Haynes Yamaha Xv V Twins Manual

							
2A-16

Chapter 2 Part A Engine, clutch and transmission (XV535 models)

8.42a Install new sealing washers on the

rocker shaft bolts 
8.42b Use a screwdriver to position the

rocker shafts so the bolts will line up

with them 
8.42c Install the bolts with their sealing

washers and tighten them to the torque

listed in this Chapters Specifications

8.44a Slip the O-ring onto the

large dowel.. 
8.44b ... and install the large dowel and

two small dowels in their bores ... 
8.44c ... and install the head gasket over

the studs and dowels

8.45 Install the exhaust side cam chain

damper in its slot with the UP mark

(arrow) up 
8.46a As you lower the head onto the

studs, move the cam chain and damper

aside so they dont obstruct installation of

the head 
8.46b Slip the exhaust side chain damper

into its notch (arrow) as the head is

lowered into position

Chapters Specifications, then bend the lockwasher tabs against the

bolt heads.

42 Install new sealing washers on the rocker arm holding bolts (see

illustration). Use a screwdriver to position the ends of the rocker

shafts so the bolts will align with them (see illustration), then install

the bolts with their sealing washers and tighten them to the torque

listed in this Chapters Specifications (see illustration). 
Cylinder head installation

Rear cylinder head

Refer to illustrations 8.44a, 8.44b, 8.44c, 8.45, 8.46a, 8.46b, 8.47a,

8.47b, 8.47c, 8.47d,8.50, 8.57a, 8.57b, 8.57c and 8.57d

43 If both cylinder heads have been removed, install the rear cylinder

head first.  
						

							
Chapter 2 Part A Engine, clutch and transmission (XV535 models)

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8.47a install the engine mounting bracket on the right side of the

rear cylinder head ... 
8.47b ... install the cylinder head cover bracket next and thread

two of the short nuts onto the studs on top of the

cover bracket...

8.47c ... On the left side of the engine, install the engine

mounting bracket (A) and two thin washers (B), then install two

short nuts ...

8.50 Fit the cam sprocket into the chain so its dowel hole will

align with the camshaft dowel

44 Install the O-ring on the large dowel and install the two smaller

dowels, then install the new head gasket on top of the cylinder (see

illustrations). Never reuse the old head gasket and dont use any type

oil gasket sealant.

45 Install the cam chain damper on the exhaust side (if removed)

with its UP mark up (see illustration).

46 Position the cylinder head on the studs and guide the cam chain

damper through the slot in the cylinder head (see illustration). Be sure 
8.47d ... the installed brackets should look like this

the upper end of the cam chain damper fits into the. notch in the

bottom of the cylinder head (see illustration).

47 Install the cylinder head bolts and nuts together with the engine

mounting brackets and cylinder head cover bracket (see illustrations).

Four of the shorter nuts go on the rear cylinder head; the longer nuts

and the remaining four short nuts go on the front cylinder head.

Tighten the bolts and nuts evenly in several stages, in a criss-cross

pattern, to the torque listed in this Chapters Specifications.

48 Make sure the camshaft locating dowel is aligned with the mark

on the cylinder head (see illustration 8.13).

49 If youre working on the rear cylinder head, make sure the line on

the timing rotor with a T mark next to it aligns with the notch in the

timing window (see illustration 8.6a). If its necessary to turn the

crankshaft, hold the timing chain up while youre turning so it doesnt

fall off the crankshaft sprocket and become jammed.

50 Engage the camshaft sprocket with the timing chain so its dowel

hole aligns with the dowel (see illustration). Slip the sprocket onto the

camshaft over the dowel.

51 Install the oil baffle plate with its concave side out, away from the

sprocket (see illustration 8.11).

52 Turn the cam sprocket clockwise far enough to remove all slack in

the cam chain, but no farther. Insert a finger in the tensioner hole and

push against the chain damper. Make sure the timing marks on the

cam sprocket and crankshaft are aligned correctly (see illustrations

8:6a and 8.6b).

53 With the marks correctly aligned, tighten the cam sprocket bolt to

the torque listed in this Chapters Specifications.

54 Install the cam chain tensioner (see Section 7). 
						

							
2A-18 
Chapter 2 Part A Engine, clutch and transmission (XV535 models)

8.57a Install a new O-ring on the cam

sprocket cover . .. 
8.57b ... and one on the oil baffle plate 
8.57c Align the hole in the oil baffle plate

with the locating pin in the

cover (arrows)...

8.57d ... then press the plate into the

cover and install a new gasket 
8.58a The line without a T mark next to it

must be aligned with the notch in the

timing window ...

55 Adjust the valve clearances (see Chapter 1).

56 Install the rocker arm covers with new O-rings. Install the intake

rocker arm cover with its ridge up (see Valve clearance - adjustment in

Chapter 1).

57 Install the oil baffle and cam sprocket cover, using new O-rings

(see illustrations).

Front cylinder head

Refer to illustrations 8.58a, 8.58b and 8.59a through 8.59e

58 Repeat Steps 44 through 46 to install the front cylinder head,

noting that the slot in the timing rotor must be aligned with the

crankcase pointer when the camshaft dowel is aligned with the

cylinder head mark (see illustrations).

59 Install the washers, cylinder head nuts and bolts and engine

mounting bracket (see illustrations).

60 Repeat Steps 48 through 57 to finish installing the cylinder head,

noting that there is no oil baffle on the sprocket or in the cam sprocket

cover.

61 Install the ignition coils and their bracket (see Chapter 4).

Both cylinder heads

62 Change the engine oil (see Chapter 1).

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

9 Valves/valve seats/valve guides - servicing

1 Because of the complex nature of this job and the special tools

and equipment required, servicing of the valves, the valve seats and 
the valve guides (commonly known as a valve job) is best left to a

professional.

2 The home mechanic can, however, remove and disassemble the

head, do the initial cleaning and inspection, then reassemble and

deliver the head to a dealer service department or properly equipped

motorcycle repair shop for the actual valve servicing. Refer to Section

8 for those procedures.

3 The dealer service department will remove the valves and springs,

recondition or replace the valves and valve seats, replace the valve

guides, check and replace the valve springs, spring retainers and

keepers/collets (as necessary), replace the valve seals with new ones

and reassemble the valve components.

4 After the valve job has been performed, the head will be in like-

new condition. When the head is returned, be sure to clean it again

very thoroughly before-installation on the engine to remove any metal

particles or abrasive grit that may still be present from the valve service

operations. Use compressed air, if available, to blow out all the holes

and passages.

10 Cylinder head and valves - disassembly, inspection

and reassembly

1 As mentioned in the previous Section, valve servicing and valve

guide replacement should be left to a dealer service department or

motorcycle repair shop. However, disassembly, cleaning and

inspection of the valves and related components can be done (if the

necessary special tools are available) by the home mechanic. This way 
8.58b ... and the camshaft dowel must

be aligned with the pointer cast in the

cylinder head (arrows) 
						

							
Chapter 2 Part A Engine, clutch and transmission (XV535 models)

2A-19

8.59a On the left side of the front

cylinder head, install the cylinder head

cover bracket... 
8.59b ... install two washers on the

right side ... 
8.59c ... and install the four long nuts

(arrows) on top of the bracket and

washers (tighten the cylinder head nuts

and bolts at this point)

8.59d Install four thick washers over the long nuts ... 
8.59e ... install the mounting bracket, then install two thin

washers on the left studs; install the remaining four thin nuts and

tighten to the torque listed in this Chapters Specifications

10.7a Compress the valve springs with a spring compressor ...

no expense is incurred if the inspection reveals that service work is not

required at this time.

2 To properly disassemble the valve components without the risk of

damaging them, a valve spring compressor is absolutely necessary.

This special tool can usually be rented, but if its not available, have a

dealer service department or motorcycle repair shop handle the entire

process of disassembly, inspection, service or repair (if required) and

reassembly of the valves. 
Disassembly

Refer to illustrations 10.7a through 10.7g and 10.9

3 Remove the camshafts and rocker arms if you havent already

done so (see Section 8). Store the components in such a way that they

can be returned to their original locations without getting mixed up.

4 Before the valves are removed, scrape away any traces of gasket

material from the head gasket sealing surface. Work slowly and do not

nick or gouge the soft aluminum of the head. Gasket removing

solvents, which work very well, are available at most motorcycle shops

and auto parts stores.

5 Carefully scrape all carbon deposits out of the combustion

chamber area. A hand held wire brush or a piece of fine emery cloth

can be used once the majority of deposits have been scraped away.

Do not use a wire brush mounted in a drill motor, or one with extremely

stiff bristles, as the head material is soft and may be eroded away or

scratched by the wire brush.

6 Before proceeding, arrange to label and store the valves along

with their related components so they can be kept separate and

reinstalled in the same valve guides they are removed from (labeled

plastic bags work well for this).

7 Compress the valve spring on the first valve with a spring

compressor, then remove the keepers/collets and the upper spring

seat from the valve assembly (see illustrations). Do not compress the

springs any more than is absolutely necessary. Carefully release the

valve spring compressor and remove the spring and the valve from the 
						

							
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Chapter 2 Part A Engine, clutch and transmission (XV535 models)

10.7b ... until the keepers/collets

are exposed 
10.7c Remove the keepers/collets with

a magnet 
10.7d Release the spring pressure and

remove the spring retainer ...

10.7e ... and the springs

10.7f Pull the valve into the combustion

chamber, but dont force it 
10.7g If the valve binds in the guide,

deburr the area above the keeper groove

10.9 Pull the valve stem seal (arrow) off the valve guide

head (see illustration), if the valve binds in the guide (wont pull

through), push it back into the head and deburr the area around the

keeper/collet groove with a very fine file or whetstone (see

illustration).

8 Repeat the procedure for the remaining valves. Remember to

keep the parts for each valve together so they can be reinstalled in the

same location. 
9 Once the valves have been removed and labeled, pull off the

valve stem seals (see illustration) with pliers and discard them (the old

seals should never be reused), then remove the lower spring seats.

10 Next, clean the cylinder head with solvent and dry it thoroughly.

Compressed air will speed the drying process and ensure that all holes

and recessed areas are clean.

11 Clean all of the valve springs, keepers/collets, retainers and

spring seats with solvent and dry them thoroughly. Do the parts from

one valve at a time so that no mixing of parts between valves occurs.

12 Scrape off any deposits that may have formed on the valve, then

use a motorized wire brush to remove deposits from the valve heads

and stems. Again, make sure the valves do not get mixed up.

Inspection

Refer to illustrations 10.14, 10.16, 10.17, 10.18a, 10.18b 10 19aand

10.19b

13 Inspect the head very carefully for cracks and other damage. If

cracks are found, a new head will be required. Check the cam bushing

surfaces for wear and evidence of seizure. Check the camshafts and

rocker arms for wear as well (see Section 9).

14 Using a precision straightedge and a feeler gauge, check the

head gasket mating surface for warpage (see illustration). Lay the

straightedge lengthwise, across the head and diagonally (corner-to-

corner), intersecting the head bolt holes, and try to slip a feeler gauge

under it, on either side of each combustion chamber. The gauge

should be the same thickness as the cylinder head warp limit listed in

this Chapters Specifications. If the feeler gauge can be inserted

between the head and the straightedge, the head is warped and must 
						

							
Chapter 2 Part A Engine, clutch and transmission (XV535 models)

2A-21

10.14 Check the cylinder head for warpage with a straightedge

and feeler gauge

10.16 Measure the valve guide inside diameter with a small hole

gauge, then measure the hole gauge with a micrometer

10.17 Check the valve face (A), stem (B) and keeper/collet groove

(C) for signs of wear and damage

10.18a Measure the valve stem diameter with a micrometer

10.18b Check the valve stem for bends with a V-block (or blocks,

as shown here) and a dial indicator

either be machined or, if warpage is excessive, replaced with a new

one. Minor surface imperfections can be cleaned up by sanding on a

surface plate in a figure-eight pattern with 400 or 600 grit wet or dry

sandpaper. Be sure to rotate the head every few strokes to avoid

removing material unevenly.

15 Examine the valve seats in each of the combustion chambers. If

they are pitted, cracked or burned, the head will require valve service

thats beyond the scope of the home mechanic. Measure the valve

seat width and compare it to this Chapters Specifications. If it is not 
within the specified range, or if it varies around its circumference, valve

service work is required.

16 Clean the valve guides to remove any carbon buildup, then

measure the inside diameters of the guides (at both ends and the

center of the guide) with a small hole gauge and a 0-to-1-inch

micrometer (see illustration). Record the measurements for future

reference. These measurements, along with the valve stem diameter

measurements, will enable you to compute the valve stem-to-guide

clearance. This clearance, when compared to the Specifications, will

be one factor that will determine the extent of the valve service work

required. The guides are measured at the ends and at the center to

determine if they are worn in a bell-mouth pattern (more wear at the

ends). If they are, guide replacement is an absolute must.

17 Carefully inspect each valve face for cracks, pits and burned

spots. Check the valve stem and the keeper/collet groove area for

cracks (see illustration). Rotate the valve and check for any obvious

indication that it is bent. Check the end of the stem for pitting and

excessive wear and make sure the bevel is the specified width. The

presence of any of the above conditions indicates the need for valve

servicing.

18 Measure the valve stem diameter (see illustration). By

subtracting the stem diameter from the valve guide diameter, the valve

stem-to-guide clearance is obtained. If the stem-to-guide clearance is

greater than listed in this Chapters Specifications, the guides and

valves will have to be replaced with new ones. Also check the valve

stem for bending. Set the valve in a V-block with a dial indicator

touching the middle of the stem (see illustration). Rotate the valve and 
						

							
2A-22 
Chapter 2 Part A Engine, clutch and transmission (XV535 models)

10.19a Measure the free length of the

valve springs 
10.19b Check the valve springs

for squareness 
10.23 Apply the lapping compound very

sparingly, in small dabs, to the valve

face only

10.24 After lapping, the valve face should

have a uniform, unbroken contact

pattern (arrow) 
10.28a A small dab of grease will hold the

keepers/collets in place on the valve while

the spring is released 
10.28b With the keepers/collets secure

in their grooves (arrow), release the

spring compressor

note the reading on the gauge. If the stem runout exceeds the value

listed in this Chapters Specifications, replace the valve.

19 Check the end of each valve spring for wear and pitting. Measure

the free length (see illustration) and compare it to this Chapters

Specifications. Any springs that are shorter than specified have

sagged and should not be reused. Stand the spring on a flat surface

and check it for squareness (see illustration).

20 Check the spring retainers and keepers/collets for obvious wear

and cracks. Any questionable parts should not be reused, as extensive

damage will occur in the event of failure during engine operation.

21 If the inspection indicates that no service work is required, the

valve components can be reinstalled in the head.

Reassembly

Refer to illustrations 10.23, 10.24, 10.28a and 10.28b

22 Before installing the valves in the head, they should be lapped to

ensure a positive seal between the valves and seats. This procedure

requires coarse and fine valve lapping compound (available at auto

parts stores) and a valve lapping tool. If a lapping tool is not available,

a piece of rubber or plastic hose can be slipped over the valve stem

(after the valve has been installed in the guide) and used to turn the

valve.

23 Apply a small amount of coarse lapping compound to the valve

face (see illustration), then slip the valve into the guide. Note: Make

sure the valve is installed in the correct guide and be careful not to get

any lapping compound on the valve stem.

24 Attach the lapping tool (or hose) to the valve and rotate the tool 
between the palms of your hands. Use a back-and-forth motion rather

than a circular motion. Lift the valve off the seat and turn it at regular

intervals to distribute the lapping compound properly. Continue the

lapping procedure until the valve face and seat contact area is of

uniform width and unbroken around the entire circumference of the

valve face and seat (see illustration).

25 Carefully remove the valve from the guide and wipe off all traces

of lapping compound. Use solvent to clean the valve and Wipe the seat

area thoroughly with a solvent soaked cloth.

26 Repeat the procedure with fine valve lapping compound, then

repeat the entire procedure for the remaining valves.

27 Lay the spring seats in place in the cylinder head, then install new

valve stem seals on each of the guides (see illustration 10.9). Use an

appropriate size deep socket to push the seals into place until they are

properly seated. Dont twist or cock them, or they will not seal properly

against the valve stems. Also, dont remove them again or they will be

damaged.

28 Coat the valve stems with assembly lube or moly-based grease,

then install one of them into its guide. Next, install the springs and

retainers, compress the springs and install the keepers/collets. Note:

Install the springs with the tightly wound coils at the bottom (next to the

spring seat). When compressing the springs with the valve spring

compressor, depress them only as far as is absolutely necessary to

slip the keepers/collets into place. Apply a small amount of grease to

the keepers/collets (see illustration) to help hold them in place as the

pressure is released from the springs. Make certain that the

keepers/collets are securely locked in their retaining grooves (see

illustration). 
						

							
Chapter 2 Part A Engine, clutch and transmission (XV535 models)

2A-23

11.2 Remove the single Allen bolt that

secures the cylinder to the crankcase 
11.3a Lift the cylinder straight up off

the studs 
11.3b Note the locations of the three

dowels (arrows); the large dowel has

an O-ring

11.4 Remove the O-ring from the base of the cylinder 
11.7 Measure the cylinder bore at the specified distance from the

top of the cylinder (1); measure parallel to the crankshaft

centerline, then at right angles to it

29 Support the cylinder head on blocks so the valves cant contact

the workbench top, then very gently tap each of the valve stems with a

soft-faced hammer. This will help seat the keepers/collets in their

grooves.

30 Once all of the valves have been installed in the head, check for

proper valve sealing by pouring a small amount of solvent into each of

the valve ports. If thesolvent leaks past the valve(s) into the

combustion chamber area, disassemble the valve(s) and repeat the

lapping procedure, then reinstall the valve(s) and repeat the check.

Repeat the procedure until a satisfactory seal is obtained.

11 Cylinders - removal, inspection and installation

Removal

Refer to illustrations 11.2, 11.3a, 11.3b and 11.4

1 Following the procedure given in Section 8, remove the cylinder

head.

2 Remove the cylinder bolt (see illustration).

3 Lift the cylinder straight up to remove it (see illustration). If its

stuck, tap around its perimeter with a soft-faced hammer, taking care

not to break the cooling fins. Dont attempt to pry between the cylinder

and the crankcase, as you will ruin the sealing surfaces. As you lift,

note the location of the dowel pins and O-ring (see illustration). Be

careful not to let these drop into the engine. 
4 Stuff clean shop towels around the pistons and remove the

gasket (see illustration) and all traces of old gasket material from the

surfaces of the cylinder, cylinder head and crankcase. Remove the O-

ring from the base of the cylinder (see illustration).

Inspection

Refer to illustrations 11.7 and 11.10

5 Dont attempt to separate the liner from the cylinder.

6 Check the cylinder wall carefully for scratches and score marks.

7 Using the appropriate precision measuring tools, check each

cylinders diameter. Measure parallel to the crankshaft axis and across

the crankshaft axis, at the depth from the top of the cylinder listed in

this Chapters Specifications (see illustration). Average the two

measurements and compare the results to this Chapters Specifi-

cations. If the cylinder walls are tapered, out-of-round, worn beyond

the specified limits, or badly scuffed or scored, have them rebored and

honed by a dealer service department or a motorcycle repair shop. If a

rebore is done, oversize pistons and rings will be required as well.

8 As an alternative, if the precision measuring tools are not

available, a dealer service department or motorcycle repair shop will

make the measurements and offer-advice concerning servicing of the

cylinders.

9 If they are in reasonably good condition and not worn to the

outside of the limits, and if the piston-to-cylinder clearances can be

maintained properly (see Section 12), then the cylinders do not have to

be rebored; honing is all that is necessary. 
						

							
2A-24

Chapter 2 Part A Engine, clutch and transmission (XV535 models)

11.10 Move the hone rapidly up-and-down without stopping

11.13a Place the cylinder base gasket

in position

11.13b Make sure the two small dowel pins are in position and

install the large dowel pin with its O-ring 
11.15 If youre experienced and very careful, you can install the

cylinder over the piston rings without a compressor, but a

compressor will make the job easier

10 To perform the honing operation you will need the proper size

flexible hone with fine stones, or a bottle brush type hone, plenty of

light oil or honing oil, some shop towels and an electric drill motor.

Hold the cylinder block in a vise (cushioned with soft jaws or wood

blocks) when performing the honing operation. Mount the hone in the

drill motor, compress the stones and slip the hone into the cylinder.

Lubricate the cylinder thoroughly, turn on the drill and move the hone

up and down in the cylinder at a pace which will produce a fine

Crosshatch pattern on the cylinder wall with the Crosshatch lines

intersecting at approximately a 60-degree angle (see illustration). Be

sure to use plenty of lubricant and do not take off any more material

than is absolutely necessary to produce the desired effect. Do not

withdraw the hone from the cylinder while it is running. Instead, shut

off the drill and continue moving the hone up and down in the cylinder

until it comes to a complete stop, then compress the stones and

withdraw the hone. Wipe the oil out of the cylinder and repeat the

procedure on the remaining cylinder. Remember, do not remove too

much materialfrom the cylinder wall. If you do not have the tools, or do

not desire to perform the honing operation, a dealer service

department or motorcycle repair shop will generally do it for a

reasonable fee.

11 Next, the cylinders must be thoroughly washed with warm soapy

water to remove all traces of the abrasive grit produced during the

honing operation. Be sure to run a brush through the bolt holes and

flush them with running water. After rinsing, dry the cylinders

thoroughly and apply a coat of light, rust-preventative oil to all

machined surfaces. 
Installation

Refer to illustrations 11.13a, 11.13b and 11.15

12 Lubricate the cylinder bore and piston with plenty of clean engine

oil.

13 Install a new O-ring around the base of the cylinder (see

illustration 11.4b). Place a new cylinder base gasket on the crankcase

(see illustration). Install a new O-ring on the large dowel pin, install it

in its bore and make sure the two small dowel pins are in position (see

illustration).

14 Attach a piston ring compressor to the piston and compress the

piston rings. A large hose clamp can be used instead - just make sure

it doesnt scratch the piston, and dont tighten it too much.

15 Install the cylinder block over the pistons and carefully lower it

down until the piston crown fits into the cylinder liner (see illustration).

While doing this, pull the camshaft chain up, using a hooked tool or a

piece of coat hanger. Also keep an eye on the cam chain guide to

make sure it doesnt wedge against the cylinder. Push down on the

cylinder, making sure the piston doesnt get cocked sideways, until the

bottom of the cylinder liner slides down past the piston rings. A wood

or plastic hammer handle can be used to gently tap the cylinder down,

but dont use too much force or the piston will be damaged.

16 Remove the piston ring compressor or hose clamp, being careful

not to scratch the piston.

17 Repeat the procedure to install the remaining cylinder.

18 The remainder of installation is the reverse of removal. 
						

							
Chapter 2 Part A Engine, clutch and transmission (XV535 models)

2A-25

12 Pistons - removal, inspection and installation

1 The pistons are attached to the connecting rods with piston pins

that are a slip fit in the pistons and rods.

2 Before removing the pistons from the rods, Stuff a clean shop

towel into each crankcase hole, around the connecting rods. This will

prevent the circlips from falling into the crankcase if they are inadver-

tently dropped.

Removal

Refer to illustrations 12.3a, 12.3b, 12.3c, 12.4a and 12.4b

3 Using a sharp scribe, scratch the location of each piston (front or 
rear cylinder) into its crown (or use a felt pen if the piston is clean

enough). Each piston should also have an EX mark on its crown; this

mark faces the exhaust side of the cylinder when the piston is installed

(see illustration). If not, scribe an arrow into the piston crown before

removal. Support the first piston, grasp the circlipwith a pointed tool

or needle-nose pliers and remove it from the groove (see

illustrations).

4 Push the piston pin out from the opposite end to free the piston

from the rod (see illustration). You may have to deburr the area

around the groove to enable the pin to slide out (use a triangular file for

this procedure). If the pin wont come out, remove the remaining

circlip. Fabricate a piston pin removal tool from threaded stock, nuts,

washers and a piece of pipe (see illustration). Repeat the procedure

for the other piston. 
2A

12.3c Connecting rods and pistons (XV535 models)

exploded view

1} Piston rings

2) Piston

3) Connecting rod bearings

4) Connecting rod

5) Crankshaft

6) Woodruff key (for alternator rotor)
12.3b Wear eye protection while pulling the circlips out; reach

into the removal notch with needle-nosed pliers to grasp

the circlip
12.3a The EX mark on top of the piston faces the exhaust side of

the cylinder (front side of the front cylinder, rear side of the

rear cylinder)