SAFETY FIRST: Protective gloves and eyewear are recommended at this point.
Crankshaft and Transmission Disassembly
Using a 2 x 4, cut two pieces 11 inches long and two pieces that are 14 inches long. Using three inch wood screws assemble an engine cradle box to support the engine while working on it.
Remove the engine from the frame and place it in the engine cradle box on a sturdy workbench. See the Engine Removal and Installation topic for more information.
Remove the starter motor. See the Starter Motor topic for more information.
Remove the cylinder head. See the Cylinder Head topic for more information.
Remove the cylinder. See the Cylinder topic for more information.
Remove the piston. See the Piston topic for more information.
Remove the water pump. See the Water Pump topic for more information.
Remove the clutch. See the Clutch topic for more information.
Remove the right side engine components. See the Right Side Engine Components topic for more information.
Remove the left side engine components. See the Left Side Engine Components topic for more information.
Crankcase Splitting
Loosen the neutral switch with a 14 mm socket. Remove the neutral switch and sealing washer. Discard the sealing washer.
Remove the snap ring from the end of the countershaft with snap ring pliers. Discard the snap ring.
Remove the spacer from the countershaft.
Remove the countershaft sleeve and O-ring. Discard the O-ring.
There are 15 crankcase bolts that should be loosened with an 8 mm socket and three that should be loosened with a 10 mm socket.
Remove the 15 bolts with an 8 mm socket.
Remove the three bolts with a 10 mm socket.
Position the crankshaft so that the rod is at the bottom of its stroke. Install a crankshaft jig between the crank weights. Set the crankcase on its right side.
Special Tool Crankshaft Jig: 57001-1174
Use a crankcase splitting tool to separate the halves of the crankcase. Fit the crankcase splitting tool onto the left side of the engine. Make sure the tool sits evenly.
Special Tools – Crankcase Splitting Tool Assembly: 57001-1362 and 57001-1098
Lift the left half of the engine case off of the right.
Remove the dowel pins.
Clean away the old gasket material from the crankcase mating surface.
To remove the oil fitting take out the two oil fitting bolts with an 8 mm socket.
Remove the oil fitting. Discard the O-ring.
Crankshaft
Remove the crankshaft from the right crankcase half. Heating the inner race of the crankshaft bearing with a heat gun will make this job easier.
Check the crankshaft runout using a dial indicator with a magnetic base and a set of V blocks. Compare your readings with specification and replace as necessary.
Crankshaft runout: no more than .10 mm or .004 inches
Balancer Shafts
Remove the balancer shafts and inspect them for damage. Replace as necessary.
Transmission
Remove the shift fork shafts.
Remove the shift forks.
Inspect the shift fork tips and the base of the U on each side. If the shift fork tips are visually worn or if there is a curved wear mark at the base of the U, the shifts fork should be replaced. Using vernier calipers, measure the thickness of the shift fork tips. If the measurement for any shift fork is not within specification you will need to replace the shift fork.
Shift fork thickness: no less than 4.3 mm or .169 inches
Remove the shift drum and inspect the shift fork grooves for wear, replace as necessary.
Remove the two transmission shaft assemblies as a unit.
Inspect all of the crankcase bearings by turning them with your fingers. Replace any bearings that feel rough or don’t turn freely.
Disassemble the transmission shafts using a pair of external snap ring pliers. Pay attention to which way the gears face on the shaft before removing them. Lay the parts on a clean work bench in the order and direction that they are removed.
The protrusions on the gears are called the dogs. Inspect all of the gear dogs carefully for wear. Also inspect the holes on adjoining gears that the dogs fit into. Damage to the dogs or dog holes can cause the transmission to jump out of gear. Replace any gears that are damaged. Always oil the inside of any gear or bushing before installation. Never re-use snap rings or circlips.
Reassemble the transmission shafts in the reverse order of disassembly, with the following notations.
New snap rings have a sharp edge and a slightly rounded edge from the stamping process. Always install the snap ring so that the sharp edge is facing away from the gear that is putting thrust against it, and make sure it is fully seated in its groove.
When installing toothed washers onto the splines of the shaft, always rotate the toothed washer in its groove so that the teeth of the washer are offset from the teeth of the splines.
Before reassembly make sure to oil and lube all shafts, bearings and seals with engine oil.
Crankshaft and Transmission Reassembly
When installing the crankshaft, use a suitable crank installation tool to fit the crankshaft into the right crankcase half. Using a heat gun to heat up the crankshaft bearing inner race will make this job easier. The photo is not of the Kawasaki KLR650 (plus it’s the left case half), but the procedures are the same.
Lay the right crankcase half in the engine cradle box. Scrape any old gasket material from the engine cases and covers.
Install the balancer shafts. The rear balancer shaft weight fits inside the engine cases. Make sure to align the punch mark on the weight with the punch mark in the end of the balancer shaft (highlighted with a dot of white paint in the photo).
Note: Failure to align the timing marks will cause the engine to vibrate excessively.
Install the transmission gears as an assembly into the right crankcase half.
Install the shift drum.
Install the shift forks and pivot pins in their correct position in the transmission. Before joining the crankcase halves, rotate the shafts to ensure the gears mesh properly. Clean the crankcase mating surface and oil passages with a high-flash point solvent and compressed air.
Install the oil fitting with a new O-ring.
Install the two oil fitting bolts and tighten them to specification with an 8 mm socket.
Engine Oil Feed Fitting Bolts: 8.8 N-m, 78 in-lb
Install the dowel pins into the right crankcase half.
Apply silicone sealant to the left crankcase half as indicated.
Sealant – liquid Gasket, TB1211F: 92104-1063
Position the crankshaft so that the rod is at the bottom of its stroke and points toward the cylinder opening. Install a crankshaft jig between the crank weights. Set the left crankcase half on the right.
Special Tool Crankshaft Jig: 57001-1174
Fit the crankcases together evenly. Make sure the transmission, balancer, and crank shafts fit correctly in both cases.
Insert the 15 small diameter crankcase bolts and the three large diameter crankcase bolts. Apply a non-permanent thread locking agent (Blue Loctite) to the threads of the 60 mm long bolt.
Qty / Length / Color in Photo
8 – 30 mm Bolts (Red)
6 – 50 mm Bolts (Green)
1 – 60 mm Bolt (Blue)
3 – 80 mm Bolts (Purple)
Tighten the crankcase bolts evenly to specification. Start with the bolts nearest the crankshaft and work out from there. tighten the large diameter bolts with a 10 mm socket and the smaller bolts with an 8 mm socket.
Bearing Retaining Screws: 4.4 N-m, 39 in-lb
Crankcase Bolts (L = 60): 8.8 N-m, 78 in-lb
Crankcase Bolts (L = 30 & 50): 8.8 N-m, 78 in-lb
Crankcase Bolts (L = 80): 16.5 N-m, 12 ft-lb
Coat the countershaft collar and new countershaft O-ring in grease. Install the O-ring and collar onto the countershaft. The oil grooves on the collar should face towards the right side.
Make sure the right side countershaft needle bearing hasn’t fallen out. Place the spacer on the end of the countershaft.
Install a new snap ring into the groove on the right end of the countershaft.
Make sure the crank and transmission shafts turn correctly.
Install the neutral switch with a new sealing washer. Tighten it to specification with 14 mm socket.
Neutral Switch: 15 N-m, 11 ft-lb