SERVICE Suzuki 250

SUZUKI 250CC MODELSTS250

MODEL TS250nDisplacement-cc 246Bore-MM 70Stroke-MM 64Oil-Fuel ratio Oil InjectionSpark plug

NGK B-7EElectrode gap-MM 0.6-0.7

Inch 0.024-0.028Ignition

Point gap-MM 0.3-0.4Inch 0.012-0.016

Timing-Degrees BTDC 21Electrical system voltage 6Battery terminal grounded NegativeTire size-Front 3.25 x 19Rear 4.00x18Tire pressure

Front-kg/cm^ 12Psi 17

Rear-kg/cm* 1.4Psi 20

Rear chain free play-MM 15-20 ^Inch %.% t

Rear chain size #525Number of speeds 5Weight (approx.)-kg 127

Pounds 280* A hreakerless electronic ignition system is used.Illustrations courtesy U.S. Suzuki Motor Corporation

TS250RTS250JTS250K

2467064

Oil InjectionB-7ES0.7-0.8

0.028-0.030

NA*NA*

24 (a 60006

Negative3.25x194.00x18

1.5211.826

15-20

#5255

111245

TM250JTM250K

2467064

Oil Iryection

B-8ES0.6-0.7

0.024-0.028

NA*NA*

21.5 ( 6000

3.66x214.00x18

1.0141.014

15-20

#5255

100220

MAINTENANCESPARK PLUG. Recommended

spark plug for normal use in modelswith contact breaker point ignition isNGK type B-7E or equivalent with anelectrode gap of 0.6-0.7MM (0.024-0.028 in.). Recommended spark plugfor TM 250 models is NGK type B-8ESor equivalent with an electrode gap of0.6-0.7MM (0.024-0.028 in.). TS 250models with P.E.I. (Pointless Elec-

tronic Ignition) are equipped with anNGK type B-7ES spark plug with anelectrode gap of 0.7-0.8MM (0.028-0.030 in.).

CARBURETOR. All models areequipped with Mikuni sliding valvecarburetors. TM 250 niodels are fittedwith 32MM carburetors and TS 250models use 28MM units. Refer to Fig.S12-1 and the following for standardcarburetor specifications:

U

Fig. S'l2-1'xptoled view oftypical Mikuni carburetor.Inset shows separatefloatffloat arm used on some

models.

1. Throttle cable adjuster2. Mixing chamber cap3. Throttle return spring4. Spring seat5. Jet needle clip6. Jet needle7. Throttle slide8. Needle jet9. Pilot air screw

10. Idle speed adjuster11. Float valve assembly12. Fuel passage13. Pilot jet14. Float arm15. Main jet16. Float17. Float chamber18. Float chamber drain plug19. Main jet holder20. Starter lever

15 19

TS 250 (VM 28 SC Spigot MountCarburetor)Main jet (15) #115Pilot jet (13) 25Jet needle (6) 5EP6Needle jet (8) P-2Throttle valve (7) 2.0Clip (5) in third groove from top ofneedle (6).TS 250 11 (VM 28 SC Spigot MountCarburetor)Main jet (15) #117.5Pilot jet (13) 25Jet needle (6) 5 DP 10Needle jet (8) P-0Throttle valve (7) 2.0Clip (5) in second groove from top ofneedle (6).TS 250 R, TS 250 J and TS 250 K(VM 28 SH Flange MountCarburetor)MainjetdS)

TS250R #170TS250JandTS250K #180

Pilot jet (13) 25Jet needle (6) 5 CN 3Needle jet (8) 0-4Throttle valve (7) 2.5Clip (5) in second groove from top ofneedle (6).TM 250 J Before engine #31406(VM 32 SC)Main jet (15) #260Pilot jet (13) 20Jet needle (6) 6 FJ 11Needle jet (8) Q-2Throttle valve (7) 2.0Clip (5) in third groove from top ofneedle (6).TM 250 J Engine #31406 and Laterand TM 250 K (VM 32 SC)Main jet (15) #230Pilot jet (13) 40Jet needle (6) 6 DP 1Needle jet (8) P-0Throttle valve (7) 1.5Clip (5) in second groove from top ofneedle (6).

Pilot air screw (9) should be 1-1^turns out from a lightly seated positionon SC type carburetors and 1% turnsout on SH type units. Float level shouldbe 28MM (1.1 inch) on units with onepiece float/float arm assembly. Levelon these units is measured from bottomof float with carburetor inverted togasket surface of mixing chamber bodywith gasket removed. Float level (AFig. S12-2) should be 23MM (0.90 inch)on TS 250 (VM 28 SC) units with sepa-rate floats and float arm. Float level (A

151

Suzuki 250 MOTORCYCLE

Fig. S12-3) should be 15MM (0.59inch) on TS 250 R, J and K (VM 28 SH)models and 9.IMM (0.358 in.) on TM250 (VM 32 SC) models. Level on allmodels is adjusted by bending tang (BFig. S12.2).

Fig. S12'2-'Float level on some eariy models ischecked by measuring from float arm to gasketsurface of float bowl with gasket removed. Ad-

just level by bending tang (B).

IGNITION AND ELECTRICAL. A6V 2 AH battery is common to allmodels equipped with lights. A recti-fier is fitted to convert AC current toDC. All electrical parts on PEI modelsare DC operated while earlier modelsuse DC current for hom, turn signalsand brake light only.

An ohmmeter or simple continuitytester may be used to inspect the recti-fier. When test leads are installed onrectifier, indicator should show conti-nuity in one direction and not in theother. If current flows in both direc-tions or not at all, unit is faulty.

IGNITION INSPECTION ANDADJUSTMENT OF CONTACTBREAKER MODELS. Inspect breakerpoints for burning or wear. Clean and

Fig. S12-3-Fioat ievei (A) on iater modeis ischecked by measuring from fioat arm to jetholder boss with mixing chamber body Inverted.

Fig. S12-5-Timing marks of TS 250 R and latermodeis. Use a power timing light and an engine

speed of $000 RPM to check PEi modeis.

TM

set maximum point gap to 0.3-0.4MM(0.012-0.016 in.). Ignition should occur(points just open) at 21 degrees BTDC.Piston will be 2.7MM (0.106 inch)BTDC and mark on flywheel will alignwith punch mark on crankcase at thistime. Timing marks are at approxi-mately same position as on PEI modelinFig.S12-5.

IGNITION INSPECTION ANDADJUSTMENT OF PEI (POINTLESSELECTRONIC IGNITION) MODELS.The breakerless electronic ignition sys-tems are used on TM 250 models andTS 250 R, J and K models. A small, in-ternal rotor is used on TM modelswhile TS models have a large extemalflywheel and coils to handle lighting aswell as ignition. After initial installa-tion, further adjustment should not benecessary, however, timing may beinspected with a power timing light.Timing marks (TMFig. S12-5 andS12-6) should align at 6000 RPM. Ifstator plate has been removed, timingmay be reset by installing stator baseplate with scribe mark at upper mountscrew hole (AFig. S12-6) alignedwith small boss, on crankcase. Rechecktiming with power timing light afterinstallation.

As the PEI magneto flywheel (Fig.Si2-7) tums, a current is induced inthe exciter coil (approximately 100-300V). This current is rectified by diode"A" and stored in the condenser (capac-itor). As the flywheel rotates a currentis also produced in the trigger coil. Thistrigger current is rectified by diode "B"and channeled through the triggersignal control circuit. The triggersignal is delayed in the control circuitby a Zener diode until sufficientvoltage is produced (depending on en-gine RPM) to release the trigger signalto the thyristor. When trigger voltageis introduced to the thyristor, currentin the condenser is released to the igni-tion coil and ignition spark follows.

Some parts of the system may be in-spected with an ohmmeter. Resistanceof the exciter coil (4Fig. S12-6 andS12-8) should be 320 ohms on TM 250models and 220 ohms on all othermodels. Exciter coil resistance is mea-sured between the black/red wire and

Fig. S12-6-View of P.E.i. magneto used on TM250 models. Refer to Fig. S12-8 for iegend.

Fig. S12-7'Slmplified dia-gram of PEi system used onthe TS 250 R and later

modeis.

Fig. SI 2'4-Checking point opening with a dialgage and static timing iight. Gage shown Is

avaiiabie from Centrai Tooi Co.

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SERVICE Suzuki 250

Fig. St2-B-Magneto assembly of PEt models.Center of screw (2) should be aligned with punch

marks on base plate (1).

Fig. S12-10-Dlfferent oil pump drives have been used. Early models have oil pump mounted on rightside of engine and drive from crankshaft. Later units mount oil pump at left rear of engine (right

view) and drive through kick idler gear.

1. Baseplate2. Screw3. Trigger coil

4. Exciter coil5. Lighting coii6. Flywheel

plate (1). Standard resistance of triggercoil (3) is 87 ohms on TM 250 modelsand 75 ohms on all other models.Trigger coil resistance is checked be-tween the red/white wire and baseplate. Standard resistance of primarywinding of ignition coil (measuredbetween black/white and white/bluewire) is approximately 0.7 ohms. Resis-tance of secondary winding (spark pluglead to ground) is approximately12,000 ohms.

The following checks are all made tothe PEI unit (located under seat) withan ohmmeter. Connect one lead fromohmmeter to black/yellow wire andother lead to black/white wire, reverseleads. Current should flow in one direc-tion and not in the other. Place leads onblack/red and black/yellow leads frombox. There should be continuity in onedirection and approximately 2 Meg-ohms resistance in other direction.Connect meter leads to black/whitewire and red/white wire. There should

A B

be no continuity in one direction and100-500 ohms in the other direction.Finally, connect leads to black/yellowand white/blue wires. Meter shouldbounce across scale and return to orig-inal position. If any of the previouschecks do not test as indicated, unitmust be renewed.

LUBRICATION. Oil capacity ofgearbox on TS 250 and TS 250 II isllOOcc. Oil capacity of gearbox on allother models is 700cc. Recommendedgearbox lubricant for all models is SAE20 W/40 motor oil.

Engine lubrication on all models isaccomplished by an automatic oil me-tering system. Only oils intended foruse in air cooled two cycle enginesshould be used. Oil is pumped in directrelation to engine speed and amount ofthrottle opening to the intake port andleft crankshaft main bearing. Trans-mission oil is used to lubricate rightmain bearing. On early models (TS 250and TS 250II) the oil pump is driven bythe primary gear and located on rightside of engine. Later units (TS 250 R, J,K and TM 250 models) mount oil pumpon left side of engine to the rear anddrive through the kickstarter. Adjust-ments on all models are similar.

Turn cable adjuster (CFig. S12-9)so that aligning marks (A&B) alignwith throttle wide open.

If oil pump has been removed or al-lowed to run dry, it will be necessary tobleed the injection system. Pump andmain inlet line are bled by looseningbleeder screw (D) and allowing oil toflow until air bubbles are no longerpresent in oil coming from bleeder hole.Air in pressure lines is expelled byholding oil pump control arm full onand running engine at idle until air isremoved.

CLUTCH CONTROLS. Clutch maybe adjusted on TS and early TM modelsafter removing adjustment cover onleft engine case. Loosen lock nut (18Fig. S12-12) and turn adjusting screw(17) until it just contacts push rod (14).Back adjusting screw out ^/^ turn andtighten lock nut. Turn adjusters onclutch control cable to obtain 4MM freeplay at pivot of clutch lever on handlegrip.

Clutch adjustment on TM 250 K isaccomplished by turning cable adjus-ters at either end of clutch cable to ob-tain free play of 4MM measured atpivot of handlebar mounted clutchlever.

Fig. S12'11-Clutch assemblyused on early model TS 250.Basic parts are similar to TS

250RunitlnFig.S12-12.

Fig. St2-9-O// pump adlustment and bleedpoints. Small punch marks on lever are factoryreference marks and should not be used as

aligning marks.

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Suzuki 250Fig. S12'12-Exptoded view ofTS 250 R clutch assembly.

Later units are similar.

1. Bolt2. Washer3. Oil seal4. Clutch spring5. Pressure plate6. Friction discs (6 used)7. Steel plates (6 used)8. Push piece9. Lock washer

10. Clutch hub11. Push rod12. Thrust washer13. Primary driven gear

assembly14. Push rod15. Oil seal16. Release screw

assembly17. Adjusting screw18. Lock nut19. Release screw return

spring

Fig. S12-14'View of clutchand release mechanismused on TM 250 K models.Clutch components are sim-

ilar to other models.

1. Release pinion2. Screw3. Oil seal4. Screw5. Arm6. Thrust washer7. Needle bearing8. Release rack9. Needle bearing

10, Spacer11. Dowel

MOTORCYCLE5 6

10

12

13

U

Fig. S12-15-Front suspension system used on TS250, TS 250 R and TS 250 J. Units used on other

TS models are similar.1. Steering stem head2. Fork inner tube cover3. Steering stem4. Fork top bolt5. "O"ring6. Spring guide7. Pinchbolt8. Fork spring

9. Dust cover10. Outer tube nutU. "O'ring12. Metal Blide13. Fork inner tube14. Fork outer tube15. Axle pinch bolt16. Oil drain plug

SUSPENSION. Front suspensionunits on early (TS 250 and TS 250 II)models contain 250cc of oil each andunits on later (TS 250 R, J and K)models contain 255cc of oil each. Frontsuspension units on TM 250 J and TM250 K models contain 190cc of lubri-cant. Oil used in all models should beSAE 10 W/30 motor oil or A.T.F, (Auto-matic Transmission Fluid). Inner forktubes (13Fig. S12-15) should extend5MM (3/16 in.) beyond top of uppertriple clamp (AFig. S12-16) on TS250 and TS 250 II models. Inner forktube should be mounted flush with topof clamp on all other models.

Rear suspension units are not repair-able and should be renewed if leakingor damaged.

REPAIRSPISTON, RINGS AND CYL-

INDER. Cylinder and piston may beremoved without dismounting enginefrom frame. Head retaining nutsshould be loosened and tightened diag-onally to prevent head warpage. Referto the following repair specifications:Maximum cylinder taper or out

of round 0.05MM(0.002 in.)

Fig. S12-1S-Distance (A) should be approxi-mately 5MM (0.20 Inch} on early modeis. TS 250R and later models should have fork inner tube

(1} top ievei with top of steering head (2).

Fig. SI2-17-Exploded view of front suspensionunits used on TM 250 modeis.

1. Stem bolt2. Handlebar clamp3. Pinchbolt4. Top crown5. Top bolt6. "O ring7. Spring seat8. Spring9. Steering stem

assembly10. Inner fork tubeU. Piston

12. Clip13. Dust cover14. Clip15. Washer16. Oil seal17. Fork cylinder18. Outer fork tube19. Cylinder lock bolt20. Stud21. Axle clamp22. Washer23. Drain screw

154

SERVICE Suzuki 250

Fig. S12-18-Exploded view of transmission typical of all models except TS 250 and TS 25011.1. Wavewasher 8. Third driven gear 15. Spacer 21. Countershaft2. Kick sUrter idle gear 9. Retaining clip 16. Drive sprocket 22. Fourth drive gear3. Ball bearing 10. Fifth driven gear 17. Oil reservoir plate 23. Third drive gear4. Thrust washer U. Second driven gear 18. Kick starter (friven 24. Fifth drive gear5. First driven gear 12. Drive shaft gear 25. Second drive gear6. Fourth driven gear 13. Ballbearing 19. Bearing holder 26. Ballbearing7. Washer 14. Oil seal 20. Ballbearing

Piston skirt to cylinder clearance 250 & TS 250 II) for cylinder clearanceTS250andTS250II . 0.18-0.19MM check at a point 52MM (2.0 in.) from

(0.0071-0.0074 in.) bottom of skirt at right angle to pinAll other models . . . . . 0.06-0.07MM hole. Measure pistons for all other

(0.0024-0.0028 in,) models at a point 26MM (1.0 in.) fromPiston ring end gap bottom of skirt at right angle to pin

Standard 0.15-0.35MM hole. Pistons and rings are available in(0.006-0.014 in.) standard and two oversizes. Piston

Wear limit l.OMM rings are Keystone type and must be(0.040 in.) installed with markings toward top.

Install piston with arrow on dome Piston made for TS 250 R and latertoward exhaust port (front) of engine, units should not be installed in earlierMeasure pistons on early models (TS models. Torque head retaining nuts to

2 kg-m (14.5 Ft.Lbs.) using a diagonalpattern.

CRANKSHAFT AND CON-NECTING ROD. Engine must beremoved from frame and crankcaseseparated to remove crankcase as-sembly. Maximum eccentricity ofcrankshaft is 0.0023 inch with crank-shaft supported on "V" blocks. Max-imum shake at small end of connectingrod is 3MM (0.118 in.). Torque primarygear retaining nut to 4.9 kg-m (36Ft.Lbs.)

CLUTCH. The wet type multi discunit is located on transmission driveshaft at right side of engine. Refer toFig. S12-11, Fig. S12-12 and Fig. S12-14. Standard thickness of friction discsis 3.5MM (0.138 in.). Discs should berenewed if less than 3.2MM (0.126 in.)thick. Steel plates should be renewed ifwarped more than 0.4MM (0.016 in.).Standard free length of clutch springsis 38.4MM (1.51 in.) and springs shouldbe renewed if less than 36.9MM (1.46in.) long.

CRANKCASE AND GEARBOX.Crankcase halves must be separated toremove the transmission. Cases shouldbe thoroughly cleaned before reas-sembly and a non hardening typegasket sealer used. Early models arenot equipped with a gasket betweencrankcase halves.

Kick starter lever and kick startershaft on early models have punchmarks that should be aligned on reas-sembly.

Fig. SI2-19-Component parts of shifter assemblyused in the late models. Shltt forks (8 A 9) are

Interchangeable.

1. Shift arm2. Shifter return spring3. Oil seal4. Shift lever5. Shift cam stopper6. Shift shaft stopper7. Shift cam guide8. Gear shift fork9. Gear shift fork

10. Shift fork shaft11. Shift pawl12. Shift pawl roller13. Cam gear

14. Shift cam15. Cam stopper plate16. Needle bearing17. Neutral switch18. "CrinB19. Neutral switch cover20. Shift fork shaft21. Shift fork22. Shift cam stopper23. Shift cam stopper

spring holder24. Shift cam reUiner

Fig. S12-20-Exploded view of TS 250 engine and transmission assembly. Minor differences may beseen between this unit and later models.

155