Main Shaft Inspection

WARNING: This page is about a different variant/trim than selected.

Check clearance "a" between synchronizer ring and gear, key slot width "b" in synchronizer ring and each chamfered tooth of gear and synchronizer ring and replace with new one, if necessary. Also, check gear tooth.
Clearance "a" between synchronizer ring and gear (main shaft)

Standard: 1.0 - 2.0 mm (0.039 - 0.079 in.)

Limit: 0.8 mm (0.031 in.)

Key slot width "b" (main shaft)

Fig 1: Key Slot Width Specification Chart
Courtesy of SUZUKI OF AMERICA CORP.

Fig 2: Identifying Key Slot Width And Clearance Between Synchronizer Ring And Gear
Courtesy of SUZUKI OF AMERICA CORP.
Check clearance between fork and sleeve. If clearance exceeds limit, replace fork and sleeve.
Clearance between fork and sleeve

Standard: 0.15 - 0.35 mm (0.006 - 0.014 in.)

Limit: 1.0 mm (0.039 in.)

Fig 3: Checking Clearance Between Fork And Sleeve
Courtesy of SUZUKI OF AMERICA CORP.
Check diameter of main shaft (1) / needle bush (2) and thickness of main shaft (1) / needle bush (2) flanges as shown in the figure. If measured value is out of specification, replace them (or it).
Main shaft / needle bush specification (diameter and thickness)

Fig 4: Main Shaft/Needle Bush Specification Chart
Courtesy of SUZUKI OF AMERICA CORP.
Using "V" blocks (1) and dial gauge (2), check runout. If runout exceeds limit, replace main shaft (3).
Main shaft runout

Limit: 0.06 mm (0.0024 in.)

Fig 5: Checking Runout Of Mainshaft
Courtesy of SUZUKI OF AMERICA CORP.
Using cylinder gauge (1), check inside diameter of each gear. If its inside diameter exceeds specification, replace it.
Inside diameter of gear (1st, 2nd and 3rd)

Standard: 44.015 - 44.040 mm (1.7329 - 1.7339 in.)

Fig 6: Checking Inside Diameter Of Each Gear Using Cylinder Gauge
Courtesy of SUZUKI OF AMERICA CORP.
Check chamfered part of each sleeve for damage and excessive wear, and replace as necessary.
Check each synchronizer key and synchronizer spring and replace as necessary.
Check splined portions and replace parts if excessive wear is found.
Check 2nd gear (1) thrust clearance by using thickness gauge (2). If clearance is out of specification, repress-fit or replace defective part.
2nd gear thrust clearance

Standard: 0.10 - 0.25 mm (0.004 - 0.010 in.)

Fig 7: Measuring 2nd Gear Thrust Clearance Using Thickness Gauge
Courtesy of SUZUKI OF AMERICA CORP.
Check low gear (1) thrust clearance by using thickness gauge (2). If clearance is out of specification, repress-fit or replace main shaft bearing and 5th gear.
Low gear thrust clearance

Standard: 0.10 - 0.25 mm (0.004 - 0.010 in.)

Fig 8: Checking Low Gear Thrust Clearance Using Thickness Gauge
Courtesy of SUZUKI OF AMERICA CORP.