Haynes Yamaha Xv V Twins Manual

3A-16

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

9.1 Loosen the throttle cable adjuster

locknuts and loosen the adjusters

(arrows) 
9.2 Remove the screw that secures the

throttle cables to the housing 
9.3a Slip the cable out of its groove .

9.3b ... and disengage the end from

the pulley 
9.4a Pull the end of the cable out of the

socket and slip the cable sideways

through the slot to disengage it... 
9.4b ... then slide the end of the cable

sideways out of the pulley

9 Throttle...

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

3A-17

10.2a Exhaust system (XV535 models) - exploded view

1 Exhaust pipe gaskets

2 Exhaust pipe-to-rear

joint gasket 
3 Joint pipe (rear cylinder)

4 Exhaust pipe assembly 
5 Support the muffler/silencer chamber with a jack and unbolt it

from the frame (see illustration). Lower the exhaust system away from

the bike and take it out.

6 Installation is the reverse of removal, with the following additions:

a) Use new gaskets at the cylinder...

3A-18

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

11.6 Connect the positive lead (1) of a

0-20 volt voltmeter to the red/white wire

terminal of the connector (2) and the

negative lead to ground/earth (3) 
11.10 Connect a short jumper wire (arrow)

between the red/white and blue/black

wire terminals 
11.11 Connect the voltmeter positive (1)

lead to the back of the blue-black wire

terminal (2) and the negative lead to

ground/earth (3)

11.13 Connect the voltmeter positive lead (1) to...

Chapter 3 Part A Fuel and exhaust systems (XV535 models) 
3A-19

11.14 Connect the terminals in the

harness side of the fuel sender connector

to each other with a short jumper wire 
12.2 Disconnect the wiring connector and

remove the fuel pump relay 
12.5 Loosen the fuel line clamps (A),

disconnect the connector (B), remove the

mounting bolts (C) and take the pump out;

loosen the clamp screw (D) to remove the

pump from its bracket

Start switch and note the voltmeter reading.

a) If the reading...

3A-20

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

13.3a Pipe connections at the cylinder

heads are secured by screw-type

hose clamps 
13.3b The pipes are attached to the

right side of the engine with two Allen

bolts (arrows) 
13.3c Hose-to-pipe connections are

secured by spring-type clamps

2 Check the hoses for loose connections, damage and deterio-

ration. Tighten or replace loose or damaged hoses.

3 To replace system components, remove the left side cover (see

Chapter 7)....

3B-1

Chapter 3 Part B

Fuel and exhaust systems (XV700-1100 models)

Contents

Section

Air filter element - servicing See Chapter 1

Air induction system (XV1000, XV1100 and 1988

and laterXV750) - inspection and component replacement.... 15

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

Choke cable - removal and installation 10...

3B-2 
Chapter 3 Part B Fuel and exhaust systems (XV700-1100 models)

Carburetors

Type Hitachi HSC40 (two)

Main jet 122

Main air jet 50

Jet needle (US models)

Rear cylinder . Y-23

Front cylinder .... Y-22

Jet needle (UK models)

Rear cylinder Y-21

Front cylinder Y-20

Needle jet Not specified

Pilot air jet

US . 185

UK 180

Pilot jet . 41

Pilot screw Preset (turns out not specified)

Valve seat size 2.0

Starter jet 40

Fuel level

Rear cylinder 1.0 +/- 1.0 mm (0.039 +/-0.039 inch)

Front...

Chapter 3 Part B Fuel and exhaust systems (XV700-1100 models)

3B-3

Fuel level

Rear cylinder 1.0 +/-1.0 mm (0.039 +/- 0.039 inch)

Front cylinder :.. 2.0 +/-1.0 mm (0.078 +/- 0.039 inch)

Tightening torques

Carburetor joint bolts 10 Nm (7.2 ft-lbs)

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

XV920 chain drive models

Fuel tank capacity

Total ... 19 liters (5.02 US gal, 4.18 Imperial gal)

Reserve .... 3.2 liters (0.84 US gal, 0.70 Imperial gal)

Carburetors

Type Hitachi HSC40 (two)

Main...

3B-4 
Chapter 3 Part B Fuel and exhaust systems (XV700-1100 models)

Main jet .

Rear cylinder 126

Front cylinder 124

Main air jet 50

Jet needle

Rear cylinder Y-21

Front cylinder Y-20

Needle jet . Not specified

Pilot air jet 175

Pilot jet 43

Pilot screw .... Preset (turns out not specified)

Valve seat size 2.0

Starter jet . 40

Fuel level

Rear cylinder 1.0 +/-1.0 mm (0.039 +/- 0.039 inch)

Front cylinder 2.0 +/-1.0 mm (0.078 +/- 0.039 inch)

Tightening torques

Carburetor joint bolts 10 Nm...

Chapter 3 Part B Fuel and exhaust systems (XV700-1100 models)

3B-5

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.

XV1000 and XV1100 models use an electric fuel pump.

The carburetors used on these motorcycles are two Hitachis

(1981 through 1987) or Mikunis (1988 and later) with butterfly-type

throttle valves. For cold starting, an enrichment circuit is actuated by a

choke lever mounted...