Scooter and Motorcycle Tyre Information

Looking for motorbike tyres?

Use the links below to go straight to a section

Running in new tyres

Why you should run in new tyres

How to run in sor scrub in new tyres

What the letters and numbers mean

Tyre speed ratings

Tyre load ratings

Types of tyre

Combinations of tyre types

Useful information

Motorcycle and scooter tyres, the law and MOT's

Tyre pressures

Tyre clearances


Running in a New Scooter or Motorcycle Tyre
New tyres can be very slippery (especially if ridden in the wet) and need to be 'run in' correctly to help prevent any accidents.
The slippery surface on a new tyre is caused by 2 main reasons.
~When new, a tyre has a very smooth surface and in order to obtain maximum grip, the smooth surface needs to be 'scrubbed in'.
~Some manufacturers use 'releasing agents' when they make the tyres. These 'releasing agents' contain 'anti-ageing preservatives' which help to stop a tyre degrading whilst in storage. Releasing agents need to be scrubbed from a new tyres surface.


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Other Reasons for Running in New Scooter or Motorcycle Tyre's
~A new tyre needs to be seated on the wheel. This is not fully achieved when fitting a tyre and it needs to be ridden on with caution to complete the process.
~In order to achieve optimum performance, the various components of the tyre (belts, tread strip etc) need to be correctly bedded in to one another. If not run in correctly, a tyre may not give the best possible performance.


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How to Run or Scrub In New Scooter or Motorbike Tyre's
Although rubbing a new tyres surface with an abrasive material (like emery paper) doesn't help the running in process, it can help to remove releasing agents and assist with providing initial grip.

A new tyre should be run in for at least 100 miles (or more in wet or poor conditions)
The motorbike or scooter should be kept as upright as possible for the first 50 miles, then gradually leaned into the corners. As the mileage increases, the lean angle can be increased. Try to avoid harsh acceleration and braking and keep the power delivery as smooth as possible whilst running in tyres.


Most incidents where riders come off their motorcycles or scooters after fitting new tyres usually happen at low speeds (when the forces acting on the tyre are lower) and because of the following reasons:


~Pulling out onto the road when leaving the fitting bay or just after fitting a new tyre
~Turning right when pulling out of a T junction
~On a low speed roundabout


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What the Letters and Numbers Mean (Tyre Dimensions)
The tables below are examples of some of the more commonly used tyre sizes


190/50 ZR17 M/C

Tyre sizeDescription

190


Section (width) in mm


50


Aspect (height) of the tyre. Shown as a percentage of the tyre width


Z


Speed rating (Z=150+mph)


R


Radial construction tyre


17


Wheel rim diameter in inches


M/C


Tyre constructed for motorcycle use

 

150/60 R17 M/C 66H

Tyre sizeDescription

150


Section (width) in mm


60


Aspect (height) of the tyre. Shown as a percentage of the tyre width


R


Radial construction tyre


17


Wheel rim diameter in inches


M/C


Tyre constructed for motorcycle use


66


Load index (how much weight the tyre can take)


H


Speed rating (H=up tp 130mph)

 

150/70-17 M/C 69V

Tyre sizeDescription

150


Section (width) in mm


70


Aspect (height) of the tyre. Shown as a percentage of the tyre width


-


Bias-ply (cross ply) construction tyre


17


Wheel rim diameter in inches


M/C


Tyre constructed for motorcycle use


69


Load index (how much weight the tyre can take)


V


Speed rating (V=up tp 150mph)

 

3.00-19 M/C 49S

Tyre sizeDescription

3.00


Section (width) in Inches


-


Bias-ply (cross ply) construction tyre


19


Wheel rim diameter in inches


M/C


Tyre constructed for motorcycle use


49


Load index (how much weight the tyre can take)


S


Speed rating (H=up tp 112mph)

 

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Scooter and Motorcycle Tyre Speed Ratings
The table below is of the speed ratings for different tyres (e.g. 150/70-17 M/C 69V). It is not advisable to fit lower or higher rated tyres on a motorcycle or scooter (for example-fitting 'F' or 50mph rated tyres on a Suzuki GSXR1000!). Even if you never travel at the speeds indicated by a tyres speed rating, fitting incorrectly rated tyres will result in sever loss of performance and handling and may result in tyre failure (blow out!).



Letter


Max MPH


Max KPH


B


31 mph


50 kph


F


50 mph


80 kph


J


62 mph


100 kph


L


74 mph


120 kph


M


81 mph


130 kph


N


87 mph


140 kph


P


93 mph


150 kph


Q


100 mph


160 kph


R


106 mph


170 kph


S


112 mph


180 kph


T


118 mph


190 kph


H


130 mph


210 kph


V


up to 149 mph


up to 240 kph


(V)


over 149 mph


over 240 kph


Z


over 149 mph


over 240 kph


W


up to 168 mph


up to 270 kph


(W)


over 168 mph


over 270 kph

 

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Motorbike and Scooter Load Ratings (Index)
The table below shows how many kilograms different tyre load rating numbers are suitable to take



Load Index


KG's


0


45 kg


1


46.2 kg


2


47.5 kg


3


48.7 kg


4


50 kg


5


51.5 kg


6


53 kg


7


54.5 kg


8


56 kg


9


58 kg


10


60 kg


11


61.5 kg


12


63 kg


13


65 kg


14


67 kg


15


69 kg


16


71 kg


17


73 kg


18


75 kg


19


77.5 kg


20


80 kg


21


82.5 kg


22


85 kg


23


87.5 kg


24


90 kg


25

92.5 kg

26

95 kg

27

97.5 kg

28

100 kg

29

103 kg

30

106 kg

31

109 kg

32

112 kg

33

115 kg

34

118 kg

35

121 kg

36

125 kg

37

128 kg

38

132 kg

39

136 kg

40

140 kg

41

145 kg

42

150 kg

43

155 kg

44

160 kg

45

165 kg

46

170 kg

47

175 kg

48

180 kg

49

185 kg

50

190 kg

51

195 kg

52

200 kg

53

206 kg

54

212 kg

55

218 kg

56

224 kg

57

230 kg

58

236 kg

59

243 kg

60

250 kg

61

257 kg

62

265 kg

63

272 kg

64

280 kg

65

290 kg

66

300 kg

67

307 kg

68

315 kg

69

325 kg

70

335 kg

71

345 kg

72

355 kg

73

365 kg

74

375 kg

75

387 kg

76

400 kg

77

412 kg

78

425 kg

79

437 kg

80

450 kg

81

462 kg

82

475 kg

83

487 kg

84

500 kg

85

515 kg

86

530 kg

87

545 kg

88

560 kg

89

580 kg

90

600 kg

91

615 kg

92

630 kg

93

650 kg

94

670 kg

95

690 kg

96

710 kg

97

730 kg

98

750 kg

99

775 kg

 

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Different Types of Scooter and Motorcycle Tyres
There are 3 main types of motorcycle and scooter tyre construction.


Radial tyres~These are generally wider tyres designed to fit on wider rims. Radial tyres have a more supple or flexible carcass which makes them better suited to modern motorcycles.


Bias tyres~These are generally narrower tyres designed for bikes produced in the 1980's with more rigid frames.


Crossply~Designed for classic motorbikes and scooters and generally fitted with an innertube inside the tyre.


Tyres can also be split into 2 main group's:


Tube type tyres~These tyres require an inner tube to be fitted inside the tyre. Most spoked wheel motorcycles (for example off road and MX motorcycles) use a tube type tyre because without an innertube, the air would seep out of the holes where the spokes go in.


Tubeless tyres~These tyres don't require an inner tube. Fitted commonly to most modern solid wheel bikes


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Combinations of Tyre Types That Can or Can't Be Fitted
The charts below show combinations of tyre types that can and can't be used on a motorcycle. Using the wrong tyre types will mean an MOT failure.
Please remember-Just because a mixed construction fitment is legal doesn't necessarily mean that it will be suitable for the motorbike or scooter.


The mixture's of tyre types below are legal in the UK


Front tyre


Rear tyre


Bias-ply front


Bias-ply rear


Bias-belt front


Bias-belt rear


Radial front


Radial rear


Bias-ply front


Bias-belt rear


Bias-ply front


Radial rear


Bias-belt front


Radial rear

 

The mixture's of tyre types below are illegal in the UK


Front tyre


Rear tyre


Bias-belt front


Bias-ply rear


Radial front


Bias-ply rear


Radial front


Bias-belt rear

 

Useful Information

Tyre Pressure Conversion Chart


Bar


PSI (pounds per square inch)


1.2


17


1.25


18


1.3


19


1.4


20


1.5


22


1.6


23


1.7


24


1.75


25


1.8


26


1.9


28


2.0


29


2.1


30


2.2


31


2.25


32


2.3


33


2.4


34


2.5


36


2.6


37


2.7


39


2.8


40


2.9


42


3.0


44


3.1


45


3.2


46

 

Alpha to metric conversion table


Alpha size


Equivalent metric size


MH90


80/90


MJ90


90/90


MM90


100/90


MN90


110/90


MR90


120/90


MT90


130/90


MU85


140/80


MU90


140/90


MV85


150/80


MV90


150/90


For example: A tyre marked MT90-16 is the same as a 130/90-16 tyre.
A tyre marked MH90-21 would be the same as an 80/90-21 tyre.


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Scooter and Motorcycle Tyres, MOT's and the Law
Below are the guidelines for checking your motorcycle or scooter tyres to ensure they are safe for road use and to ensure they meet MOT and legal requirements for the UK.


Tread depth and tyre condition
Over one quarter of MOT test failures are due to worn tyres and running your motorbike or scooter on badly worn tyres can result in heavy fines and points on your licence!


Below are a few legal and MOT requirements:


~Tyres must be suitable (i.e. of the correct specification and size) for the use to which the vehicle is being put and must be inflated to the vehicle or tyre manufacturers' recommended pressures (in other words, don't try and put car tyres on a motorbike!).


~If fitted with a direction arrow, tyres must be fitted to spin in the direction of forward wheel rotation


~Tyres will be checked for tread depth and condition as well as sidewall condition (look for age cracks starting to appear on the tyre's wall)


~Bikes and scooters up to 49cc (max speed 30mph) must have visible tread on the tyre


~Bikes and scooters over 49cc (or that can travel above 30mph) must have at least 1mm of visible tread over 75% of the tyre and the tread must be continuous (so you can't have 40% of the tyre on each side with good tread and a bald stripe in the middle!)


Most manufacturers recommend changing tyres once the tread depth is down to 2mm as once the tread gets below 2mm, acceleration, braking and handling can be severely affected.


~A cut in excess of 25mm or 10% of the section (width of the tyre) , whichever is the greater, measured in any direction on the outside of the tyre and deep enough to reach the ply or cord would deem the tyre illegal.


~The tyre must not have any lump, bulge or tear caused by separation or partial failure of its structure


Scooter and Motorcycle Tyre 'E' Marks


From 1 June 1997 all new motorbike and scooter tyres must be ECE or EU approved and display an 'E' or 'e' mark.


Since 1 January 1995 it has been illegal for any person to supply re-treaded tyres unless they are marked to indicate compliance with the current BS AU 144 standard. It is also illegal for any person to supply a part-worn tyre which does not comply with legal requirements and which does not have tread grooves at least 2mm deep.


Motorcycle, Scooter and Puncture repairs


Legal number of repairs allowed for MOT's:


Up to 'J' speed rating-a maximum of 2 repairs, not exceeding 6mm in diameter.
'L' to 'V' speed ratings-a maximum of 1 repair not exceeding 3mm in diameter
No repairs are permitted on tyres above the 'V' speed rating (as stated by the BSAU159f)

The repairs are restricted to the center of the tread area, not more than 25% of the tyres width either side of the center line and not on the tyres sidewall.
Repairs must be made using a 'mushroom' type plug.


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Scooter and Motorcycle Tyre Pressures
Motorcycle and scooter tyres slowly lose air pressure through the rubber of the tyre, which is why it is important to regularly check the tyre pressures before riding.

Check tyre pressures once a week and always when the tyres are cold. Correct inflation pressures are critical to a motorcycle or scooter's safe handling.
Incorrect inflation pressures can lead to tyre damage, poor handling and irregular and rapid wear.
If tyre pressures have been adjusted for 'off road use' (e.g. track days or trial riding) they must be returned back to the recommended pressures before being used back on the road.

Check your owners manuel for the manufacturers recommended tyre pressures. On many bikes, recommended tyre pressures can also be found on the chain guard.

Tyre pressure is the first thing you should check if the bike starts handling badly. Even a couple of pounds difference in the pressure can make a huge difference and rapidly increase a tyres wear.


The effect of over or under inflation can is shown in the pictures below:
Under inflated   Correctly inflated   Over inflated


As a very rough guideline............


Most scooters run tyres around 30psi in the front and rear tyres (often around 26psi in the front and 29psi in the rear)


Most sports/touring/commuting motorbikes run 36psi in the front tyre and 42psi in the rear


But, the above pressures are very rough guidelines only, you should check your bike's handbook or ask the manufacturer or authorised dealer for the exact tyre pressures!


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Motorbike and Scooter Tyre Clearance
As a tyre rotates, the movement forces and the heat generated cause the tyre to expand (this effect is greater in Bias-ply or Crossply tyres).
As a general guideline, always make sure there is at least 4mm of lateral (sideways) clearance and 14mm of radial clearance between the tyre and any part of the motorcycle or scooter, especially the mudguards, forks, swing-arm and hugger.
Be especially careful when fitting tyre sizes other than the manufacturers recommended tyre sizes.


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Rear Bike Tyre