Haynes Yamaha Xv V Twins Manual

							
2B-46 
Chapter 2 Part B Engine, clutch and transmission (XV700-1100 models)

26.9h Transmission shafts (XV700-1100 models) -

exploded view

1 Mainshaft

2 Fourth pinion gear

3 Second-third pinion gear

4 Fifth pinion gear

5 Fifth wheel gear

6 Second wheel gear

7 Driveaxle

8 Third wheel gear

9 Fourth wheel gear

10 Middle drive gear

11 First wheel gear

12 Middle driveshaft

13 Middle driven shaft

14 Middle driven gear

15 Oil pump drive sprocket

26.10a Slide the fifth wheel gear off the driveaxle 
26.10b Remove the snap-ring , 
						

							
Chapter 2 Part B Engine, clutch and transmission (XV700-1100 models)

2B-47

26.10c ... and the thrust washer ...

26.10d ... and slide second wheel

gear off 
26,1 Oe At the other end of the driveaxle,

slide off the middle drive gear ...

26.10f ... the first wheel gear ...

26.1 Og ... and the fourth wheel gear

26.10h Remove the snap-ring ...

26.101 ... and the thrust washer ...

26.10J ... and the third wheel gear ...

26.10k ... from the driveaxle

Driveaxle

Refer to illustrations 26.10a through 26.10k

10 To disassemble the driveaxle, refer to the accompanying

illustrations. Slide each gear onto a rod, such a wooden dowel or

plastic pipe, as soon as its removed from the shaft. 
Inspection

Refer to illustrations 26.12, 26.15, 26.19 and 26.20

11 Wash all of the components in clean solvent and dry them off.

Rotate the ball bearings in the left side of the transmission case, feeling

for tightness, rough spots and excessive looseness and listening for 
						

							
2B-48 
Chapter 2 Part B Engine, clutch and transmission (XV700-1100 models)

26.12 Check the gear bushings (if

equipped) for wear or damage 
26.15 Check the teeth, splines and

bearing on the middle drive gear 
26.19 The stopper plate can be left in

position unless its loose or the

crankcases are to be replaced - if you

remove it, use Loctite Stud n Bearing

Mount or equivalent on the screw threads

noises. If any of these conditions are found, replace the bearing with a

blind hole puller (see illustrations 21.4b and 21.4c). Check the oil seal

behind the mainshaft bearing; its a good idea to replace it as a

precaution (see Section 21).

13 Check the gear teeth for cracking and other obvious damage.

Check the gear bushings and the surface in the inner diameter of each

gear for scoring or heat discoloration (see illustration). If the gear or

bushing is damaged, replace it.

13 Inspect the dogs and the dog holes in Hie gears for excessive

wear. Replace the paired gears as a set if necessary.

14 Place the shaft in V-blocks and check runout with a dial indicator.

Replace the shaft if runout exceeds the value listed in this Chapters

Specifications.

15 Ifyoure working on a shaft drive model, inspect the middle drive

gear (see illustration). Replace the gear if the teeth or splines are worn

or damaged. Replace the bearing if its loose, rough or noisy.

16 Check the edges of the grooves in the shift cam for signs of

excessive wear. Check the pins on the shift cam for wear and damage.

If undesirable conditions are found, replace the shift cam.

17 Check the shift forks for distortion and wear, especially at the fork

tips (see illustration 27.5 in Part A of this Chapter). If they are

discolored or severely worn they are probably bent. If damage or wear

is evident, check the shift fork groove in the corresponding gear as

well. Inspect the guide pins and the shaft bore for excessive wear and

distortion and replace any defective parts with new ones.

18 Check the shift fork guide bar for evidence of wear, galling and 
other damage. Make sure the shift forks move smoothly on the bar. If

the bar is worn or bent, replace it with a new one.

19 Check the stopper plate in the crankcase for looseness (see

illustration). If the plate is loose, remove its screws and apply thread

locking compound (Loctite Stud n Bearing Mount or equivalent) to the

threads. Reinstall the screws and tighten them to the torque listed in

this Chapters Specifications.

20 Check the bearing on the shift cam for looseness, noise or rough

movement. If its condition is in doubt, remove the cam plate to replace

the bearing (see illustration). Note: The cam plate screw may be very

tight. Use an impact driver to remove it Its a good idea to make sure

theres a replacement screw in stock at your local Yamaha dealer

before removing the old screw.

Assembly and installation

Refer to illustrations 26.21, 26.22, 26.25, 26.26, 26.27a and 26.27b

21 Assemble the transmission shafts by reversing the disassembly

steps. Install the snap-rings with the sharp edges toward the gears

theyre retaining, and their rounded edges away from the gears. Coat

all parts with clean engine oil during assembly. Position the ends of the

snap-rings correctly (see illustration).

22 Install the shift cam in the crankcase (see illustration 26.7).

Install the neutral switch (see Chapter 8) and engage the shift cam with

it (see illustration).

23 Mesh the gears on both transmission shafts and position the shift

fork on the fifth pinion gear. Use the numbers on the forks to position

26.20 Remove the cam plate if necessary

to remove the shift cam bearing 
26.21 Install the snap-rings with their

ends in the correct position 
26.22 Install the neutral switch, then turn

the shift cam to align with it 
						

							
Chapter 2 Part B Engine, clutch and transmission (XV700-1100 models)

2B-49

26.25 Engage the pin on the fifth pinion

gear shift fork with the groove in the

shift cam 
26.26 Install the remaining two shift forks

and engage their pins with the shift

cam grooves 
26.27a Slide the guide bar through

the forks ...

26.27b ... and align its flat with the teeth of the middle drive gear
them correctly. The forks are numbered from one to three, starting

from the left side of the engine.

24 Install the transmission shafts and fifth pinion gear shift fork as an

assembly (see illustration 26.6).

25 Engage the shift fork pin with the shift cam (see illustration).

26 Install the remaining two shift forks in their gear grooves and

engage their pins with the shift cam (see illustration).

27 Slide the shift fork guide bar through the forks (see illustration).

Turn the guide bar so its flat is aligned with the middle-drive gear teeth

(see illustration).

28 The remainder of installation is the reverse of the removal steps.

27 Initial start-up after overhaul

1 Make sure the engine oil level is correct, then remove the spark

plugs from the engine. Place the engine kill switch in the Off position

and unplug the primary (low tension) wires from the coils.

2 Turn on the key switch and crank the engine over with the starter

several times to build up oil pressure. Reinstall the spark plugs,

connect the wires and turn the switch to On.

3 Make sure there is fuel in the tank, then turn the fuel tap to the On

position and operate the choke.

4 Start the engine and allow it to run at a moderately fast idle until it

reaches operating temperature.

5 Check carefully for oil leaks and make sure the transmission and

controls, especially the brakes, function properly before road testing

the machine. Refer to Section 28 for the recommended break-in

procedure.

6 Upon completion of the road test, and after the engine has cooled

down completely, recheck the valve clearances (see Chapter 1).

28 Recommended break-in procedure

1 Any rebuilt engine needs time to break-in, even if parts have been

installed in their original locations. For this reason, treat the machine

gently for the first few miles to make sure oil has circulated throughout

the engine and any new parts installed have started to seat.

2 Even greater care is necessary if the engine has been rebored or a

new crankshaft has been installed. In the case of a rebore, the engine

will have to be broken in as if the machine were new. This means

greater use of the transmission and a restraining hand on the throttle 
until at least 500 miles (800 km) have been covered. Theres no point in

keeping to any set speed limit - the main idea is to keep from lugging

the engine and to gradually increase performance until the 500 mile

(800 km) mark is reached. These recommendations can be lessened to

an extent when only a new crankshaft is installed. Experience is the

best guide, since its easy to tell when an engine is running freely. The

following recommendations, which Yamaha provides for new

motorcycles, can be used as a guide:

a) 0 to 90 miles (0 to 150 km): Keep engine speed below 3,000 rpm.

Turn off the engine after each hour of operation and let it cool for

5 to 10 minutes. Vary the engine speed and dont use full throttle.

b) 90 to 300 miles (150 to 500 km): Dont run the engine for long

periods above 4,000 rpm. Rev the engine freely through the gears,

but dont use full throttle.

c) 300 to 600 miles (500 to 1000 km): Dont use full throttle for

prolonged periods and dont cruise at speeds above 5,000 rpm.

d) At 600 miles (1,000 km): Change the engine oil and filter. Full

throttle can be used after this point.

3 If a lubrication failure is suspected, stop the engine immediately

and try to find the cause. If an engine is run without oil, even for a short

period of time, severe damage will occur. 
						

							
2B-50 
Chapter 2 Part B Engine, clutch and transmission (XV700-1100 models)

Notes 
						

							
3A-1

Chapter 3 Part A

Fuel and exhaust systems (XV535 models)

Contents

Section

Air induction system (1990-on US models) -

inspection and component replacement 13

Air filter element - servicing See Chapter 1

Carburetor overhaul - general information 5

Carburetors and intake joints - removal and installation 6

Carburetors - disassembly, inspection, cleaning

and reassembly 7

Carburetors - fuel level adjustment 8

Evaporation control system (California models) - inspection

and canister replacement 14

Exhaust system - removal and installation 10

Fuel pump and relay - replacement 12 
Section

Fuel pump - circuit check and fuel pump test 11

Fuel reserve switch - test See Chapter 8

Fuel sender - replacement See Chapter 8

Fuel system - check and filter replacement See Chapter 1

Fuel tank - cleaning and repair 3

Fuel tank - removal and installation 2

General information 1

Idle fuel/air mixture adjustment - general information 4

Idle speed - check and adjustment See Chapter 1

Throttle cables and grip - removal, installation and adjustment.... 9

Throttle operation/grip freeplay - check

and adjustment See Chapter 1 
						

							
3A-2 
Chapter 3 Part A Fuel and exhaust systems (XV535 models)

Specifications

Carburetor

Type Mikuni BDS34 (two)

Jet sizes

Main jet

1987 and 1988 135

1989 through 1993

Front cylinder 137.5

Rear cylinder 135

1994 US

Front cylinder 137.5

Rear cylinder 135

1994 UK and Canada 135

Main air jet 140

Jet needle/clip position

1987 and 1988 US and Canada

Front cylinder 5DZ7-1

Rear cylinder 5DZ8-1

1990 through 1993 US and Canada

Front cylinder 5DZ17-1

Rear cylinder 5DZ18-1

1994 US

Front cylinder 5DZ17-1

Rear cylinder 5DZ18-1

1994 Canada

Front cylinder 5DZ9-3

Rear cylinder 5DZ10-3

All UK

Front cylinder 5DZ10-3

Rear cylinder 5DZ9-3

Main nozzle Y-0

Pilot air jet no. 1

1987 and 1988 US 60

All others 70

Pilot air jet no. 2

1987 and 1988 US 160

All others 170

Pilot jet

1987 and 1988 US 32.5

Ail others 35

Pilot screw

1987 and 1988 US Preset (not specified)

1990 through 1993 US and Canada 2-1/2 turns out

1994 US . 2-1/2 turns out

1994 Canada, all UK 2 turns out

Valve seat size 1.5

Starter jet

Except 1994 US 40

1994 US 35

Fuel level 13.5 to 14.5 mm (0.53 to 0.57 inch)

Fuel tank capacity

1987 and 1988 models 8.6 liters (2.3 US gal, 1.9 Imp gal), including reserve of

2.5 liters (0.7 US gal, 0.5 Imp gal)

1989-on models 13.5 liters (3.6 US gal, 3.0 Imp gal), including reserve of

2.5 liters (0.7 US gal, 0.5 Imp gal)

Tightening torques

Carburetor joint bolts 12 Nm (8.7 ft-lbs)

Exhaust pipe-to-cylinder head nuts 20 Nm (14 ft-lbs)

Exhaust pipe rear joint bolt 10 Nm (7.2ft-lbs)

Muffler/silencer chamber bolt and nut 20 Nm (14 ft-lbs) 
						

							
Chapter 3 Part A Fuel and exhaust systems (XV535 models) 
3A-3

2.4a Release the fuel hoses from the clips on top of the

battery cover

A Clips

B Hose clamps

C Tank mounting bolts 
D Battery positive cable

(always disconnect the

negative cable first)

2.4b Fuel tanks and lines (models with upper fuel tank)

1 Fuel lines

2 Fuel filter

3 Fuel pump 
4 Fuel tap

5 Lower fuel tank

6 Upper fuel tank

2.5a Remove the upper tank mounting bolt at the rear ...

2.5b ... and one on each side
1 General information

The fuel system consists of the fuel tank, the fuel tap and filter,

the carburetors and the connecting lines, hoses and control cables and

an electric fuel pump.

The carburetors used on these motorcycles are two Mikunis with

butterfly-type throttle valves. For cold starting, an enrichment circuit is

actuated by a choke lever mounted on the left side of the bike.

The exhaust system routes exhaust gases into a muffler/silencer

chamber under the bike and then into twin exhaust pipes on the right

side.

Many of the fuel system service procedures are considered routine

maintenance items and for that reason are included in Chapter 1.

2 Fuel tank - removal and installation

Warning: Gasoline (petrol) is extremely flammable, so take extra

precautions when you work on any part of the fuel system. Dont smoke

or allow open flames or bare light bulbs near the work area, and dont

work in a garage where a natural gas-type appliance (such as a water

heater or clothes dryer) is present. If you spill any fuel on your skin,

rinse it off immediately with soap and water. When you perform any

kind of work on the fuel system, wear safety glasses and have a fire

extinguisher suitable for class B fires (flammable liquids) on hand. 
1 All models have a main fuel tank mounted beneath the seat. Later

models also have an upper fuel tank mounted forward of the seat on

top of the upper frame section in the traditional position (on early

models, what looks like a fuel tank is actually a cover).

2 Support the bike securely so it cant be knocked over during this

procedure.

3 Remove the seat (see Chapter 7).

Upper fuel tank

Refer to illustrations 2.4a, 2.4b, 2.5a, 2.5b, 2.6a and 2.6b

4 Free the fuel hoses from the clips on top of the battery cover,

remove the cover and disconnect the negative cable from the battery

(see illustrations).

5 Remove the upper tank mounting bolts and washers (see

illustrations). Remove the metal collars from inside the left and right

rubber dampers, then remove all three dampers. 
						

							
3A-4 
Chapter 3 Part A Fuel and exhaust systems (XV535 models)

2.6a Lift the tank and disconnect the

hoses from the fittings (arrows) . . . 
2.6b ... theres a fuel hose on each side

2.10 Remove the mounting bolts (arrows)

and take off the footpeg bracket

2.11 Fuel tank and lines (models without upper fuel tank)

1 Vapor hoses

2 Breather hose

3 Rollover valve

4 Fuel filter 
5 Fuel pump

6 Fuel tank

7 Rubber cover 
2.13 Work the drain fitting (arrow) free of the rubber cover and lift

the cover out

6 Hold a pan under the fittings to catch drained fuel, lift the upper

tank and disconnect the fuel hoses (see illustrations). Liff the tank off

the bike. Warning: Pour the drained fuel into a safe fuel storage

container. Dont leave it in the drain pan.

Main fuel tank

Refer to illustrations 2.10,2.11, 2.13, 2.14a and 2.14b

7 If youre working on a bike with an upper fuel tank, remove it.

Disconnect the upper tank hoses from their fittings on the main tank

(see illustrations 2.4a and 2.4b).

8 Remove the left side cover (see Chapter 7).

9 If youre working on a bike without an upper fuel tank, remove the

fuel filler cap. 
10 Remove the left passenger footpeg bracket (see illustration).

11 Remove the fuel filter (see Chapter 1 and the accompanying

illustration).

12 Disconnect the fuel pump electrical connector and the line that

runs from the pump to the carburetors (see Section 12). If you plan to

remove the fuel pump, this is a good time to do it; if not, it can be left

attached to the tank.-

13 If youre working on a bike without an upper fuel tank, remove the

rubber cover from the top of the main tank (see illustration).

14 Remove the tank mounting bolts and disengage the rubber

dampers from the brackets (see illustrations).

15 Check to make sure all hoses and wires have been disconnected,

then remove the tank through the left side of the frame.

All models

16 Before installing the tank, check the condition of the hoses

and rubber mounting dampers - if theyre hardened, cracked, or show

any other signs of deterioration, replace them.

17 When replacing the tank, reverse the above procedure. Make sure

the tank seats properly and does not pinch any control cables or wires.

3 Fuel tank - cleaning and repair

1 All repairs to the fuel tank should be carried out by a professional

who has experience in this critical and potentially dangerous work. 
						

							
Chapter 3 Part A Fuel and exhaust systems (XV535 models)

3A-5

2.14a Remove the mounting bolts ... 
2.14b ... and detach the rubber dampers

from the brackets 
6.6 Free the hose from the retaining clips

Even after cleaning and flushing of the fuel system, explosive fumes

can remain and ignite during repair of the tank.

2 If the fuel tank is removed from the vehicle, it should not be

placed in an area where sparks or open flames could ignite the fumes

coming out of the tank. Be especially careful inside garages where a

natural gas-type appliance is located, because the pilot light could

cause an explosion.

4 Idle fuel/air mixture adjustment - general information

1 Due to the increased emphasis on controlling motorcycle exhaust

emissions, certain governmental regulations have been formulated

which directly affect the carburetion of this machine. In order to

comply with the regulations, the carburetors on some models have a

metal sealing plug pressed into the hole over the pilot screw (which

controls the idle fuel/air mixture) on each carburetor, so they cant be

tampered with. These should only be removed in the event of a

complete carburetor overhaul, and even then the screws should be

returned to their original settings. The pilot screws on other models are

accessible, but the use of an exhaust gas analyzer is the only accurate

way to adjust the idle fuel/air mixture and be sure the machine doesnt

exceed the emissions regulations.

2 If the engine runs extremely rough or blows black smoke at idle or

continually stalls, and if a carburetor overhaul does not cure the

problem, take the motorcycle to a Yamaha dealer service department

or other repair shop equipped with an exhaust gas analyzer. They will

be able to properly adjust the idle fuel/air mixture to achieve a smooth

idle and restore low speed performance.

5 Carburetor overhaul - general information

1 Poor engine performance, hesitation, hard starting, stalling,

flooding and backfiring are all signs that major carburetor maintenance

may be required.

2 Keep in mind that many so-called carburetor problems are really

not carburetor problems at all, but mechanical problems within the

engine or ignition system malfunctions. Try to establish for certain that

the carburetors are in need of maintenance before beginning a major

overhaul.

3 Check the fuel filter, the fuel lines, the fuel tank breather hose(s),

the rollover valve (models with evaporative emission control), the

intake manifold hose clamps, the vacuum hoses, the air filter element,

the cylinder compression, the spark plugs, the carburetor synchro-

nization and the fuel pump before assuming that a carburetor overhaul

is required.

4 Most carburetor problems are caused by dirt particles, varnish 
and other deposits which build up in and block the fuel and air

passages. Also, in time, gaskets and O-rings shrink or deteriorate and

cause fuel and air leaks which lead to poor performance.

5 When the carburetor is overhauled, it is generally disassembled

completely and the parts are cleaned thoroughly with a carburetor

cleaning-solvent and dried with filtered, unlubricated compressed air.

The fuel and air passages are also blown through with compressed air

to force out any dirt that may have been loosened but not removed by

the solvent. Once the cleaning process is complete, the carburetor is

reassembled using new gaskets, O-rings and, generally, a new inlet

needle valve and seat.

6 Before disassembling the carburetors, make sure you have a

carburetor rebuild kit (which will include all necessary O-rings and

other parts), some carburetor cleaner, a supply of rags, some means of

blowing out the carburetor passages and a clean place to work. It is

recommended that only one carburetor be overhauled at a time to

avoid mixing up parts.

7 Dont separate the carburetors from each other unless one of the

joints between them is leaking. The carburetors can be overhauled

completely without being separated, and reconnecting them properly

can be difficult.

6 Carburetors and intake joints - removal and

installation

Warning: Gasoline (petrol) is extremely flammable, so take extra

precautions when you work on any part of the fuel system. Dont smoke

or allow open flames or bare light bulbs near the work area, and dont

work in a garage where a natural gas-type appliance (such as a water

heater or clothes dryer) is present. If you spill any fuel on your skin,

rinse it off immediately with soap and water. When you perform any

kind of work on the fuel system, wear safety glasses and have an

extinguisher suitable for class B fires (flammable liquids) on hand.

Removal

Refer to illustrations 6.6, 6.8, 6.9, 6.10a, 6.10b, 6.11a, 6.11b, 6.11c,

6.13a and 6.13b

1 Remove the seat (see Chapter 7).

2 If youre working on a model with an upper fuel tank, remove it

(see Section 2).

3 If youre working on a model without an upper fuel tank, remove

the top cover (see Chapter 7).

4 Remove the left front side cover and its bracket (see Chapter 7).

5 . Remove the right front side cover and the electrical component

board beneath it (see Chapter 7).

6 Work the hose on the right side free of the clips (see illustration).

7 Disconnect the throttle cable from the pulley (see Section 9).