Haynes Yamaha Xv V Twins Manual

							
0-20 
Troubleshooting

Engine doesnt start or is difficult to start

1 Starter motor does not rotate

1 Engine kill switch Off.

2 Fuse blown. Check fuse block (Chapter 8).

3 Battery voltage low. Check and recharge battery (Chapter 8).

4 Starter motor defective. Make sure the wiring to the starter is

secure. Test starter relay (Chapter 8). If the relay is good, then the fault

is in the wiring or motor.

5 Starter relay faulty. Check it according to the procedure in

Chapter 8.

6 Starter switch not contacting. The contacts could be wet,

corroded or dirty. Disassemble and clean the switch (Chapter 8).

7 Wiring open or shorted. Check all wiring connections and

harnesses to make sure that they are dry, tight and not corroded. Also

check for broken or frayed wires that can cause a short to ground (see

wiring diagram, Chapter 8).

8 Ignition switch defective. Check the switch according to the

procedure in Chapter 8. Replace the switch with a new one if it is

defective.

9 Engine kill switch defective. Check for wet, dirty or corroded

contacts. Clean or replace the switch as necessary (Chapter 8).

2 Starter motor rotates but engine does not turn over

1 Starter motor clutch defective. Inspect and repair or replace

(Chapter 8).

2 Damaged idler or starter gears. Inspect and replace the damaged

parts (Chapter 2).

3 Starter works but engine wont turn over (seized)

Seized engine caused by one or more internally damaged

components. Failure due to wear, abuse or lack of lubrication. Damage

can include seized valves, valve lifters, camshaft, pistons, crankshaft,

connecting rod bearings, or transmission gears or bearings. Refer to

Chapter 2 for engine disassembly.

4 No fuel flow

1 No fuel in tank.

2 Fuel tap vacuum hose (if equipped) broken or disconnected.

3 Tank cap air vent obstructed. Usually caused by dirt or water.

Remove it and clean the cap vent hole.

4 Inline fuel filter clogged. Replace the filter (Chapter 1).

5 Electric fuel pump not working (if equipped). Test it according to

the procedures in Chapter 8.

6 Fuel line clogged. Pull the fuel line loose and carefully blow

through it.

7 Inlet needle valve clogged. For both of the valves to be clogged,

either a very bad batch of fuel with an unusual additive has been used,

or some other foreign material has entered the tank. Many times after a

machine has been stored for many months without running, the fuel

turns to a varnish-like liquid and forms deposits on the inlet needle

valves and jets. The carburetors should be removed and overhauled if

draining the float chambers doesnt solve the problem.

5 Engine flooded

1 Fuel level too high. Check and adjust as described in Chapter 3.

2 Inlet needle valve worn or stuck open. A piece of dirt, rust or other

debris can cause the inlet needle to seat improperly, causing excess

fuel to be admitted to the float bowl. In this case, the float chamber 
should be cleaned and the needle and seat inspected. If the needle

and seat are worn, then the leaking will persist and the parts should be

replaced with new ones (Chapter 3).

3 Starting technique incorrect. Under normal circumstances (i.e., if

all the carburetor functions are sound) the machine should start with

little or no throttle. When the engine is cold, the choke should be

operated and the engine started without opening the throttle. When the

engine is at operating temperature, only a very slight amount of throttle

should be necessary. If the engine is flooded, turn the fuel tap off and

hold the throttle open while cranking the engine. This will allow

additional air to reach the cylinders. Remember to turn the fuel tap

back on after the engine starts.

6 No spark or weak spark

1 Ignition switch Off.

2 Engine kill switch turned to the Off position.

3 Battery voltage low. Check and recharge battery as necessary

(Chapter 8).

4 Spark plug dirty, defective or worn out. Locate reason for fouled

plug(s) using spark plug condition chart and follow the plug

maintenance procedures in Chapter 1.

5 Spark plug cap or secondary (HT) wiring faulty. Check condition.

Replace either or both components if cracks or deterioration are

evident (Chapter 4).

6 Spark plug cap not making good contact. Make sure that the plug

cap fits snugly over the plug end.

7 Igniter defective. Check the unit, referring to Chapter 4 for details.

8 Pickup coil(s) defective. Check the unit(s), referring to Chapter 4

for details.

9 Ignition coil(s) defective. Check the coils, referring to Chapter 4.

10 Ignition or kill switch shorted. This is usually caused by water,

corrosion, damage or excessive wear. The switches can be

disassembled and cleaned with electrical contact cleaner. If cleaning

does not help, replace the switches (Chapter 8),

11 Wiring shorted or broken between:

a) Ignition switch and engine kill switch (or blown fuse)

b) Igniter and engine kill switch

c) Igniter and ignition coil

d) Ignition coil and plug

e) Igniter and pickup coil(s)

Make sure that all wiring connections are clean, dry and tight.

Look for chafed and broken wires (Chapters 4 and 8).

7 Compression low

1 Spark plug loose. Remove the plug and inspect the threads.

Reinstall and tighten to the specified torque (Chapter 1).

2 Cylinder head not sufficiently tightened down. If a cylinder head is

suspected of being loose, then theres a chance that the gasket or

head is damaged if the problem has persisted for any length of time.

The head nuts and bolts should be tightened to the proper torque in

the correct sequence (Chapter 2).

3 Improper valve clearance. This means that the valve is not closing

completely and compression pressure is leaking past the valve. Check

and adjust the valve clearances (Chapter 1).

4 Cylinder and/or piston worn. Excessive wear will cause

compression pressure to leak past the rings. This is usually

accompanied by worn rings as well. A top end overhaul is necessary

(Chapter 2).

5 Piston rings worn, weak, broken, or sticking. Broken or sticking

piston rings usually indicate a lubrication or carburetion problem that

causes excess carbon deposits or seizures to form on the pistons and

rings. Top end overhaul is necessary (Chapter 2).

6 Piston ring-to-groove clearance excessive. This is caused by

excessive wear of the piston ring lands. Piston replacement is

necessary (Chapter 2). 
						

							
Troubleshooting

0-21

7 Cylinder head gasket damaged. If one of the heads is allowed to

become loose, or if excessive carbon build-up on a piston crown and

combustion chamber causes extremely high compression, the head

gasket may leak. Retorquing the head is not always sufficient to

restore the seal, so gasket replacement is necessary (Chapter 2).

8 Cylinder head warped. This is caused by overheating or

improperly tightened head nuts and bolts. Machine shop resurfacing or

head replacement is necessary (Chapter 2).

9 Valve spring broken or weak. Caused by component failure or

wear; the spring(s) must be replaced (Chapter 2).

10 Valve not seating properly. This is caused by a bent valve (from

over-revving or improper valve adjustment), burned valve or seat

(improper carburetion) or an accumulation of carbon deposits on the

seat (from carburetion or lubrication problems). The valves must be

cleaned and/or replaced and the seats serviced if possible (Chapter 2).

8 Stalls after starting

1 Improper choke action. Make sure the choke lever (XV535) or

choke cable (all others) is getting a full stroke and staying in the out

position.

2 Ignition malfunction. See Chapter 4.

3 Carburetor malfunction. See Chapter 3.

4 Fuel contaminated. The fuel can be contaminated with either dirt

or water, or can change chemically if the machine is allowed to sit for

several months or more. Drain the tank and float bowls (Chapter 3).

5 Intake air leak. Check for loose carburetor-to-intake joint

connections, loose or missing vacuum gauge access port cap or hose,

or loose carburetor top (Chapter 3).

6 Engine idle speed incorrect. Turn throttle stop screw until the

engine idles at the specified rpm (Chapter 1).

9 Rough idle

1 Ignition malfunction. See Chapter 4.

2 Idle speed incorrect. See Chapter 1.

3 Carburetors not synchronized. Adjust carburetors with vacuum

gauge or manometer set as described in Chapter 1.

4 Carburetor malfunction. See Chapter 3.

5 Fuel contaminated. The fuel can be contaminated with either dirt

or water, or can change chemically if the machine is allowed to sit for

several months or more. Drain the tank and float bowls (Chapter 3).

6 Intake air leak. Check for loose carburetor-to-intake joint

connections, loose or missing vacuum gauge access port cap or hose,

or loose carburetor top (Chapter 3).

7 Air cleaner clogged. Service or replace air filter element (Chap-

ter 1).

Poor running at low speed

10 Spark weak

1 Battery voltage low. Check and recharge battery (Chapter 8).

2 Spark plug fouled, defective or worn out. Refer to Chapter 1 for

spark plug maintenance.

3 Spark plug cap or high tension wiring defective. Refer to Chapters

1 and 4 for details on the ignition system.

4 Spark plug cap not making contact.

5 Incorrect spark plug. Wrong type, heat range or cap configu-

ration. Check and install correct plugs listed in Chapter 1. A cold plug

or one with a recessed firing electrode will not operate at low speeds

without fouling.

6 Igniter defective. See Chapter 4.

7 Pickup coil(s) defective. See Chapter 4.

8 Ignition coil(s) defective. See Chapter 4. 
11 Fuel/air mixture incorrect

1 Pilot screw(s) out of adjustment (Chapters 1 and 3).

2 Pilot jet or air passage clogged. Remove and overhaul the

carburetors (Chapter 3).

3 Air bleed holes clogged. Remove carburetor and blow out all

passages (Chapter 3).

4 Air cleaner clogged, poorly sealed or missing.

5 Air cleaner-to-carburetor boot poorly sealed. Look for cracks,

holes or loose clamps and replace or repair defective parts.

6 Fuel level too high or too low. Adjust the floats (Chapter 3).

7 Fuel tank air vent obstructed. Make sure that the air vent passage

in the filler cap is open.

8 Carburetor intake joints loose. Check for cracks, breaks, tears or

loose clamps or bolts. Repair or replace the rubber boots.

12 Compression low

1 Spark plug loose. Remove the plug and inspect the threads.

Reinstall and tighten to the specified torque (Chapter 1).

2 Cylinder head not sufficiently tightened down. If the cylinder head

is suspected of being loose, then theres a chance that the gasket and

head are damaged if the problem has persisted for any length of time.

The head nuts and bolts should be tightened to the proper torque in

the correct sequence (Chapter 2).

3 Improper valve clearance. This means that the valve is not closing

completely and compression pressure is leaking past the valve. Check

and adjust the valve clearances (Chapter 1).

4 Cylinder and/or piston worn. Excessive wear will cause

compression pressure to leak past the rings. This is usually

accompanied by worn rings as well. A top end overhaul is necessary

(Chapter 2).

5 Piston rings worn, weak, broken, or sticking. Broken or sticking

piston rings usually indicate a lubrication or carburetion problem that

causes excess carbon deposits or seizures to form on the pistons and

rings. Top end overhaul is necessary (Chapter 2).

6 Piston ring-to-groove clearance excessive. This is caused by

excessive wear of the piston ring lands. Piston replacement is

necessary (Chapter 2).

7 Cylinder head gasket damaged. If a head is allowed to become

loose, or if excessive carbon build-up on the piston crown and

combustion chamber causes extremely high compression, the head

gasket may leak. Retorquing the head is not always sufficient to

restore the seal, so gasket replacement is necessary (Chapter 2).

8 Cylinder head warped. This is caused by overheating or

improperly tightened head nuts and bolts. Machine shop resurfacing or

head replacement is necessary (Chapter 2).

9 Valve spring broken or weak. Caused by component failure or

wear; the spring(s) must be replaced (Chapter 2).

10 Valve not seating properly. This is caused by a bent valve (from

over-revving or improper valve adjustment), burned valve or seat

(improper carburetion) or an accumulation of carbon deposits on the

seat (from carburetion, lubrication problems). The valves must be

cleaned and/or replaced and the seats serviced if possible (Chapter 2).

13 Poor acceleration

1 Carburetors leaking or dirty. Overhaul the carburetors (Chapter 3).

2 Timing not advancing. The pickup coil(s) or the igniter may be

defective. If so, they must be replaced with new ones, as they cant be

repaired.

3 Carburetors not synchronized. Adjust them with a vacuum gauge

set or manometer (Chapter 1).

4 Engine oil viscosity too high. Using a heavier oil than that

recommended in Chapter 1 can damage the oil pump or lubrication

system and cause drag on the engine. 
						

							
0-22 
Troubleshooting

5 Brakes dragging. Usually caused by debris which has entered the

brake piston sealing boot, or from a warped disc or bent axle. Repair

as necessary (Chapter 6).

Poor running or no power at high speed

14 Firing incorrect

1 Air filter restricted. Clean or replace filter (Chapter 1).

2 Spark plug fouled, defective or worn out. See Chapter 1 for spark

plug maintenance.

3 Spark plug cap or secondary (HT) wiring defective. See Chapters

1 and 4 for details of the ignition system.

4 Spark plug cap not in good contact. See Chapter 4.

5 Incorrect spark plug. Wrong type, heat range or cap configu-

ration. Check and install correct plugs listed in Chapter 1. A cold plug

or one with a recessed firing electrode will not operate at low speeds

without fouling.

6 Igniter defective. See Chapter 4.

7 Ignition coil(s) defective. See Chapter 4. ,

15 Fuel/air mixture incorrect

1 Main jet clogged. Dirt, water or other contaminants can clog the

main jets. Clean the fuel tap filter, the float bowl area, and the jets and

carburetor orifices (Chapter 3).

2 Main jet wrong size. The standard jetting is for sea level

atmospheric pressure and oxygen content.

3 Throttle shaft-to-carburetor body clearance excessive. Refer to

Chapter 3 for inspection and part replacement procedures.

4 Air bleed holes clogged. Remove and overhaul carburetors

(Chapter 3).

5 Air cleaner clogged, poorly sealed, or missing.

6 Air cleaner-to-carburetor boot poorly sealed. Look for cracks,

holes or loose clamps, and replace or repair defective parts.

7 Fuel level too high or too low. Adjust the float(s) (Chapter 3).

8 Fuel tank air vent obstructed. Make sure the air vent passage in

the filler cap is open.

9 Carburetor intake joints loose. Check for cracks, breaks, tears or

loose clamps or bolts. Repair or replace the rubber boots (Chapter 3).

10 Fuel tap clogged. Remove the tap and clean it (Chapter 1).

11 Fuel line clogged. Pull the fuel line loose and carefully blow

through it.

16 Compression low

1 Spark plug loose. Remove the plug and inspect the threads.

Reinstall and tighten to the specified torque (Chapter 1).

2 Cylinder head not sufficiently tightened down. If a cylinder head is

suspected of being loose, then theres a chance that the gasket and

head are damaged if the problem has persisted for any length of time.

The head nuts and bolts should be tightened to the proper torque in

the correct Sequence (Chapter 2).

3 Improper valve clearance. This means that the valve is not closing

completely and compression pressure is leaking past the valve. Check

and adjust the valve clearances (Chapter 1).

4 Cylinder and/or piston worn. Excessive wear will cause

compression pressure to leak past the rings. This is usually

accompanied by worn rings as well. A top end overhaul is necessary

(Chapter 2).

5 Piston rings worn, weak, broken, or sticking. Broken or sticking

piston rings usually indicate a lubrication or carburetion problem that

causes excess carbon deposits or seizures to form on the pistons and

rings. Top end overhaul is necessary (Chapter 2).

6 Piston ring-to-groove clearance excessive. This is caused by

excessive wear of the piston ring lands. Piston replacement is 
necessary (Chapter 2).

7 Cylinder head gasket damaged. If a head is allowed to become

loose, or if excessive carbon build-up on the piston crown and

combustion chamber causes extremely high compression, the head

gasket may leak. Retorquing the head is not always sufficient to

restore the seal, so gasket replacement is necessary (Chapter 2).

8 Cylinder head warped. This is caused by overheating or

improperly tightened head nuts and bolts. Machine shop resurfacing or

head replacement is necessary (Chapter 2).

9 Valve spring broken or weak. Caused by component failure or

wear; the spring(s) must be replaced (Chapter 2).

10 Valve not seating properly. This is caused by a bent valve (from

over-revving or improper valve adjustment), burned valve or seat

(improper carburetion) or an accumulation of carbon deposits on the

seat (from carburetion or lubrication problems). The valves must be

cleaned and/or replaced and the seats serviced if possible (Chapter 2).

17 Knocking or pinging

1 Carbon build-up in combustion chamber. Use of a fuel additive

that will dissolve the adhesive bonding the carbon particles to the

crown and chamber is the easiest way to remove the build-up.

Otherwise, the cylinder head will have to be removed and

decarbonized (Chapter 2).

2 Incorrect or poor quality fuel. Old or improper grades of fuel can

cause detonation. This causes the piston to rattle, thus the knocking or

pinging sound. Drain old fuel and always use the recommended fuel

grade.

3 Spark plug heat range incorrect. Uncontrolled detonation

indicates the plug heat range is too hot. The plug in effect becomes a

glow plug, raising cylinder temperatures. Install the proper heat range

plug (Chapter 1).

4 Improper air/fuel mixture. This will cause the cylinder to run hot,

which leads to detonation. Clogged jets or an air leak can cause this

imbalance. See Chapter 3.

18 Miscellaneous causes

1 Throttle valve doesnt open fully. Adjust the cable slack (Chap-

ter 1).

2 Clutch slipping. May be caused by a cable that is improperly

adjusted or loose or worn clutch components. Refer to Chapter 2 for

cable replacement and clutch overhaul procedures.

3 Timing not advancing.

4 Engine oil viscosity too high. Using a heavier oil than the one

recommended in Chapter 1 can damage the oil pump or lubrication

system and cause drag on the engine.

5 Brakes dragging. Usually caused by debris which has entered the

brake piston sealing boot, or from a warped disc or bent axle. Repair

as necessary.

Overheating

19 Engine overheats

1 Engine oil level low. Check and add oil (Chapter 1).

2 Wrong type of oil. If youre not sure what type of oil is in the

engine, drain it and fill with the correct type (Chapter 1).

3 Air leak at carburetor intake joints. Check and tighten or replace

as necessary (Chapter 3).

4 Fuel level low. Check and adjust if necessary (Chapter 3).

5 Worn oil pump or clogged oil passages. Replace pump or clean

passages as necessary.

6 Clogged external oil lines (if equipped). Remove and check for

foreign material (see Chapter 2).

7 Carbon build-up in combustion chambers. Use of a fuel additive 
						

							
Troubleshooting

0-23

that will dissolve the adhesive bonding the carbon particles to the

piston crowns and chambers is the easiest way to remove the build-

up. Otherwise, the cylinder heads will have to be removed and

decarbonized (Chapter 2).

20 Firing incorrect

1 Spark plug fouled, defective or worn out. See Chapter 1 for spark

plug maintenance.

2 Incorrect spark plug (see Chapter 1).

3 Faulty ignition coil(s) (Chapter 4).

21 Fuel/air mixture incorrect

1 Main jet clogged. Dirt, water and other contaminants can clog the

main jets. Clean the fuel tap filter, the float bowl area and the jets and

carburetor orifices (Chapter 3).

2 Main jet wrong size. The standard jetting is for sea level

atmospheric pressure and oxygen content.

3 Air cleaner poorly sealed or missing.

4 Air cleaner-to-carburetor boot poorly sealed. Look for cracks,

holes or loose clamps and replace or repair.

5 Fuel level too low. Adjust the float(s) (Chapter 3).

6 Fuel tank air vent obstructed. Make sure that the air vent passage

in the filler cap is open.

7 Carburetor intake joints loose. Check for cracks, breaks, tears or

loose clamps or bolts. Repair or replace the rubber boots (Chapter 3).

22 Compression too high

1 Carbon build-up in combustion chamber. Use of a fuel additive

that will dissolve the adhesive bonding the carbon particles to the

piston crown and chamber is the easiest way to remove the build-up.

Otherwise, the cylinder head will have to be removed and

decarbonized (Chapter 2).

2 Improperly machined head surface or installation of incorrect

gasket during engine assembly.

23 Engine load excessive

1 Clutch slipping. Can be caused by damaged, loose or worn clutch

oonents. Refer to Chapter 2 for overhaul procedures.

Engine oil level too high. The addition of too much oil will cause

pressurization of the crankcase and inefficient engine operation. Check

Specifications and drain to proper level (Chapter 1).

3 Engine oil viscosity too high. Using a heavier oil than the one

recommended in Chapter 1 can damage the oil pump or lubrication

system as well as cause drag on the engine.

4 Brakes dragging. Usually caused by debris which has entered the

brake piston sealing boot, or from a warped disc or bent axle. Repair

as necessary.

24 Lubrication inadequate

1 Engine oil level too low. Friction caused by intermittent lack of

lubrication or from oil that is overworked can cause overheating. The

oil provides a definite cooling function in the engine. Check the oil level

(Chapter 1).

2 Poor quality engine oil or incorrect viscosity or type. Oil is rated

not only according to viscosity but also according to type. Some oils

are not rated high enough for use in this engine. Check the Specifi-

cations section and change to the correct oil (Chapter 1).

3 Camshaft or journals worn. Excessive wear causing drop in oil 
pressure. Replace cam, bushing or cylinder head. Abnormal wear

could be caused by oil starvation at high rpm from low oil level or

improper viscosity or type of oil (Chapter 1).

4 Crankshaft and/or bearings worn. Same problems as para-

graph 3. Check and replace crankshaft and/or bearings (Chapter 2).

25 Miscellaneous causes

Modification to exhaust system. Most aftermarket exhaust

systems cause the engine to run leaner, which make them run hotter.

When installing an accessory exhaust system, always rejet the

carburetors.

Clutch problems

26 Clutch slipping

1 Friction plates worn or warped. Overhaul the clutch assembly

(Chapter 2).

2 Steel plates worn or warped (Chapter 2).

3 Clutch spring(s) broken or weak. Old or heat-damaged spring(s)

(from slipping clutch) should be replaced with new ones (Chapter 2).

4 Clutch release mechanism defective. Replace any defective parts

(Chapter 2).

5 Clutch boss or housing unevenly worn. This causes improper

engagement of the plates. Replace the damaged or worn parts

(Chapter 2).

27 Clutch not disengaging completely

1 Clutch lever play excessive (see Chapter 1). Clutch cable

improperly adjusted (see Chapter 1).

2 Clutch plates warped or damaged. This will cause clutch drag,

which in turn will cause the machine to creep. Overhaul the clutch

assembly (Chapter 2).

3 Usually caused by a sagged or broken spring(s). Check and

replace the spring(s) (Chapter 2).

4 Engine oil deteriorated. Old, thin, worn out oil will not provide

proper lubrication for the discs, causing the clutch to drag. Replace the

oil and filter (Chapter 1).

5 Engine oil viscosity too high. Using a thicker oil than

recommended in Chapter 1 can cause the plates to stick together,

putting a drag on the engine. Change to the correct viscosity oil

(Chapter 1).

6 Clutch housing seized on shaft. Lack of lubrication, severe wear

or damage can cause the housing to seize on the shaft. Overhaul of the

clutch, and perhaps transmission, may be necessary to repair the

damage (Chapter 2).

7 Clutch release mechanism defective. Worn or damaged release

mechanism parts can stick and fail to apply force to the pressure plate.

Overhaul the release mechanism (Chapter 2).

8 Loose clutch boss nut. Causes housing and boss misalignment

putting a drag on the engine. Engagement adjustment continually

varies. Overhaul the clutch assembly (Chapter 2).

Gear shifting problems

28 Doesnt go into gear or lever doesnt return

1- Clutch not disengaging. See Section 27.

2 Shift fork(s) bent or seized. Often caused by dropping the

machine or from lack of lubrication. Overhaul the transmission

(Chapter 2). 
						

							
0-24 
Troubleshooting

3 Gear(s) stuck on shaft. Most often caused by a lack of lubrication

or excessive wear in transmission bearings and bushings. Overhaul the

transmission (Chapter 2).

4 Shift cam binding. Caused by lubrication failure or excessive

wear. Replace the cam and bearing (Chapter 2).

5 Shift lever return spring weak or broken (Chapter 2).

6 Shift lever broken. Splines stripped out of lever or shaft, caused

by allowing the lever to get loose or from dropping the machine.

Replace necessary parts (Chapter 2).

7 Shift mechanism pawl broken or worn. Full engagement and

rotary movement of shift drum results. Replace shaft assembly

(Chapter 2).

8 Pawl spring broken. Allows pawl to float, causing sporadic shift

operation. Replace spring (Chapter 2).

29 Jumps out of gear

1 Shift fork(s) worn. Overhaul the transmission (Chapter 2).

2 Gear groove(s) worn. Overhaul the transmission (Chapter 2).

3 Gear dogs or dog slots worn or damaged. The gears should be

inspected and replaced. No attempt should be made to service the

worn parts.

30 Overshifts

1 Pawl spring weak or broken (Chapter 2).

2 Shift drum stopper lever not functioning (Chapter 2).

Abnormal engine noise

31 Knocking or pinging

1 Carbon build-up in combustion chamber. Use of a fuel additive

that will dissolve the adhesive bonding the carbon particles to the

piston crown and chamber is the easiest way to remove the build-up.

Otherwise, the cylinder head will have to be removed and

decarbonized (Chapter 2).

2 Incorrect or poor quality fuel. Old or improper fuel can cause

detonation. This causes the pistons to rattle, thus the knocking or

pinging sound. Drain the old fuel and always use the recommended

grade fuel (Chapter 1).

3 Spark plug heat range incorrect. Uncontrolled detonation

indicates that the plug heat range is too hot. The plug in effect

becomes a glow plug, raising cylinder temperatures. Install the proper

heat range plug (Chapter 1).

4 Improper air/fuel mixture. This will cause the cylinders to run hot

and lead to detonationrClogged jets or an air leak can cause this

imbalance. See Chapter 3.

32 Piston slap or rattling

1 Cylinder-to-piston clearance excessive. Caused by improper

assembly. Inspect and overhaul top end parts (Chapter 2).

2 Connecting rod bent. Caused by over-revving, trying to start a

badly flooded engine or from ingesting a foreign object into the

combustion chamber. Replace the damaged parts (Chapter 2).

3 Piston pin or piston pin bore worn or seized from wear or lack of

lubrication. Replace damaged parts (Chapter 2).

4 Piston ring(s) worn, broken or sticking. Overhaul the top end

(Chapter 2).

5 Piston seizure damage. Usually from lack of lubrication or

overheating. Replace the pistons and bore the cylinders, as necessary

(Chapter 2). 
6 Connecting rod upper or lower end clearance excessive. Caused

by excessive wear or lack of lubrication. Replace worn parts.

33 Valve noise

1 Incorrect valve clearances. Adjust the clearances by referring to

Chapter 1.

2 Valve spring broken or weak. Check and replace weak valve

springs (Chapter 2).

3 Camshaft, bushing or cylinder head worn or damaged. Lack of

lubrication at high rpm is usually the cause of damage. Insufficient oil

or failure to change the oil at the recommended intervals are the chief

causes.

34 Other noise

1 Cylinder head gasket leaking.

2 Exhaust pipe leaking at cylinder head connection. Caused by

improper fit of pipe(s) or loose exhaust flange. All exhaust fasteners

should be tightened evenly and carefully. Failure to do this will lead to

a leak.

3 Crankshaft runout excessive. Caused by a bent crankshaft (from

over-revving) or damage from an upper cylinder component failure.

Can also be attributed to dropping the machine on either of the

crankshaft ends.

4 Engine mounting bolts or nuts loose. Tighten all engine mounting

bolts and nuts to the specified torque (Chapter 2).

5 Crankshaft bearings worn (Chapter 2).

6 Camshaft chain tensioner(s) defective. Replace according to the

procedure in Chapter 2.

7 Camshaft chain, sprockets or guides worn (Chapter 2).

Abnormal driveline noise

35 Clutch noise

1 Clutch housing/friction plate clearance excessive (Chapter 2).

2 Loose or damaged clutch pressure plate and/or bolts (Chapter 2).

36 Transmission noise

1 Bearings worn. Also includes the possibility that the shafts are

worn. Overhaul the transmission (Chapter 2).

2 Gears worn or chipped (Chapter 2).

3 Metal chips jammed in gear teeth. Probably pieces from a broken

clutch, gear or shift mechanism that were picked up by the gears. This

will cause early bearing failure (Chapter 2).

4 Engine oil level too low. Causes a howl from transmission. Also

affects engine power and clutch operation (Chapter 1).

37 Final drive noise

1 Chain not adjusted properly (if equipped) (Chapter 1).

2 Engine sprocket or rear sprocket loose (chain drive models).

Tighten fasteners (Chapter 5).

3 Sprocket(s) worn (chain drive models). Replace sprocket(s).

(Chapter 5).

4 Rear sprocket warped (chain drive models). Replace (Chapter 5).

5 Wheel coupling (cush drive) worn (chain drive models). Replace

coupling (Chapter 5).

6 Final drive oil level low (shaft drive models).

7 Final drive gear lash out of adjustment (shaft drive models).

8 Final drive gears damaged or worn (shaft drive models). 
						

							
Troubleshooting 
0-25

Abnormal frame and suspension noise

38 Front end noise

1 Low fluid level or improper viscosity oil in forks. This can sound

like spurting and is usually accompanied by irregular fork action

(Chapter 5).

2 Spring weak or broken. Makes a clicking or scraping sound. Fork

oil, when drained, will have a lot of metal particles in it (Chapter 5).

3 Steering head bearings loose or damaged. Clicks when braking.

Check and adjust or replace as necessary (Chapter 5).

4 Fork triple clamps loose. Make sure all triple clamp pinch bolts

are tight (Chapter 5).

5 Fork tube bent. Good possibility if machine has been dropped.

Replace tube with a new one (Chapter 5).

6 Front axle or axle clamp bolt loose. Tighten them to the specified

torque (Chapter 6).

39 Shock absorber noise

1 Fluid level incorrect. Indicates a leak caused by defective seal.

Shock will be covered with oil. Replace shock (Chapter 5).

2 Defective shock absorber with internal damage. This is in the

body of the shock and cant be remedied. The shock must be replaced

with a new one (Chapter 5).

3 Bent or damaged shock body. Replace the shock with a new one

(Chapter 5).

40 Brake noise

1 Squeal caused by pad shim not installed or positioned correctly

(Chapter 6).

2 Squeal caused by dust on brake pads. Usually found in

combination with glazed pads. Clean using brake cleaning solvent

(Chapter 6).

3 Contamination of brake pads. Oil, brake fluid or dirt causing brake

to chatter or squeal. Clean or replace pads (Chapter 6).

4 Pads glazed. Caused by excessive heat from prolonged use or

from contamination. Do not use sandpaper, emery cloth, carborundum

cloth or any other abrasive to roughen the pad surfaces as abrasives

will stay in the pad material and damage the disc. A very fine flat file

can be used, but pad replacement is suggested as a cure (Chapter 6).

5 Disc warped. Can cause a chattering, clicking or intermittent

squeal. Usually accompanied by a pulsating lever and uneven braking.

Replace the disc (Chapter 6).

6 Drum brake linings worn or contaminated. Can cause scraping or

squealing. Replace the shoes (Chapter 6).

7 Drum brake linings warped or worn unevenly. Can cause

chattering. Replace the linings (Chapter 6).

8 Brake drum out of round. Can cause chattering. Replace brake

drum (Chapter 6).

9 Loose or worn wheel bearings. Check and replace as needed

(Chapter 6).

Oil level indicator light comes on

41 Engine lubrication system

1 Yamaha XV700 through 1100 models use an oil level light rather

than an oil pressure light.

2 Engine oil level low. Inspect for leak or other problem causing low

oil level and add recommended oil (Chapters 1 and 2). 
42 Electrical system

1 Oil level switch defective. Check the switch according to the

procedure in Chapter 8. Replace it if its defective.

2 Oil level indicator light circuit defective. Check for pinched,

shorted, disconnected or damaged wiring (Chapter 8).

Excessive exhaust smoke

43 White smoke

1 Piston oil ring worn. The ring may be broken or damaged, causing

oil from the crankcase to be pulled past the piston into the combustion

chamber. Replace the rings with new ones (Chapter 2).

2 Cylinders worn, cracked, or scored. Caused by overheating or oil

starvation. If worn or scored, the cylinders will have to be rebored and

new pistons installed. If cracked, the cylinder block will have to be

replaced (see Chapter 2).

3 Valve oil seal damaged or worn. Replace oil seals with new ones

(Chapter 2).

4 Valve guide worn. Perform a complete valve job (Chapter 2).

5 Engine oil level too high, which causes the oil to be forced past

the rings. Drain oil to the proper level (Chapter 1).

6 Head gasket broken between oil return and cylinder. Causes oil to

be pulled into the combustion chamber. Replace the head gasket and

check the head for warpage (Chapter 2).

7 Abnormal crankcase pressurization, which forces oil past the

rings. Clogged breather or hoses usually the cause (Chapter 2).

44 Black smoke

1 Air cleaner clogged. Clean or replace the element (Chapter 1).

2 Main jet too large or loose. Compare the jet size to the Specifi-

cations (Chapter 3).

3 Choke stuck, causing fuel to be pulled through choke circuit

(Chapter 3).

4 Fuel level too high. Check and adjust the float level as necessary

(Chapter 3).

5 Inlet needle held off needle seat. Clean the float bowls and fuel

line and replace the needles and seats if necessary (Chapter 3).

45 Brown smoke

1 Main jet too small or clogged. Lean condition caused by wrong

size main jet or by a restricted orifice. Clean float bowl and jets and

compare jet size to Specifications (Chapter 3).

2 Fuel flow insufficient. Fuel inlet needle valve stuck closed due to

chemical reaction with old fuel. Float level incorrect. Restricted fuel

line. Clean line and float bowl and adjust floats if necessary.

3 Carburetor intake manifolds loose (Chapter 3).

4 Air cleaner poorly sealed or not installed (Chapter 1).

Poor handling or stability

46 Handlebar hard to turn

1 Steering stem locknut too tight (Chapter 5).

2 Bearings damaged. Roughness can be felt as the bars are turned

from side-to-side. Replace bearings and races (Chapter 5).

3. Races dented or worn. Denting results from wear in only one

position (e.g., straight ahead), from a collision or hitting a pothole or

from dropping the machine. Replace races and bearings (Chapter 5).

4 Steering stem lubrication inadequate. Causes are grease getting 
						

							
0-26 
Troubleshooting

hard from age or being washed out by high pressure car washes.

Disassemble steering head and repack bearings (Chapter 5).

5 Steering stem bent. Caused by a collision, hitting a pothole or by

dropping the machine. Replace damaged part. Dont try to straighten

the steering stem (Chapter 5).

6 Front tire air pressure too low (Chapter 1).

47 Handlebar shakes or vibrates excessively

1 Tires worn or out of balance (Chapter 1 or 6).

2 Swingarm bearings worn. Replace worn bearings by referring to

Chapter 6.

3 Rim(s) warped or damaged. Inspect wheels for runout (Chapter 6).

4 Wheel bearings worn. Worn front or rear wheel bearings can

cause poor tracking. Worn front bearings will cause wobble (Chap-

ter 6).

5 Handlebar clamp bolts or bracket nuts loose (Chapter 5).

6 Steering stem or fork clamps loose. Tighten them to the specified

torque (Chapter 5).

7 Motor mount bolts loose. Will cause excessive vibration with

increased engine rpm (Chapter 2).

48 Handlebar pulls to one side

1 Frame bent. Definitely suspect this if the machine has been

dropped. May or may not be accompanied by cracking near the bend.

Replace the frame (Chapter 5).

2 Wheel out of alignment. Caused by improper location of axle

spacers or from bent steering stem or frame (Chapter 5).

3 Swingarm bent or twisted. Caused by age (metal fatigue) or

impact damage. Replace the swingarm (Chapter 5).

4 Steering stem bent. Caused by impact damage or by dropping

the motorcycle. Replace the steering stem (Chapter 5).

5 Fork leg bent. Disassemble the forks and replace the damaged

parts (Chapter 5).

6 Fork oil level uneven. Check and add or drain as necessary

(Chapter 5).

49 Poor shock absorbing qualities

1 Too hard:

a) Fork oil level excessive (Chapter 5).

b) Fork oil viscosity too high. Use a lighter oil (see the Specifications

in Chapter 1).

c) Fork tube bent. Causes a harsh, sticking feeling (Chapter 5).

d) Shock shaft or body bent or damaged (Chapter 5).

e) Fork internal damage (Chapter 5).

f) Shock internal damage.

g) Tire pressure too high (Chapters 1 and 6).

2 Too soft:

a) Fork or shock oil insufficient and/or leaking (Chapter 5).

b) Fork oil level too low (Chapter 5).

c) Fork oil viscosity too light (Chapter 5).

d) Fork springs weak or broken (Chapter 5).

Braking problems

50 Front brakes are spongy, dont hold

1 Air in brake line. Caused by inattention to master cylinder fluid

level or by leakage. Locate problem and bleed brakes (Chapter 6).

2 Pad or disc worn (Chapters 1 and 6).

3 Brake fluid leak. See paragraph 1. 
4 Contaminated pads. Caused by contamination with oil, grease,

brake fluid, etc. Clean or replace pads. Clean disc thoroughly with

brake cleaner (Chapter 6).

5 Brake fluid deteriorated. Fluid is old or contaminated. Drain

system, replenish with new fluid and bleed the system (Chapter 6).

6 Master cylinder internal parts worn or damaged causing fluid to

bypass (Chapter 6).

7 Master cylinder bore scratched by foreign material or broken

spring. Repair or replace master cylinder (Chapter 6).

8 Disc warped. Replace disc (Chapter 6).

51 Brake lever or pedal pulsates

1 Disc warped. Replace disc (Chapter 6).

2 Axle bent. Replace axle (Chapter 5).

3 Brake caliper bolts loose (Chapter 6).

4 Brake caliper shafts damaged or sticking, causing caliper to bind.

Lube the shafts or replace them if they are corroded or bent (Chap-

ter 6).

5 Wheel warped or otherwise damaged (Chapter 6).

6 Wheel bearings damaged or worn (Chapter 6).

7 Brake drum out of round. Replace brake drum (Chapter 6).

52 Brakes drag

1 Master cylinder piston seized. Caused by wear or damage to

piston or cylinder bore (Chapter 6).

2 Lever balky or stuck. Check pivot and lubricate (Chapter 6).

3 Brake caliper binds. Caused by inadequate lubrication or damage

to caliper shafts (Chapter 6).

4 Brake caliper piston seized in bore. Caused by wear or ingestion

of dirt past deteriorated seal (Chapter 6),

5 Brake pad damaged. Pad material separated from backing plate.

Usually caused by faulty manufacturing process or from contact with

chemicals. Replace pads (Chapter 6).

6 Pads improperly installed (Chapter 6).

7 Rear brake pedal free play insufficient (Chapter 1).

8 Rear brake springs weak. Replace brake springs (Chapter 6).

Electrical problems

53 Battery dead or weak

1 Battery faulty. Caused by sulfated plates which are shorted

through sedimentation or low electrolyte level. Also, broken battery

terminal making only occasional contact (Chapter 8).

2 Battery cables making poor contact (Chapter 8).

3 Load excessive. Caused by addition of high wattage lights or

other electrical accessories.

4 Ignition switch defective. Switch either grounds/earths internally

or fails to shut off system. Replace the switch (Chapter 8).

5 Regulator/rectifier defective (Chapter 8).

6 Stator coil open or shorted (Chapter 8).

7 Wiring faulty. Wiring grounded or connections loose in ignition,

charging or lighting circuits (Chapter 8).

54 Battery overcharged

1 Regulator/rectifier defective. Overcharging is noticed when

battery gets excessively warm or boils over (Chapter 8).

2 Battery defective. Replace battery with a new one (Chapter 8).

3 Battery amperage too low, wrong type or size. Install

manufacturers specified amp-hour battery to handle charging load

(Chapter 8). 
						

							
1-1

Chapter 1

Tune-up and routine maintenance

Contents

Section

Air filter element - servicing 14

Battery electrolyte level/specific gravity - check 4

Brake lever and pedal position and play - check and adjustment. 7

Brake pads and shoes - wear check 5

Brake system - general check 6

Carburetor synchronization - check and adjustment 20

Clutch - check and adjustment 10

Crankcase ventilation system - inspection 21

Cylinder compression - check 15

Drive chain and sprockets (chain drive models) - check,

adjustment and lubrication 11

Engine oil/filter - change 13

Exhaust system - check 22

Fasteners - check 24

Final drive oil (shaft drive models) - check and change 12 
Section

Fluid levels - check 3

Fuel system - check and filter cleaning or replacement 25

Idle speed - check and adjustment 19

Introduction to tune-up and routine maintenance 2

Lubrication - general 17

Shift linkage adjustment 27

Spark plugs - replacement 16

Steering head bearings - check, adjustment and lubrication 23

Suspension adjustments 28

Suspension - check 26

Throttle and choke operation/grip freeplay - check

. and adjustment 9

Tires/wheels - general check 8

Valve clearances - check and adjustment 18

Yamaha XV Routine maintenance intervals 1 
						

							
1-2

Chapter 1 Tune-up and routine maintenance

Specifications

XV535

Engine

Spark plugs

Type NGK BP7ES or ND W22EP-U

Gap 0.7 to 0.8 mm (0.028 to 0.032 inch)

Valve clearances (COLD engine)

Intake 0.07 to 0.12 mm (0.003 to 0.005 inch)

Exhaust 0.12 to 0.17 mm (0.005 to 0.007 inch)

Engine idle speed 1150 to 1250 rpm

Cylinder compression pressure (at sea level)

Standard 10.75 Bars (156 psi)

Maximum... 11.78 Bars (171 psi)

Minimum 9.78 Bars (142 psi)

Maximum difference between cylinders 0.96 Bars (14 psi)

Carburetor synchronization

Vacuum at idle speed 230 mm Hg (9.06 inch Hg)

Maximum vacuum difference between cylinders 10 mm Hg (0.39 inch Hg)

Cylinder numbering (from rear to front of bike)... 1-2

Miscellaneous

Brake pedal position.. . 38 mm (1.5 inch) above the top of the footpeg

Shift pedal position 50 to 60 mm (2.0 to 2.4 inches) above the top of the footpeg

Freeplay adjustments

Throttle grip 2 to 5 mm (0.08 to 0.20 inch)

Clutch lever 2 to 3 mm (0.08 to 0.12 inch)

Front brake lever 2 to 5 mm (0.08 to 0.20 inch)

Rear brake pedal .... 20 to 30 mm (0.8 to 1.2 inches)

Battery electrolyte specific gravity 1.280 at 20-degrees C (68-degrees F)

Minimum tire tread depth* 1 mm (0.04 inch)

Tire pressures (cold)

Front

1987 and 1988 US, all UK models... 1.93 Bars (28 psi)

1989 and later US models 1.99 Bars (29 psi)

Rear

Up to 90 kg (198 lbs)

1987 and 1988 US, all UK models 2.2 Bars (32 psi)

1989 and later US models . 2.27 Bars (33 psi)

Above 90 kg (198 lbs) or high speed riding 2.48 bars (36 psi)

Torque specifications

Oil drain plug 43 Nm (31 ft-lbs)

Oil filter cover bolts 10 Nm (7.2 ft-lbs)

Spark plugs 12.5 Nm (9 ft-lbs)

Steering head bearing ring nuts

Initial torque 38 Nm (27 ft-lbs)

Final torque 10 Nm (7.2 ft-lbs)

Steering stem bolt 54 Nm (39 ft-lbs)

Valve adjuster locknuts . 14 Nm (10 ft-lbs)

Rocker cover bolts 10 Nm (7.2 ft-lbs)

Final drive filler and drain plugs 23 Nm (17 ft-lbs)

Recommended lubricants and fluids

Fuel type

US . Unleaded

UK Regular

Fuel capacity

1987 and 1988 models

Total......... 8.6 liters (2.3 US gal, 1.9 Imp gal)

Reserve 2.0 liters (0.5 US gal, 0.4 Imp gal)

1989 and later models

Total . 13.5 liters (3.6 US gal, 3.0 Imp gal)

Reserve.. 2.5 liters (0.7 US gal, 0.5 Imp gal)

Engine/transmission oil

Type API grade SE or SF 
						

							
Chapter 1 Tune-up and routine maintenance

1-3

Viscosity

Consistently below 15 degrees C (60 degrees F) SAE 10W30

Consistently above 5 degrees C (40 degrees F) SAE 20W40

Capacity

With filter change 2.8 liters (3.0 US qt, 5.0 Imperial pt)

Oil change only 2.6 liters (2.7 US qt, 4.6 Imperial pt)

Brake fluid .. DOT 4

Final gear

Type SAE 80 API GL-4 hypoid gear oil

Capacity 0.19 liters (0.2 US qt, 0.34 Imp pt

Wheel bearings Medium weight, lithium-based multi-purpose grease

Swingarm pivot bearings . Medium weight, lithium-based multi-purpose grease

Cables and lever pivots Chain and cable lubricant or 10W30 motor oil

Sidestand/centerstand pivots Chain and cable lubricant or 10W30 motor oil

Brake pedal/shift lever pivots Chain and cable lubricant or 10W30 motor oil

Throttle grip Multi-purpose grease or dry film lubricant

In the UK, tread depth must be at least 1 mm over 3/4 of the tread breadth all the way around the tire, with no bald patches.

1981 through 1983 XV750 through 1000 models and all TR1

Engine

Spark plugs

Type NGK BP7ES or ND W22EP-U

Gap... 0.7 to 0.8 mm (0.028 to 0.032 inch)

Valve clearances (COLD engine)

Intake 0.10 mm (0.004 inch)

Exhaust 0.15 mm (0.006 inch)

Engine idle speed .. 950 to 1050 rpm

Cylinder compression pressure (at sea level)

XV750 and TR1 Not specified

XV920 . 9.30 Bars (135 psi) at 300 rpm

Carburetor synchronization

Vacuum at idle speed  180 +/-10 mm Hg (7.09 +/- 0.4 inch Hg)

Maximum vacuum difference between cylinders 10 mm Hg (0.4 inch Hg)

Cylinder numbering (from rear to front of bike) 1-2

Miscellaneous

Brake pedal position Not specified

Shift pedal position Not specified

Freeplay adjustments

Throttle grip Not specified

Clutch lever 2 to 3 mm (0.08 to 0.12 inch)

Front brake lever 5 to 8 mm (0.20 to 0.30 inch)

Rear brake pedal 20 to 30 mm (0.8 to 1.2 inches)

Battery electrolyte specific gravity 1.280 at 20-degrees C (68-degrees F)

Minimum tire tread depth* 1 mm (0.04 inch)

Tire pressures (cold)

XV750, XV920 K and MK

Front

Up to 90 kg (198 lbs) load 1.79 Bars (26 psi)

90 to 160 kg (198 to 353 lbs) load 1.93 Bars (28 psi)

High speed riding 2.20 Bars (32 psi)

Rear

Up to 90 kg (198 lbs) 1.93 Bars (28 psi)

90 to 160 kg (198 to 353 lbs) 2.48 bars (36 psi)

High speed riding 2.20 Bars (32 psi)

XV920J

Front

Up to 90 kg (198 lbs) load 1.79 Bars (26 psi)

90 to 213 kg (198 to 470 lbs) load 1.93 Bars (28 psi)

High speed riding 2.20 Bars (32 psi)

Rear

Up to 90 kg (198 lbs) 1.93 Bars (28 psi)

90 to 213 kg (198 to 470 lbs) 2.76 bars (40 psi)

High speed riding 2.48 Bars (36 psi)