Mechanical Braking System

Mechanical Braking System - FADM Stern GNSF

The mechanical brake system on some models of these bikes use a mechanical lever assembly to force a set of brake shoes against a brake drum on the rear wheel.

Rear Brake Systems - Blue Fox

The rear brakes on the US CX and GL models are functionally the same. Some European models use a hydraulic piston/rotor assembly, but the US models both use an expanding shoe arrangement, actuated by a arm connected to the foot lever. We will only examine the expanding shoe type here. The rear hub contains a pair of half-circular shoes (#5) to which a friction material has been bonded to the outside. These are held slightly ajar of the wheel drum and are fastened to the drum plate (#3) on one end. The other ends are held in contact with a rod (#7) with a elongated cross section that when rotated force the shoes apart with a cam action and into contact with the drum.

Altho the rear brakes only account for a small portion of the stopping power, their operation is essential to the safety of the bike. For those who have not experienced a front wheel slide from application of the front brake on less than ideal surfaces, try using the rear brake for low speed braking in gravel lots. The rear brake acts like dragging an anchor, and won't tip you over as easily as the front. In fact, I like to use the rear for many low speed maneuvers.

There is little maintenance required on this system. The main problem area is the shaft #7 above that is inserted thru the hub. This sometimes will become difficult to turn due to rust on the shaft. Removal is straight forward and the shaft cleaned and re-lubed. Honda Moly 60 paste works well here as you also need some for the wheel splines later. I have personally encountered a bike that I was purchasing that needed a few hammer blows to the actuating arm to be able to even push the bike. A small dab of grease on the cam contacts at the shoe and some light oil in the shoe axles and they should be good.

The shoes themselves need to be checked for thickness and contamination with grease or oil. If the lining thickness is 2.0 mm or less, the shoes should be replaced. A note here in that if you purchase new shoes from Honda, you need to order 2, as they are sold singly. Other vendors may be different, so check before you purchase. Shoes contaminated with oil or grease can be partially cleaned with lacquer thinner, but the better alternative is to replace them with new.

These brakes also incorporate a wear indicator #8, that is visible outside the hub. If this indicator points to the reference mark on the hub under full application, the brakes need service. A difference between the CX models and the GL's is that the actuating rod and arm are over the top of the axle on the GL due to the Pro Link shock arrangement. The CX's rod follow below the axle to the hub.

The most common problem is that the rear brakes squeal, squeak, and make noise. This is almost always due to the friction characteristics between the shoes and the wheel drum. A glazed hard surface on the shoes against the smooth shinny drum sets up a resonant vibration not dissimilar to fingernails against a chalkboard. The remedy is to change one of the surfaces. Fingernails on cardboard are no problem. So either sand, abrade, scrape or roughen one of the surfaces. The shoes are the easiest and safest to do. Just don't overdo it and use up too much of your friction material. This may have to be repeated depending on the age and composition of your shoes.

[p225896#entry225896|Link to forum on the topic of brakes and final drive]