Bontrager 231793 Rear hubs- Loose ball, double sealed Formula FCM, With your fingers or

Fig. 4E

Rear hubs- Loose ball, double sealed (Formula FCM)

'99, 2000, 2001 Bontrager Race and Race Disk rear wheels

Recommended tools

(2) 15mm cone wrench 12mm allen wrench Adjustable wrench Hammer

Small slot screwdriver

	DISASSEMBLY
Fig. 1E	Hub parts and names are referenced on next page.
	Remove the axle
	1. Remove external seals
	(Fig. 2E) with your fingers or
	a screwdriver. Be careful not to
	tear or mar the rubber.
	2. On the left side (non-drive)
	of the hub place a 15mm cone
	wrench on the bearing cone (Fig.
	3E).
	3. Place a 15mm cone
	wrench on the end nut (Fig. 4E).
	Loosen the end nut.
Fig. 2E
	4. Remove the end nut, large
	washer, spacer, small washer,
	and cone from the axle (Fig. 4E).
	5. Slide the axle (Fig. 4E),
	with the other end nut, washer,
	and cone still attached, out of the
	hub.
	6. Insert a thin screwdriver
	blade under the shell shield (Fig.
	5E) and pry off the shell shields
Fig. 3E	from both sides of the hub.
		8. If inspection
Axle
		shows it neces-
		sary, remove the
End		cone, washers, and
nut		end nut from the
		right side of the
Small		axle.
washer		9. Remove the
Large		ball bearings (Fig.
		6E) from both
washer	Ball cone
		sides of the hub.
Spacer

7. If it is nec- essary to remove

the freehub body, refer to the Freehub Body section, pages Freehub 1 and Freehub 2, for removal and installa- tion instructions.

When overhauling the hub bearings, it is usually not necessary to remove the freehub body.

Clean and inspect the parts

1. Use solvent to completely remove all old grease and debris from the hub, axle, and axle parts.

2. Inspect the bearing run- ning surfaces of both the cones and the ball cups (inside the hub). Replace any worn parts.

Fig. 5E

ASSEMBLY

Lubricate bearings and threads

1.Lubricate the threads on the axle with Wrench Force™ synthetic grease, or a similar product.

2.Place a bead of grease all the way around each ball cup, sufficient to hold the balls.

Fig. 6E

Assemble the hub

1.Place nine 1/4” balls in the ball cup on one side of the hub (Fig. 6E).

2.Place the shell shield, with its sharp edges facing out (Fig. 6E), into the hub. The shell shield is a press fit, so must be tapped lightly to fully seat (Fig. 7E).

Lay a cone wrench over the shell
	Fig. 7E
shield and tap the wrench with a
hammer to protect the shield and
ensure that it is flush with the
shell.

3.Repeat steps 1-2 for the other side of the hub.

4.Tighten the end nut against the fixed cone (attached to axle) by holding the cone with

a 15mm cone wrench and turn	Seal not seated
the end nut with another 15mm
	Fig. 8E
cone wrench.

5.Insert the axle through the hub from the right hand (drive) side.

7.Thread the cone, small washer, spacer, large washer, and end nut onto the axle in that order. The serrated surface of the end nut faces out.

8.From the left side of the hub, hold the cone with a 15mm cone wrench and tighten the end nut with a 15mm cone wrench.

9.Check the bearing adjustment by turning the axle with your fingers. The axle should spin smoothly without binding or feeling gritty. There should be no lateral play of the axle in the hub. Readjust the hub as necessary, and re-lock the end nut.

10.Install the external seal. Make sure the seal prop- erly seals against both the end nut and the hub shell. There should be a smooth transition from seal to sealing surface. An improperly installed seal (Fig. 8E) will allow

rapid contamination of the bearings.

After completing assembly of the hub, check its function by spinning the axle with your fingers. It should rotate freely without irregular friction. A small amount of lateral play is acceptable if the play is eliminated when the wheel is installed with the quick release properly closed.

14 2003 Bontrager Service Manual