1999 YAMAHA YZF-R7 seats

ENGINE SPECIFICATIONS
SPEC

2 - 5
Timing chain
Model/number of links DID219FTH3/100 ----
Tensioning system Automatic ----
Valves, valve seats, valve guides
Valve clearance (cold)
Intake 0.20 ~ 0.25 mm (0.0079 ~ 0.0098 in) ----
Exhaust 0.25 ~ 0.30 mm (0.0098 ~ 0.0118 in) ----
Valve dimensions
Valve head diameter A
Intake 22.1 ~ 22.3 mm (0.8701 ~ 0.8780 in) ----
Exhaust 23.4 ~ 23.6 mm (0.9213 ~ 0.9291 in) ----
Valve face width B
Intake 0.54 ~ 1.57 mm (0.0213 ~ 0.0618 in) ----
Exhaust 0.88 ~ 1.87 mm (0.0346 ~ 0.0736 in) ----
Valve seat width C
Intake 0.7 ~ 0.9 mm (0.028 ~ 0.035 in) ----
Exhaust 0.7 ~ 0.9 mm (0.028 ~ 0.035 in) ----
Valve margin thickness D
Intake 0.9 ~ 1.2 mm (0.028 ~ 0.047 in) ----
Exhaust 1.0 ~ 1.3 mm (0.039 ~ 0.051 in) ----
Valve stem diameter
Intake 3.983 ~ 3.995 mm (0.1568 ~ 0.1573 in) 3.953 mm
(0.1556 in)
Exhaust 3.978 ~ 3.990 mm (0.1566 ~ 0.1571 in) 3.948 mm
(0.1544 in)
Valve guide inside diameter
Intake 4.000 ~ 4.012 mm (0.1575 ~ 0.1580 in) 4.05 mm
(0.1594 in)
Exhaust 4.000 ~ 4.012 mm (0.1575 ~ 0.1580 in) 4.05 mm
(0.1594 in)
Valve stem-to-valve guide clear-
ance
Intake 0.005 ~ 0.029 mm (0.0002 ~ 0.0011 in) 0.06 mm
(0.0024 in)
Exhaust 0.010 ~ 0.034 mm (0.0004 ~ 0.0013 in) 0.07 mm
(0.0028 in) Item Standard Limit
Head Diameter
B
Face WidthC
Seat Width
D
Margin ThicknessA

4 - 19
ENGCYLINDER HEAD
EB402102
REMOVING THE CYLINDER HEAD
1. Remove:
• cylinder head bolts
• cylinder head nuts
NOTE:
• Loosen each bolt and nut 1/2 of a turn
at a time, in stages and in a crisscross
pattern. After all of the bolts and nuts
are fully loosened, remove them.
• Loosen the bolts and nuts in decreas-
ing numerical order (refer to the num-
bers in the illustration).
EB402402
CHECKING THE CYLINDER HEAD
1. Eliminate:
• combustion chamber carbon deposits
(with a rounded scraper)
NOTE:
Do not use a sharp instrument to avoid
damaging or scratching:
• spark plug bore threads
• valve seats
2. Check:
• cylinder head
Damage/scratches ® Replace.
• cylinder head water jacket
Mineral deposits/rust ® Eliminate.

4 - 23
ENGVALVES AND VALVE SPRINGS
EB403100
REMOVING THE VALVES
The following procedure applies to all of
the valves and related components.
NOTE:
Before removing the internal parts of the
cylinder head (e.g., valves, valve
springs, valve seats), make sure that the
valves properly seal.
1. Remove:
• valve lifter 1
• valve pad 2
NOTE:
Make a note of the position of each
valve lifter and valve pad so that they
can be reinstalled in their original place.
2. Check:
• valve
(for leakage)
Leakage at the valve seat ® Check the
valve face, valve seat, and valve seat
width.
Refer to “CHECKING THE VALVE
SEATS”.
t t t t t t t t t t t t t t t t t t t t t t t t t t t
a. Pour a clean solvent a into the intake
and exhaust ports.
b. Check that the valves properly seal.
NOTE:
There should be no leakage at the valve
seat 1.
s s s s s s s s s s s s s s s s s s s s s s s s s s s

4 - 26
ENGVALVES AND VALVE SPRINGS
5. Measure:
• valve margin thickness a
Out of specification ® Replace the
valve.
6. Measure:
• valve stem runout
Out of specification ® Replace the
valve.
NOTE:
• When installing a new valve, always
replace the valve guide.
• If the valve is removed or replaced,
always replace the oil seal.
Valve margin thickness
Intake
0.9 ~ 1.2 mm
(0.028 ~ 0.047 in)
Exhaust
1.0 ~ 1.3 mm
(0.039 ~ 0.051 in)
Valve stem runout
0.01 mm (0.0004 in)
EB403410
CHECKING THE VALVE SEATS
The following procedure applies to all of
the valves and valve seats.
1. Eliminate:
• carbon deposits
(from the valve face and valve seat)
2. Check:
• valve seat
Pitting/wear ® Replace the cylinder
head.
3. Measure:
• valve seat width a
Out of specification ® Replace the cyl-
inder head.
Valve seat width
0.9 ~ 1.1 mm
(0.035 ~ 0.043 in)
: 1.6 mm (0.06 in)

4 - 69
ENGCONNECTING RODS AND PISTONS
c. Put a piece of Plastigaugeâ 1 on the
crankshaft pin.
d. Assemble the connecting rod halves.
NOTE:
• Do not move the connecting rod or
crankshaft until the clearance mea-
surement has been completed.
• Lubricate the bolt threads and nut
seats with MOLYKOTE
® G-n paste.
• Make sure that the “Y” mark c on the
connecting rod faces towards the left
side of the crankshaft.
• Make sure that the characters d on
both the connecting rod and connect-
ing rod cap are aligned.
e. Tighten the connecting rod nuts.
Refer to “INSTALLING THE PISTONS
AND CONNECTING RODS”.
f. Remove the connecting rod and big
end bearings.
Refer to “REMOVING THE CONNECT-
ING RODS AND PISTONS”.
g. Measure the compressed Plasti-
gauge
â width e on the crankshaft
pin.
If the crankshaft pin-to-big end bear-
ing clearance is out of specification,
select replacement big end bearings.
s s s s s s s s s s s s s s s s s s s s s s s s s s s

4 - 71
ENGCONNECTING RODS AND PISTONS
2. Install:
• piston 1
(onto the respective connecting rod 2)
• piston pin 3
• piston pin clip 4
NOTE:
• Apply engine oil onto the piston pin.
• Make sure that the “Y” mark a on the
connecting rod faces left when the
arrow mark b on the piston is pointing
up. Refer to the illustration.
• Reinstall each piston into its original
cylinder (numbering order starting
from the left: #1 to #4).
Piston head
New
3. Offset:
• piston ring end gaps
aTop ring
bLower oil ring rail
cUpper oil ring rail
d2nd ring
Intake side
4. Lubricate:
• piston
• piston rings
• cylinder
(with the recommended lubricant)
5. Lubricate:
• bolt threads
• nut seats
(with the recommended lubricant)
ACHTUNG:CAUTION:
MOLYKOTEâ “G-n” paste is a special
grease, which should not be applied to
any part other than those specified.
Recommended lubricant
Engine oil
Recommended lubricant
MOLYKOTE® G-n paste

5 - 3
COOL

EB502000
RADIATOR AND THERMOSTAT
Order Job/Part Q’ty Remarks
Removing the thermostat assembly
Remove the parts in the order listed.
Rider seat and fuel tank Refer to “SEATS” and “FUEL TANK” in
chapter 3.
Air filter case and rubber cover Refer to “AIR FILTER CASE AND IGNI-
TION COIL PLATE” in chapter 3.
Carburetor assembly Refer to “CARBURETORS” in chapter 6.
Coolant Drain.
Refer to “CHANGING THE COOLANT”
in chapter 3.
Fuel tank and air filter case cover Refer to “FUEL TANK AND AIR FIL-
TER” in chapter 3.
Air filter case Refer to “ELECTRONIC FUEL INJEC-
TION” in chapter 6.
1 Thermostat assembly 1
2 Thermostat assembly inlet hose 1
RADIATOR AND THERMOSTAT