Main Shaft Inspection

Check clearance "a" between synchronizer ring and gear, width of index protrusion "b" in synchronizer ring, key slot width "c" in high and low speed synchronizer hub 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) (1st, 2nd and 3rd)
1. Standard: 0.65 - 1.75 mm (0.026 - 0.069 in.)
2. Service limit: 0.5 mm (0.020 in.)
Fig 1: Width Of Index Protrusion "b" (Main Shaft) Table
Courtesy of SUZUKI OF AMERICA CORP.

Fig 2: Key Slot Width "c" (High & Low Speed Synchronizer Hub) Table
Courtesy of SUZUKI OF AMERICA CORP.

Fig 3: Checking Clearance Between Synchronizer Ring & Gear
Courtesy of SUZUKI OF AMERICA CORP.
Measure width of high speed gear shift fork end "a" and groove width of high speed synchronizer sleeve "b" and then calculate clearance "c" as follows:
1. Clearance "c" = "b" - "a"
If clearance exceeds limit, replace fork and sleeve.

Clearance "c" between fork and sleeve
1. Standard: 0.15 - 0.35 mm (0.006 - 0.014 in.)
2. Limit: 1.0 mm (0.039 in.)
Fig 4: Measuring Width Of High Speed Gear Shift Fork End
Courtesy of SUZUKI OF AMERICA CORP.
Measure groove "a" of low speed gear shift fork and flange width "b" of low speed synchronizer sleeve and then calculate clearance "c" as follows:
1. Clearance "c" = "b" - "a"
If clearance exceeds limit, replace fork and sleeve.

Clearance "c" between fork and sleeve
1. Standard: 0.15 - 0.41 mm (0.006 - 0.016 in.)
2. Limit: 1.0 mm (0.039 in.)
Fig 5: Measuring Groove Of Low Speed Gear Shift Fork & Flange
Courtesy of SUZUKI OF AMERICA CORP.
- Check diameter of main shaft (1) and thickness of main shaft (1) flanges as shown in the figure. If measured value is out of specification, replace main shaft (1).
  
  Fig 6: Main Shaft Specifications (Diameter & Thickness) Table
  Courtesy of SUZUKI OF AMERICA CORP.
  
  Fig 7: Checking Diameter Of Main Shaft & Thickness Of Main Shaft Flanges
  Courtesy of SUZUKI OF AMERICA CORP.
- Using "V" blocks (1) and dial gauge (2), check runout. If runout exceeds limit below, replace main shaft (3).
  Main shaft runout
  1. Limit: 0.015 mm (0.0006 in.)
  Fig 8: Checking Main Shaft Runout
  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 (standard) of gear
  1. 1st gear: 46.015 - 46.040 mm (1.8116 - 1.8126 in.)
  2. 2nd gear: 53.015 - 53.040 mm (2.0872 - 2.0882 in.)
  3. 3rd gear: 44.015 - 44.040 mm (1.7329 - 1.7339 in.)
  Fig 9: Checking Inside Diameter Of Gear
  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
1. Standard: 0.10 - 0.25 mm (0.004 - 0.010 in.)
Fig 10: Checking 2nd Gear Thrust Clearance
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
1. Standard: 0.15 - 0.45 mm (0.006 - 0.018 in.)
Fig 11: Checking Low Gear Thrust Clearance
Courtesy of SUZUKI OF AMERICA CORP.