| Most common failures | No# failures |
|---|
| Headlamp aim out of alignment | 284 |
| Rear Stop lamp does not illuminate immediately a brake applies |1.3.1a| | 100 |
| Drive chain excessively loose |6.2.1d| | 88 |
| Registration plate issues | 51 |
| Front position lamp does not illuminate immediately when switched on |1.1.3a| | 49 |
| Stop lamp does not illuminate immediately a brake applies |1.3.1a| | 47 |
| Rear position lamp does not illuminate immediately when it is switched on |1.1.3a| | 47 |
| Front Roller brake test indicates a binding brake |3.3.A1a| | 39 |
| Horn not working |1.7.3a| | 38 |
| Drive chain worn to excess |6.2.1e| | 38 |
| Exhaust is leaking and excessively noisey |7.1.1b| | 34 |
| Front Stop lamp does not illuminate immediately a brake applies |1.3.1a| | 33 |
| Steering movement excessively `notchy` with the wheel raised |2.2.1b| | 29 |
| Throttle operating incorrectly |6.2.1f| | 28 |
| Registration plate lamp issues | 22 |
| Front Roller brake test indicates excessive fluctuation of brake effort |3.3.A1d| | 21 |
| Drive chain excessively tight |6.2.1d| | 20 |
| Rear Drive chain sprocket worn to excess |6.2.1e| | 19 |
| Rear Roller brake test indicates a binding brake |3.3.A1a| | 18 |
| Headlamp at least one does not illuminate on dipped beam |1.2.2a|i|| | 17 |
| Offside Front Direction indicator not working |1.5.1c| | 16 |
| Rear Brake disc|s| excessively worn |3.2.A1l| | 16 |
| Steering movement excessively `notchy` with the weight on the lower bearing |2.2.1a| | 14 |
| Rear Drive chain excessively loose |6.2.1d| | 14 |
| Offside Rear Footrest missing |6.2.1a| | 14 |
| Front Position lamp not working (4.2.1 (a)) | 14 |
| Rear Rear position lamp does not illuminate immediately when it is switched on |1.1.3a| | 14 |
| Front Floor brake test indicates a binding brake |3.3.C2c| | 13 |
| Rear reflector on motorcycle missing |1.4.1| | 13 |
| Handlebar deformed |2.1.1b| | 11 |
| Offside Rear position lamp does not illuminate immediately when it is switched on |1.1.3a| | 11 |
| Exhaust mounting does not fully support the exhaust system |7.1.1.c| | 11 |
| Nearside Handlebar handgrip not secure to handlebars. |2.1.1c| | 11 |
| Nearside Front Direction indicator not working |1.5.1c| | 10 |
| Headlamp aim beam image kick up to the offside |1.6| | 10 |
| Front Brake excessively binding (1.2.1 (f)) | 9 |
| Exhaust excessively deteriorated |7.1.1a| | 9 |
| Rear Stop lamp not working (4.3.1 (a) (ii)) | 9 |
| Front Roller brake test indicates a sticking brake |3.3.A1a| | 9 |
| Direction indicators flashing more than 120 times per minute |1.5.1c| | 9 |
| Horn not loud enough to be heard by another road user |1.7.3a| | 9 |
| Headlamp at least one does not illuminate on main beam |1.2.2a|ii|| | 9 |
| Roller brake test The less effective brake control does not achieve an efficiency of 25%. |3.3.A2b| | 9 |
| Rear Stop lamp remains on when the brake is released |1.3.1e| | 8 |
| Drive chain excessively loose |6.1.7 |c| |i|| | 8 |
| Front shock absorber seal failed and leaking oil |2.3.3| | 8 |
| Exhaust noise is clearly in excess of that emitted by a similar motor bicycle fitted with a standard silencer in average condition |7.1.2| | 7 |
| Rear Wheel alignment incorrect which adversely affects the handling |2.5.1| | 7 |
| Front Brake excessively binding |1.2.1 |f|| | 7 |
| Rear Position lamp not working (4.2.1 (a)) | 7 |
| Nearside Rear position lamp does not illuminate immediately when it is switched on |1.1.3a| | 7 |
| Wheel alignment incorrect which adversely affects the handling |2.5.1| | 7 |
| Nearside Rear Direction indicator not working |1.5.1c| | 7 |
| Rear Drive chain worn to excess |6.2.1e| | 6 |
| Rear Valve stem seriously damaged (5.2.3 (j)) | 6 |
| Offside Front Direction indicator insecure |1.5.3b| | 6 |
| Front Drive chain sprocket worn to excess |6.2.1e| | 6 |
| Drive chain excessively loose (6.1.7 (c) (i)) | 6 |
| Front Front position lamp does not illuminate immediately when switched on |1.1.3a| | 6 |
| Offside Front Front shock absorber seal failed and leaking oil |2.3.3| | 6 |
| Rear Brake disc|s| excessively scored |3.2.A1l| | 6 |
| Offside Front Direction indicators not working |1.5.1c| | 6 |
| Offside Rear Footrest insecure |6.2.1a| | 6 |
| Rear Stop lamp not working |4.3.1 |a| |ii|| | 5 |
| Offside Rear Direction indicators not working |1.5.1c| | 5 |
| Rear Position lamp not working |4.2.1 |a|| | 5 |
| Locking device|s| not correctly fitted which may make the motor bicycle dangerous to ride |6.2.1h| | 5 |
| Rear position lamp adversely affected by the operation of another lamp |1.1.3b| | 5 |
| Stop lamp affected by the operation of another lamp |1.3.2| | 5 |
| Rear Brake excessively binding (1.2.1 (f)) | 5 |
| Nearside Front shock absorber seal failed and leaking oil |2.3.3| | 5 |
| Front Wheel has an excessively distorted bead rim. |4.2.2| | 5 |
| Nearside Front Direction indicators not working |1.5.1c| | 5 |
| Horn not working |7.7 |a| |ii|| | 5 |
| Offside Front Direction indicator incorrect colour |1.5.1b| | 5 |
| Nearside Rear Drive chain excessively loose |6.2.1d| | 5 |
| Rear wheel bearings have excessive free play |2.4.A.2c| | 5 |
| Front Brake lever cannot be applied smoothly |3.1.3d| | 5 |
| Nearside Stop lamp does not illuminate immediately a brake applies |1.3.1a| | 5 |