The VFR400R NC24 (and NC21) uses a style of calipers that were popular on many bikes of the time, known as the two piston sliding caliper, manufactured by the well known Nissin Corporation. Due to several key points that we’ll discuss below this design was used on many bikes will into the 1990’s like on the CBR600F and even still today on many lower-end bikes this type of caliper is still used.
Modern day performance bikes and even the later VFR400R NC30 all use what is known as a fixed caliper, opposed piston design.
The caliper is composed of two parts...
As the brake is applied the pistons force the brake pad in the fixed part against the disc... this movement causes the adapter part to be pulled against the other side of the disc applying the brake pad on that side also.
Despite the negatives listed, if these calipers are kept in good working order and decent pads are used they work well with the bike. Problems arise mainly from a combination of neglect and age. These bikes are 20+ years old now and parts do wear out and need replacing. After reading this entire guide you should be familiar with how the calipers work, how to overhaul them and apply any of the knowledge, where needed to your own braking system.
This biggest killer of sliding caliper braking systems is neglect & poor maintenance.
The sliding "pins" that allow the caliper to move have very often seized solid on many bike I’ve seen for sale. This dramatically limits the performance of the caliper.
The two sliding pins have a very tight fitting rubber ‘boot’ seal which keeps grease in and dirt out. Many factors cause this seal to fail and allow dirt / grime into the caliper and stop the slide from working.
These are usually:
If the bike still has its original Honda rubber lines on these should be changed. Honda recommends 6 years on all of their rubber lines as a service interval. While your lines may not have failed yet there is an increased likelihood of them leaking, bulging or failing all together. Having no brakes at all wouldn’t be very safe, and a new set of braided lines come in all shapes, sizes and designs and don’t cost too much money.
Fitting the new lines a 2-line ‘race’ setup will improve lever feel.
The master cylinder has rubber seals inside it, just like the brake calipers do, it isn’t uncommon for this to be worn, if you have overhauled the calipers and fitted new lines and fluid and are still suffering poor braking performance a ‘rebuild kit’ is available for the master cylinder.
Budget pads are cheap for a reason. While a £9.00 set of Kyoto brand pads may be ok for slow city commuting do you want to put what could ultimately be your life in the hands of some cheap brake pads for the sake of £20-30?
My personal favourite brake pad for these bikes is the original Honda pad, they can be had for around £8.00 each, £15.50 at a main-dealer and 4 are required. (45105MN4008)
Worst-case that’s about £75.00 for a set of genuine pads Inc vat and delivered. Many people won’t want to pay that much, so if going for budget I suggest to spend at least £20.00 on a set. £40.00 total price.
From a personal perspective, the genuine Honda pads have the best ‘feel’ and performance in both wet and dry conditions of any pad I’ve tried, the longevity of these pads is also very high. If it is decided to keep the bike for any length of time or do serious riding I really stress the importance of these pads.
There is no point at all only overhauling part of a brake caliper if you need to do work on the braking system.
It is false economy.
The time, money and parts needed to take the calipers off the bike, remove the fluid and change components can be saved by combining all the tasks into one job. Not only will you save time but you’ll have a full new set of calipers that won’t need to be messed with until 6 months later when some maintenance ‘inspection’ is carried out.
After all, you wouldn’t buy a new car only to fill the engine up with used oil would you?
| Part Description | Quantity | Price ea. | Total Price. |
| Piston Seals | 4 | £2.95 | £11.80 |
| Piston Dust Seals | 4 | £2.00 | £8.00 |
| Boot (B) | 2 | £2.75 | £5.50 |
| Boot Pin(A) | 2 | £1.70 | £3.40 |
| Red Rubber Grease | 1 | £3.50 | |
| Slider Pin Grease | 1 | £3.50 | |
| Copper Grease | 1 | £3.50 | |
| Brake Fluid | 1 | £9.99 | |
| Total Inc VAT + Delivery | £60.00 |
I have not included brake lines or brake pads as the cost varies too much and will depend on personal preferences and budgets.
The total procedure should take between 2 – 4 hours.
Now that the calipers are ready, refit them to the bike, install the new brake lines and refill / bleed the system with new fluid. New pads will need to ‘bed’ in over the next 50 – 100 miles so apply the brakes progressively but not too often until they have finally bedded in.
Last Updated: 10th April 2010 @ 14:55:18
