User manual YAMAHA WR450 SERVICE MANUAL 2003

[. . . ] OWNER'S SERVICE MANUAL WR450FR LIT-11626-16-43 5TJ-28199-10 EC010000 WR450FR OWNER'S SERVICE MANUAL ©2002 by Yamaha Motor Corporation, U. S. A. 1st Edition, October 2002 All rights reserved. Any reprinting or unauthorized use without the written permission of Yamaha Motor Corporation U. S. A. LIT-11626-16-43 EC020000 INTRODUCTION Congratulations on your purchase of a Yamaha WR series. [. . . ] 3rd step: G Calculate the piston-to-cylinder clearance with following formula: Piston-to-cylinder clearance = Cylinder bore "C" ­ Piston skirt diameter "P" Piston-to-cylinder clearance: 0. 040 ~ 0. 065 mm (0. 0016 ~ 0. 0026 in) <Limit>: 0. 1 mm (0. 004 in) G If out of specification, replace the cylinder, and replace the piston and piston rings as set. 4 - 44 CYLINDER AND PISTON ENG Piston ring 1. Measure: G Ring side clearance Use a feeler gauge 1. Out of specification Replace the piston and rings as a set. NOTE: Clean carbon from the piston ring grooves and rings before measuring the side clearance. Side clearance: Standard Top ring 2nd ring 0. 030 ~ 0. 065 mm (0. 0012 ~ 0. 0026 in) 0. 020 ~ 0. 055 mm (0. 0008 ~ 0. 0022 in) <Limit> 0. 12 mm (0. 005 in) 0. 12 mm (0. 005 in) 2. Position: G Piston ring (in cylinder) NOTE: Insert a ring into the cylinder and push it approximately 10 mm (0. 39 in) into the cylinder. Push the ring with the piston crown so that the ring will be at a right angle to the cylinder bore. a 10 mm (0. 39 in) 3. Measure: G Ring end gap Out of specification Replace. NOTE: You cannot measure the end gap on the expander spacer of the oil control ring. If the oil control ring rails show excessive gap, replace all three rings. End gap: Standard Top ring 2nd ring Oil ring 0. 20 ~ 0. 30 mm (0. 008 ~ 0. 012 in) 0. 35 ~ 0. 50 mm (0. 014 ~ 0. 020 in) 0. 20 ~ 0. 50 mm (0. 01 ~ 0. 02 in) <Limit> 0. 55 mm (0. 022 in) 0. 85 mm (0. 033 in) -- 4 - 45 CYLINDER AND PISTON ENG Piston pin 1. Inspect: G Piston pin Blue discoloration/grooves Replace, then inspect the lubrication system. Measure: G Piston pin-to-piston clearance Measurement steps: G Measure the outside diameter (piston pin) a. If out of specification, replace the piston pin. Outside diameter (piston pin): 17. 991 ~ 18. 000 mm (0. 7083 ~ 0. 7087 in) G Measure the inside diameter (piston) b. Inside diameter (piston): 18. 004 ~ 18. 015 mm (0. 7088 ~ 0. 7093 in) G Calculate the piston pin-to-piston clearance with the following formula. Piston pin-to-piston clearance = Inside diameter (piston) b ­ Outside diameter (piston pin) a G If out of specification, replace the piston. Piston pin-to-piston clearance: 0. 004 ~ 0. 024 mm (0. 00016 ~ 0. 00094 in) <Limit>: 0. 07 mm (0. 003 in) ASSEMBLY AND INSTALLATION Piston 1. Install: G Piston rings Onto the piston. NOTE: G Be sure to install the piston rings so that the manufacturer's marks or numbers are located on the upper side of the rings. G Lubricate the piston and piston rings liberally with engine oil. 4 - 46 CYLINDER AND PISTON ad ENG 45° 135° 135° 2. Position: G Top ring G 2nd ring G Oil ring Offset the piston ring end gaps as shown. a Top ring end b 2nd ring end c Oil ring end (upper) d Oil ring e Oil ring end (lower) c be 3. Install: G Piston 1 G Piston pin 2 G Piston pin clips 3 New NOTE: G Apply engine oil onto the piston pin and piston. [. . . ] Turn adjuster counterclockwise (about 2 clicks) to decrease damping. Turn adjuster clockwise (about 2 clicks) to increase damping. Turn adjuster counterclockwise (about 2 clicks) to decrease damping. Set sunken length for 95 ~ 100 mm (3. 7 ~ 3. 9 in) when one passenger is astride seat (lower rear posture). [. . . ]