TECHNICAL BULLETIN FROM KNOTT-AVONRIDE
Replacement Brake Shoes
It has come to our attention that "copy" brake shoes are being offered as replacements for Knott original brake shoes. Furthermore, false statements; for example; “made in the same factory as the Knott shoe” are used to promote the sale of these parts. We therefore wish to make you aware of the potential problems and possible pitfalls associated with using these parts.
The packaging might state that these shoes are approved in accordance with R90 (Regulation 90). Primarily “Regulation 90” is a lining, packaging and marking requirement. However the fit, form and function of the brake shoe (other than brake lining performance) are elements that are not specifically covered under this Regulation. The brake shoes in question might be fitted with “approved” linings, however, the R90 approval only requires that the lining performance is within 12% of the original brake lining performance. Some versions of these “approved” linings were last used by original equipment manufacturers more than 15-20 years ago. However, they were replaced at the time due to “in service” problems. This might lead to accelerated brake shoe and brake drum wear.
This “copy” brake shoe assembly is manufactured using processes which do not ensure the correct geometry of the shoe. It can be most apparent during the automatic reversing function when the geometry of the mechanism is extremely important. This will, in turn, affect the durability of the brake shoe and the associated components. The resultant wear on the components (including the drum) will more than negate any savings that might be made on the purchase of these shoes. We have also seen examples of failure of key components which have caused brake failure.
Any future liability for the brake might be rendered void if these shoes are fitted, thereby potentially leaving those companies and individuals, responsible for supplying and fitting the shoes, personally liable for any and all subsequent claims.
Brakes are a safety critical item, we are aware of failure of “copy” components which would prevent the safe operation of the brake. For safety, always fit Knott original components.
All Knott aftersales brake shoe assemblies are:
- Precisely machined to ensure compatibility with components and drum.
- Produced to the correct chemical composition.
- Manufactured to the highest standard.
- Tested and approved to specific performance requirements.
- Type approved to give confidence and security in use.
- Dimensionally correct in accordance with approval requirements.
- Produced with inhibitors to prevent corrosion.
