Bunch "O" Bikes, Bendix Automatics Part 2

Trouble Shooting The Bendix Automatic

Locating Trouble

Before removing the rear wheel from the bicycle to check for trouble, the axle cone adjustment should be checked. If the cone adjustment is too tight or too loose, it should be corrected and operation checked in the bicycle. The cone adjustment should be loose enough to give a slight amount of side play at the wheel rim. If this does not correct the trouble, remove the rear wheel from bicycle and dis-assemble the Sun Gear Cone. Examine parts for mutilation, breakage and wear. Examine balance of assembly to determine if parts are properly assembled. Check parts for mutilation, breakage and wear.

Check For Indexing

In order to determine if indexing mechanism is functioning properly, check as follows:
Screw the Clutch Assembly onto the Transmission Assembly by rotating the Sprocket while holding the Clutch Assembly. The first set of fingers on the Indexing Spring should enter the m knurled bore of the High Speed Clutch without excessive bending sideways. Rotate Sprocket in either direction to determine if indexing mechanism is functioning properly.
With each backward, and subsequent forward motion, of the Sprocket, the Indexing Spring should index one space on the Indexing Sleeve. On alternate cycles, the small lugs on the Indexing Spring will restrict the travel of the High Speed Driving Clutch toward the ball race shoulder on the Control Assembly. Every other cycle should allow the end of the High Speed Driving Clutchto contact the ball race shoulder, because the lugs on the Indexing Spring will enter the open portions on the end of the High Speed Driving Clutch.
If indexing does not take place this could be caused by:
(a) Lack of engagement of Indexing Spring fingers with Indexing Sleeve ( on the Transmission Assembly ).
(b) Lack of engagement of the other set of Indexing Spring fingers with the knurled surface on the inside of the High Speed Driving Clutch.
(c) Mutilated, broken or bent fingers on the Indexing Spring.
If any of the above exists, the Indexing Spring should be replaced.

High Speed Drive Check

If proper indexing takes place and the complaint is lack of high speed drive, the following check should be made.
Assemble the High Speed Driving Assembly with large retainer in the proper end of the Hub. Place the Clutch Pack Assembly in the Hub and rotate the Sprocket in the driving direction while preventing rotation of the Clutch Assembly by holding with the fingers. If forward Sprocket rotation does not drive the Hub, reverse the Sprocket 90* ( degrees ) to index, and repeat. If Sprocket does not now rotate the Hub in the driving direction, this would indicate that the High Speed Driving Clutch is contacting the ball race shoulder on the Driver Assembly before contacting the taper in the Hub. This could be caused by wear on the driving surface of the High Speed Driving Clutch or by excessive ball race wear between the Hub and the Driver Assembly. When the High Speed Clutch engages there should be a 1/32" to 1/16" end play of the low speed clutch at the low speed taper of the hub shell. Substitute new parts and repeat the check.

Functional Check

If the check for Indexing and the High Speed Drive Check operate as described, a functional check of brake operation made be made as follows:
Re-assemble all parts in their proper order on the Axle without using the Hub. The parts should be assembled so that approximately 1" of the Axle protrudes from each end of the assembly. Tighten Locknut at the Arm end of the assembly as well as locking the Dustcap and the Sun Gear Cone Assembly in the position with the Adjusting Cone Locknut.
Rotate Sprocket in both directions holding the Sprocket member against the bearings. Determine if the Low Speed Clutch compresses the Disc Pack and returns to its driving position. ( Without the Hub, the Control Nut will contact the end of the Transmission Assembly when in the driving position ).
The Retarder end of the High Speed Driving Clutch should travel far enough to cover the end of the Transmission Assembly when Sprocket is rotated in the braking direction.
Determine if the indexing mechanism is operating properly by using the same procedure as outlined under Check For Indexing.
If the Low Speed Clutch does not compress the Disc Pack or move into its driving position this could be caused by:
(a) Week Control Nut Retarder Spring.
(b) Thread interference--Chips or foreign matter in the threads of the driving screws.
If the High Speed Driving Clutch does not travel in either direction as described above, this could be caused by:
(a) Weak High Speed Retarder Spring.
(b) Thread interference--Chips or foreign matter in the threads of the driving screws.
It is well to remember that the drag value of the Low Speed Retarder Coupling ( between the Low Speed Clutch and the Pressure Plate ) must always be greater than the drag value of the High Speed Retarder Coupling ( between the Low Speed Clutch and the High Speed Driving Clutch ). This is important for proper functioning.
When making the variuos checks, worn, broken and mutilated parts should be replaced.