Information
|
Method of Inspection
|
Reason for rejection
|
A.
Roller Brake Test
|
Serious under inflation of tyres is not
a reason for failure however a tester may decide not to conduct
a brake test if tyre damage is likely.
When using a roller brake tester the wheel
not on the rollers must be braked and chocked against the reaction
force. This is especially important for lightweight machines and
those with small wheels.
In the case of a linked brake system, it may
not be possible to apply the brake of the wheel not being tested
prior to starting the test.
If a roller brake test is repeated, the chock
should be removed, the machine resettled in the rollers and the
chock replaced.
The retardation force of a side car brake
is not to be included unless it is operated by one of the motorcycle
brake controls.
The efficiency of each system operated by
a single brake control is the ratio of the total retarding force
generated by that system divided by the weight of the machine and
rider
Total retarding force for one system/weight of machine plus rider
(tester) x 100
Most machines have two controls, one operating
the front wheel brake and the other the rear wheel brake. The efficiency
for front and rear wheels can then be calculated as above (or checked
by a gradient test).
Where a linked or dual system is operated
by one control, the retarding force used in the efficiency calculation
is the total from both wheels when operated by that control only.
In this case, the other control will probably operate on one wheel.
The reasons for failure 1 and 2 apply whether single or dual systems
are fitted.
Motorcycles first registered on or after 1 January 1927 require
two means of operating the brakes, one achieving a minimum efficiency
of 30% and the other a minimum of 25%
Machines before this date are only required to have one means
of operating the brakes, which shall have an efficiency of at least
30%.
The tester may know that a higher brake efficiency
Is normally obtainable for the model tested, although the machine
has passed the performance test. In this case the owner should be
advised that the braking system appears to require adjustment or
repair,
Where there is doubt about the effect
of a defect noted during the brake test, the tester may at his discretion,
carry out a road test. (See Introduction item 10).
The assessment of bind, grab and judder
in sub-sections 3.3C and 3.3D can be
performed at any appropriate point during the test.
If a motor bicycle wheel locks on the operation of a brake control,
the efficiency requirement of 30% is considered to have been met
for that control. This does not apply to a braked wheel on a sidecar.
|
A. ROLLER BRAKE TEST
With the tester seated on the machine locate the front wheel in
the rollers of the brake tester, ensure that the machine is lined
up in the straight ahead position and settled in the rollers, (see
information column)
Select the correct direction of operation so that the wheels rotate
in the forward direction.
1. Start the brake rollers and allow the front wheel to stabilise.
With the rear brake fully applied (see information column) gradually
apply the front brake until maximum effort is achieved or the wheel
locks and slips on the rollers. Note the reading at which the maximum
braking effort is achieved and release the brake.
Start the rollers, gradually increase the front brake effort to
about half the maximum reading and observe the way it builds up.
Hold steady and check for fluctuations. Release the brake and observe
the way in which the braking effort reduces.
Move the machine forward until the rear wheel is located in the
rollers. Repeat procedures 3.3A1 and 3.3A2.
Check the side car wheel brake if applicable (see information column)
as in procedures 3.3A1 and 3.3A2.
2. Record the appropriate results of the brake test via the VTS
Device, which will calculate the results. Where the VTS device is
unserviceable see the introduction section paragraph 3.
|
1.
a sticking or binding brake, (see information column)
b. severe grab or judder, (see information column)
c. a braking effort that does not rise or fal( in proportion to
the lever or pedal force applied
d. excessive fluctuation of brake effort with steady application
of the brake. (see information column).
2.
a. no brake control achieves an efficiency of 30%
b. the less effective brake control does not achieve an efficiency
of 25% (Note: this RFR is only applied if 1 control achieves 30%
and the other control fails to achieve 25%)
c. Neither brake control achieves an efficiency of 25%
|
B. Plate Brake Test
|
As 3.3A
|
To calculate the brake efficiency it is necessary to determine
the combined weight of the motorcycle and the tester while seated
in the normal riding position.
1. At a steady speed of approximately 4 mph drive the machine onto
the plate tester. As soon as the front wheel is on the plate high
friction braking surface gradually apply the front brake until maximum
effort is achieved or the wheel locks and skids.
Note the way in which the brake effort increases and the maximum
value achieved.
Repeat procedure 1. above for the motorcycle rear wheel and in appropriate
cases (see information column) the side car wheel.
calculate the efficiency of each braking system (see information
column)
Repeat procedures 1. and 2. above a second time to confirm any
reasons for
failure.
2. Record the appropriate results of the brake test via the VTS
Device, which will calculate the results. Where the VTS device is
unserviceable see the introduction section paragraph 3.
|
1.
a. a sticking or binding brake (see information column).
b. severe grab or judder (see information
column).
c. a braking effort that does not rise or fall in proportion to
the lever or pedal force applied.
d. excessive fluctuation of brake effort with steady application
of the brake. (see information column)
2.
a. no brake control achieves an efficiency of 30%
b. the less effective brake control does not achieve an efficiency
of 25% (Note: this RFR is only applied if 1 control achieves 30%
and the other control fails to achieve 25%)
c. Neither brake control achieves an efficiency of 25%
|
C. The Floor Test
|
AS 3.3A
|
The apparatus required for this test comprises a spring balance
and system of pulleys so arranged that the effort required to pull
a machine and rider forward against the brakes may be measured.
The spring balance may be used to determine the weight of the motorcycle
and rider.
With the machine held upright and in a straight ahead position,
attach the cable from the spring balance to the front of the motorcycle
using a strap around the front forks or the headstock.
The tester should sit astride the machine operating each brake in
turn and note the readings while the assistant operates the spring
balance system.
1. With each brake applied in turn record the effort required to
move the motorcycle and rider forward.
Record the appropriate results of the brake test via the VTS
Device, which will calculate the results. Where the VTS device is
unserviceable see the introduction section paragraph 3.
|
1.
a. no brake control achieves an efficiency of 30%
b. the less effective brake control does not achieve an efficiency
of 25% (Note: this RFR is only applied if 1 control achieves 30%
and the other control fails to achieve 25%)c.
c. Neither brake control achieves an efficiency of 25%
d. a sticking or binding brake (see information column).
e. severe grab or judder (see information column).
|
D. The Gradient Test
|
As 3.3A and
To check the efficiency of 25% one end of the platform must be raised
to a height equivalent to 25% of the platform length (ie 700mm for
a 2.8m platform). Similarly to check a 30% efficiency one end must
be raised to a height equivalent to 30% of the platform length fie
840mm for a 2.8m platform). Each brake must be tested separately
and the tester must not exert any other retarding force.
|
The equipment required for this test consists of a platform one
end of which can be raised.
Raise the end of the platform by the appropriate amount, (see information
column )
1. Sit astride the 'downhill' facing machine. Apply each brake in
turn and confirm that the machine can be held stationary.
Record the appropriate results of the brake test via the VTS
Device, which will calculate the results. Where the VTS device is
unserviceable see the introduction section paragraph 3.
|
1.
a. no brake control achieves an efficiency of 30%
b. the less effective brake control does not achieve an efficiency
of 25% (Note: this RFR is only applied if 1 control achieves 30%
and the other control fails to achieve 25%)c.
c. Neither brake control achieves an efficiency of 25%
d. a sticking or binding brake (see information column).
e. severe grab or judder (see information column).
|
E. Decelerometer Test
|
As 3.3A and conducting decelerometer tests.
On a small number of machines it is not possible to carry out a
roller brake test. In these circumstances a decelerometer test may
be carried out.
It is Important that the tester has confirmed that the machine
is in a safe condition to carry out a decelerometer test. If it
is not considered safe the tester should refuse to complete the
test (introduction item 2.i)
During the decelerometer test, each application of the brake should
be gradual and the tester should endeavour to achieve only the required
percentage to pass, rather than the best possible result
Roads used for decelerometer brake testing
decelerometer testing is pottentially hazardous and it is therefore
important that the road used
. is reasonably flat and level
. has a good surface
. is suitable for brake tests with regard to the weather conditions,
and
. has a minimum of traffic
The road used for tests should be varied wherever possible to avoid
cause for complaint from residents
|
1. If the vehicle is of a type which cannot be tested on a Roller
Brake Tester
. set up the decelerometer on the machine in accordance with the
equipment manufacturer's instructions
. drive the vehicle on a level road at a steady speed of approximately
20mph (32kph) and note the brake efficiency recorded when applying
only one brake control.
. repeat the test applying only the other brake control.
. while the machine is decelerating under the action of each brake,
note the progresion of application and any grab or judder.
. record the appropriate results of the brake tests via the VTS
Device. Where the VTS Device is unserviceable see the introduction
section paragraph 3
|
1.
a. no brake control achieves an efficiency of 30%
b. the less effective brake control does not achieve an efficiency
of 25% (Note: this RFR is only applied if 1 control achieves 30%
and the other control fails to achieve 25%)c.
c. Neither brake control achieves an efficiency of 25%
d. a sticking or binding brake (see information column).
e. severe grab or judder (see information column).
|
Issue Date: September 2007
|