached close the throttle push down the gear lever with your foot engage se...

Page 23: ...ever into bottom gear and keep the clutch lever depressed When braking also use the front brake but a little later than the rear brake and only when travelling straight on Having finished riding turn off the fuel tap remove switch key and if required lock the safety lock Having finished riding for the day let the engine run at low revolutions after the fuel has been shut to consume the fuel in the...

Page 24: ...he carburetter headlamp and brakes clear of water Wipe dry enamelled and chromium plated parts and polish them with flannel or chamois leather The enamelled parts can be polished with an enamel polish To remove the water from the cylinder cooling fins start the engine the warmth of which will cause the water to evaporate Note Petrol paraffin and oil dissolve rubber tyres handlebar grips footrests ...

Page 25: ...oil after every 3 500 km 2 000 miles Change the oil preferably after having finished a trip while both the engine and oil are warm The warm oil will scavenge any accumulated sludge The correct oil level in the gearbox is determined by the inspection screw fig 7 bottom arrow Check the oil level from time to time by unscrewing this screw and top up if necessary Fig 11 Lubrication chart R H Side WARN...

Page 26: ...the oil rinse both the fork legs thoroughly with petrol make the suspension play several times drain the petrol and let it dry Having screwed in the drainplug 14 fill both fork legs with 175 c c of damper oil No more oil changes are needed except in case of dismantling the front fork or replacing a worn seal It is recommended to check after every 2 000 km 1 200 miles see Fig 34 The rear dampers As...

Page 27: ...s 6 15 2 1 Mobil Grease M P Heavy Grease Retinax A Wheel Bearing Grease Remove wheels clean repack bearings and refit 5000 Secondary Chain 10 1 Mobil Grease M P Graphite Grease Retinax A Multi Purpose Grease Remove wash in kerosene dry submerge in molten grease allow to set wipe surplus grease and refit a Brake cams b Control Cables 11 14 2 4 Mobil Oil BB G P 50 X 100 Motor Oil 50 Motor Oil 50 a 2...

Page 28: ...00 miles remove the R H side crankcase cover and with a few drops of oil lubricate the contact breaker arm pin Care has to be taken to ensure that no oil gets on to the contact breaker points The felt on the contact breaker base plate has to be soaked with grease The control cables clutch front and rear brake throttle should be lubricated after every 3 000 to 5 000 km 1 900 to 3 000 miles with a f...

Page 29: ...29 Fig 13 Removing the chain connecting link Fig 14 Adjusting the brake ...

Page 30: ...s on the inner tube air pressure in relation to the load carried As a rule the tyre has to be inflated so as to keep its original shape even under full load Running on under inflated tyres will result in the cover wall cord threads breaking Rim and tyre sectional view fitting the tyre cover The pressure in the front tyre should be 18 lb sq in 1 25 atm in the rear tyre 21 lb sq in 1 5 atm with pill...

Page 31: ... to the valve Using the tyre levers slip the cover edge over the rim edge Take care not to pinch the tube and thus damage it Having slipped all the cover circumference over the rim edge press the valve completely out of the rim base and remove the tube Having screwed in the valve core and inflated the tube partially the punctured spot will be best located by plunging tube into water Mark the punct...

Page 32: ...ever gradually on both sides towards the valve Proceed carefully in order not to damage the tube by pinching it between the cover and rim edges Tyre patching is an emergency remedy only during a trip when a nail has punctured the tyre For permanent repairs of tyres and tubes damaged by sharp gravel or glass rely on vulcanisation by a repair shop Fig 16 Correct tyre fitting ...

Page 33: ...n tightening these nuts so as to avoid damaging their threads Having adjusted the chain tension retighten the tensioning locknuts properly then the sleeve nut and finally the spindle securing nut Make sure that the wheels are in line Adjust the rear brake as well for having moved the rear wheel the brake might be slightly in constant operation and check the stop switch Check the chain tension ever...

Page 34: ...re accurately from time to time in the following manner a Screw the hand clutch adjusting screw on the handlebars slightly thus releasing the clutch lever b Clean with petrol or paraffin any dirt from the automatic clutch cam 6 and the clutch roller 5 c With your left hand take hold of the automatic clutch roller 5 and move it towards the cam and back d If there is any movement turn the automatic ...

Page 35: ...omatic clutch roller 5 Clutch control carrier 10 Automatic clutch cam 11 Cup 7 CARBURETTER The carburetter has been correctly set in the works The jet and the throttle valve have been selected by trail Therefore do not try to adjust the carburetter clean it only from time to time To start the engine easily the idling speed has to be set correctly This is done by the pilot air screw To obtain a poo...

Page 36: ...e idling speed of the engine with fully closed throttle can be adjusted by extending or shortening of the throttle cable and by securing the throttle valve by not letting it down to its bottom limit with the throttle valve screw oblique screw located on the carburetter body side This screw should never be Completely unscrewed To clean the carburetter dismantle it and wash the parts in clean petrol...

Page 37: ...t will prevent fine dust particles from passing through the filter and working its way into the engine and causing damage to the vital working parts Running on dusty roads makes more frequent cleaning of the metal air filter necessary preferably every 500 Km The air filter is accessible after freeing the two securing clips and the air cleaner top It is necessary to check from time to time the hole...

Page 38: ...8 MAINTENANCE OF ELECTRICAL EQUIPMENT Examine the leads from time to time and wind insulating tape round insulation cracks Damaged insulating can cause short circuits possibly entailing serious damage to the battery Clean the sparking plug periodically Carefully scrape off any carbon deposits set the contact gap to 0 45 mm 0 018 in by carefully bending the contact to the plug body The fuse is loca...

Page 39: ... km 120 miles and if necessary adjust the contact breaker point gap and ignition advance See para Ignition timing Fig 22 Removing the fuse Setting the Ignition Timing a Remove the sparking plug from cylinder and insert in the sparking plug hole or screw in the gauge indicator with thread M 14 x1 25 a special feeler gauge or a straight piece of wire b Find the T D C of the cylinder by rotating the ...

Page 40: ...t making the gap larger or to the right making the gap smaller g After setting re tighten the stator bolts Warning The contact breaker base plate should never be slackened or rotated in order to set the contact breaker gap Its position should never be altered under any circumstances Battery The maintenance is simple Maintain the electrolyte level it should be above the plates and separators in all...

Page 41: ...sted by tipping the reflector by means of the adjusting button in the top portion of the head lamp rim After releasing loosening the button push it forwards backwards as long as the headlamp beam is regulated Having correctly set up the headlamp beam tighten again the adjusting button 9 DECARBONISATION After the first 3000 km 2000 miles clean the exhaust silencer cores Clean again after every 5000...

Page 42: ...om piston ring grooves preferably with an old broken piston ring When replacing the piston rings fit the rings into the same grooves in which they were before being removed Having scraped off the carbon polish the parts in question and before reassembling wash them in clean petrol or paraffin Fig 23 Exhaust Silencer sectional view ...

Page 43: ... wheel When assembling after pushing home the spindle putting the spring washer into position it must not be forgotten and having placed the lock nut depress and release the front fork several times Only then tighten the lock nut and L H slider bottom end with the screw Check the suspension once more Fit the brake cable and adjust the brake so as to allow free rotation of the wheel Fig 24 Removing...

Page 44: ... to the right hand side Remove the brake reaction bracket on the L H side slide the wheel off the rubber blocks coupling of the chain wheel and inclining the motorcycle to one side remove the wheel To assemble the wheel reverse the above process The brake cable should be adjusted so as to allow free rotation of the wheel Fig 27 Rear wheel brake drum exploded view ...

Page 45: ...case Using the wire pull the other end of the chain through the rubber guide in the chaincase top half placed in position Slip the top end of the chain over the rear chainwheel and connect the two chainends with the connecting link and clip The open end of the spring clip should face the opposite direction of the chain rotation Insert the rubber seal between the top and bottom halves of the chainc...

Page 46: ...ngs the hub cover of the splined driver should be removed first Press in the new bearings by applying pressure to the outer bearing race using a piece of tube When replacing the rear chainwheel bearings proceed as follows Remove the back plate and push out the spacer Remove the seal bearing circlip and bearing from the L H side using a piece of tube Press on the new bearing using again preferably ...

Page 47: ...47 Fig 28 Rear wheel sectional view ...

Page 48: ...48 Fig 29 Front wheel sectional view ...

Page 49: ...ew the four nuts holding the cylinder head to the cylinder barrel and remove the cylinder head By means of the kickstarter bring the pistons into the B D C position and push the cylinder barrel upwards Note If it is difficult to remove the cylinder head lever it carefully by placing a screwdriver between the cylinder head and cylinder fin at the spot where the fins join After dismantling cover up ...

Page 50: ...trips Insert one strip under the piston ring in the middle and the two others under the piston ring ends To replace the piston rings proceed in the same manner 8 REMOVING THE CARBURETER a Disconnect the fuel pipe where it joins the fuel tank b Loosen the carburetter cover unscrewing the fastening nut off the mixing chamber c Remove the cover and slacken the flange fastening nuts d Push the carbure...

Page 51: ... clutch has five plates with cork inserts and four metal plates plus one pressure plate When reassembling insert first the plate with a cork insert which was under the pressure plate 10 DISMANTLING THE HEADLAMP The headlamp consists of three main parts rim with reflector bottom and top nacelle Remove the rim with reflector after unscrewing the securing screw M 5 from the rim bottom swing the rim u...

Page 52: ...52 ...

Page 53: ...t 41 and unscrewing the plug screws 32 Remove now the fork head lug and the bottom nacelle can be pushed out II DISMANTLING THE STEERING HEAD AND FORK LEGS Remove first the top nacelle handlebars unscrew the nuts 41 and 32 and release the fork head lug by tapping By using a special box spanner partly unscrew the nut holding the bearing cup In this manner it is possible to lubricate the top Fig 35 ...

Page 54: ... the fork legs and the steering head column To remove the front suspension dampers from fork legs unscrew the drain plug 14 Ref Fig 34 and top nut 1 after removal of top nacelle and pull out the entire damper unit from top of the fork tube 3 When refitting the damper unit into the fork tube ensure that the pin at the bottom of the end tube 15 is located correctly into the locating hole in the slid...

Page 55: ...er as well as an auxiliary tool box are located 15 REMOVING THE FUEL TANK Disconnect the fuel pipe and unscrew two screws M 8 x 10 securing the front clamp ears and the through bolt with nut 14 12 securing the rear clamp ears Do not forget to replace the three spring washers when reassembling 16 REMOVING THE TOOL AND BATUM BOXES AND COW LS The tool and battery boxes and cowls are held by three scr...

Page 56: ...it from its brackets in the frame and pivoted rear fork As compared to the former the new type damper has increased damping efficiency and is so designed that no topping up with oil is required It is recommended to have any possible repairs cleaning the interior etc done in a specialist workshop ...

Page 57: ...to be carried out Remove the cowls para 15 the suspension dampers para 16 The rear wheel pars 2 chaincase para 3 and the rear chain para 4 and exhaust silencers After removing these parts unscrew the bolt and nut on the tube bottom and the two nuts 17 on the L H side of the frame Push the released bolt out to the R H side and remove the thrust washer Using a puller pull out the fork pin It is reco...

Page 58: ...the nut 10 and pushing the washer off the earthing screw Pull down the securing strap and remove the battery Fig 41 Removing the battery 19 DISMANTLING THE SWITCH BOX Dismantle the switch box only if absolutely necessary Free and lift the headlamp reflector and remove the speedometer head After freeing the headlamp top nacelle the switch box located in it becomes accessible ...

Page 59: ...ignition setting is required Unscrew the two screws and remove the cover Before fitting the cover clean the seating faces off mud Tighten the securing screws evenly and check the cover front part to seat down properly in order to prevent the water leaking into the magneto space Remove the L H cover when it is necessary to dismantle the clutch to replace the clutch plates or the primary chain Proce...

Page 60: ...ent fuel supply Temporary short circuiting caused by faulty plug lead Weak mixture Improperly mixed petroil Clean the carburetter Open reserve supply tap pass fuel over re fuel inspect inlet manifolds Tape crack in insulation or replace lead Adjust carburetter Stir mixture properly before re fuelling Irregular sparking Unsuitable sparking plug Oiled sparking plug Excessive spark gap Dirty breaker ...

Page 61: ...encers Insufficient fuel feed Improperly set ignition Improper carburetter setting improper mixture Exhaust silencers clogged Worn cylinder interior and piston Engine drags wrong air crankcase halves or carburetter stump are not tight Remove cylinder head and barrel exhaust pipes and decarbonise Dismantle and clean fuel pipe Adjust breaker point gap and ignition advance Adjust idling peed needle p...

Page 62: ...ints Plug points gap too wide Remove and clean sparking plug Replace plug Clean sparking plug Adjust sparking plug gap to 0 45 mm 0 018 in No spark at lead end Ignition key not inserted Insert the key Dirty breaker points Faulty breaker points H T lead broken or loosed Burnt lead insulation Faulty condenser Damaged stator winding insulation Water in contact breaker Clean the point using a cloth so...

Page 63: ... carburetter to in the interior of the crankcase 2 PISTON MOVES DOWNWARDS After ignition of the mixture the actual working stroke of the piston begins transmitting the power of the expanding gases by means of the crankshaft mechanism and transmission to the motorcycle rear wheel The top edge of the piston opens first the exhaust port and the exhaust of the burnt gases takes place The top edge of t...

Page 64: ...64 Fig 42 Two stroke engine operation diagram ...

Page 65: ...65 Printed by PRINTOKRAFT Bombay 400 057 at The Book Centre Ltd Sion East Bombay 400 0022 20000 7 77 ...

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