A replacement rear disc arrived on Friday. It was either the wrong one for the bike or incorrectly marketed.
The original Honda disc is between 6.2mm and 5.8mm thick. The service limit is 5mm. If too thin, there is a danger that when the pads wear away, the pistons will over extend. The consequence is seal failure. That will inevitably occur when hydraulic pressure is high, during heavy braking.
The disc dispatched to me is brand new and only 4mm thick. It is being returned, but it causes a little research. One site on eBay states that its new replacement disc is 5mm thick. Even as brand new, it is obviously unfit for purpose. Most sites do not specify thickness.
Now that the Deauvilles are getting older, many are fitted with obviously new, after market discs. They look shiny and in excellent condition. My front discs are new and I am yet to check them. The question is,
”Are they thick enough?”
I exhort all owners to dust off a micrometer and measure the thickness of their brake discs.
I will not identify the vendor or manufacturer, as this seems to be a general problem.
New Front 4.3-4.7mm & service limit 3.5mm
New Rear 5.5-6.2mm & service limit 5mm
Section 1-11 NT700 Honda Workshop Manual
The original Honda disc is between 6.2mm and 5.8mm thick. The service limit is 5mm. If too thin, there is a danger that when the pads wear away, the pistons will over extend. The consequence is seal failure. That will inevitably occur when hydraulic pressure is high, during heavy braking.
The disc dispatched to me is brand new and only 4mm thick. It is being returned, but it causes a little research. One site on eBay states that its new replacement disc is 5mm thick. Even as brand new, it is obviously unfit for purpose. Most sites do not specify thickness.
Now that the Deauvilles are getting older, many are fitted with obviously new, after market discs. They look shiny and in excellent condition. My front discs are new and I am yet to check them. The question is,
”Are they thick enough?”
I exhort all owners to dust off a micrometer and measure the thickness of their brake discs.
I will not identify the vendor or manufacturer, as this seems to be a general problem.
New Front 4.3-4.7mm & service limit 3.5mm
New Rear 5.5-6.2mm & service limit 5mm
Section 1-11 NT700 Honda Workshop Manual
