Scooter and moped brake disc
In the 1970s, the first disc brake systems appeared in the scooter sector. Since then, the disc brake has established itself and is now widely used. Compared to the previously developed drum brake (with brake shoes, usually without hydraulic support), the disc brake shows better braking behaviour and works much more effectively. The brake disc
is the wheel-mounted part of a disc brake. The brake disc is always mounted on the wheel symmetrically to the centre point. It is usually available with a circular or wave-shaped outer contour. Often it is made of one piece, but sometimes it also consists of two separate surfaces. On the inside, the brake disc is provided with model-specific holes for axle mounting.
When braking, the external braking surface is gripped by the brake pads
, which in turn are worn by brake caliper
Material and production
Brake discs are often cast from grey cast iron, spheroidal graphite iron or steel alloys and then milled or machined. Holes and slots in the brake surface of the brake disc serve for ventilation and are intended to prevent overheating. Corrosion-resistant stainless steel is becoming increasingly popular for standard brake discs, as the surfaces of grey cast iron brake discs rust from moisture, which is regarded as disadvantageous and, above all, unattractive. Carbon and carbon ceramics are also used in racing. Although these materials cost the brake disc a lot more, they show a significantly better braking performance, are almost fading insensitive (the braking effect decreases when the brakes are heated) and wear out considerably less.
Checking the brake disc
Probably the most safety relevant element on the scooter is the brake system. If not everything is in uncompromisingly good condition, it can quickly become dangerous. The proper functioning of the brakes must therefore be checked regularly. If there is a defect or if a part is worn out, it must be replaced IMMEDIATELY. If the brakes rub or the brake performance is poor, the entire brake system (brake disc, brake calliper, brake lining, Brake lever
and Brake fluid
). In the case of the brake disc, the following should be observed:
- The surface of the brake disc should be flat and smooth. If the brake surface shows strong scoring (visual inspection, fingernail inspection), it must be replaced. Unlike a car brake disc, the scooter brake disc cannot be twisted off. This is because the disc quickly becomes too thin and can warp during machining.
- The thickness of the brake disc should also be checked. Depending on the brake disc, a different minimum thickness is used as the wear limit, which is usually printed on the disc. If in doubt, consult the vehicle manual or vehicle dealer.
- If the brake disc shows an unusual discolouration, it has a bluish tinge, which indicates that it has become too hot. The result is changes in the degree of hardness of the disc. In the worst case, this can lead to the brake disc breaking. Furthermore, the brake disc has probably warped and the full braking performance is no longer given. A discoloured brake disc should also be replaced! (Especially if the brake discs are overheated, it is absolutely necessary to change the brake fluid.)
In the event of abnormalities on the brake disc, brake linings and brake callipers must also be thoroughly inspected. If the brake pistons in the calliper do not run smoothly (a repair kit can help if cleaning has failed) or if the wrong brake linings are used, the brake disc will soon have to be replaced again unintentionally. Before you do this, you should check whether everything is in order. When fitting a new brake disc, new brake pads must also be used, as the old ones have adapted to the defective brake disc.
NG Brake Disc with KBA number
Many a brake disc is very attractive in its design, including the visually appealing ventilation slots and the sophisticated outer contour, and may not be installed if it does not carry a KBA (KraftFahrtBundesamt) number. The KBA number refers to the existence of an ABE that belongs to the attachment on which the KBA was printed. An entry is not required, nor is it necessary to carry an ABE as a document, as the KBA sufficiently confirms the general operating permit. In the Spanish manufacturer NG Brake Disc
we have found a brake disc specialist who has been producing brake discs for over 30 scooter, moped, quad and ATV brands for over 20 years. The top quality of the brake discs has already convinced many vehicle manufacturers who equip their models with brake discs from NG Brake Disc ex works. In addition, all NG brake discs are TÜV Rheinland certified and can be driven on public roads with their KBA number.