1. Tyre pressure
Most damages to tyres occur due to the tyre pressure being wrong. Also, the tyre pressure significantly influences the drive behaviour of the motorcycle. The tyre pressure is prescribed by the vehicle manufacturer and may be found in the guidebook and on a badge at the rear wheel wing or the chain protector. The tyre pressure must be adjusted with the cold tyres before the journey. The tyre pressure, which increases due to the running (due to heating), may NOT be reduced. Adjust tyre pressure once per week. For journeys with pillion passengers or heave luggage the tyre pressure must be increased by 0.2 bar on the rear wheel. Tyre pressure that is too low leads to excess heating and increased fulling of the tyre, which may lead to destruction. Tyre pressure that is too high decreases the drive behaviour, the comfort and abrasion. After checking the tyre pressure do not forget to screw back on the valve cap with the rubber seal.
2. Profile depth
The minimum profile depth according to the Road Traffic Licensing Regulation is 1.6 mm. This can easily be checked in a control of the profile wear indicator. These indicators are set in the profile furrows and are located at the positions, where are labelled with "TWI" on the sidewalls.
We recommend changing the tyres with a remaining profile depth of less than 2 mm.
3. What must be considered with new tyres?
As a rule, when mounting new tubed tyres (TT) new tubes must be inserted. As the old tubes have stretched there is a danger of creases developing and materials thinning with repeated use, so that the tubes may rip open whilst driving. When mounting new tubeless tyres (TL) it is recommended for safety reasons to use new valves. As the centrifugal forces bend the valve in extreme cases by up to 90° when breaking, accelerating or in fast motorway runs etc., short valves must be used. In dynamic states for speeds of more than 200 km/h the centrifugal forces working on the mass of the valve insert are so huge that the spring preload and interior pressure do not suffice to keep the valve closed. Short valve inserts have got a higher level of spring preload than long valves.
4. Running-in new tyres
For each journey the first kilometres must be run at moderate speed (in particular in cold and humid weather) until the tyres have reached the required usage temperature, which guarantees the best bonding. New tyres have got a smooth surface. Therefore, they must be run in using a cautious driving style for a distance of approx. 200 km. The tyre needs this time in order to fully set onto the rim and to achieve its optimum bonding due to the roughening of the profile. Motorcycle tyres only develop their full performance from a certain operating temperature, thus they should initially be warmed up.
5. Consider the tyre free space
The sufficiently large free space on the motorcycle ensures that the tyre has got enough distance to the wheel cover, fork, wing etc. in all driving areas. Due to the centrifugal forces the diameter of the tyre enlarges with increasing speeds (in particular with diagonal tyres). Therefore, you must take particular consideration of changes in the wheel position, such as e.g. due to worn chains. Comply with the markings of the chain adjustment areas.
6. Mileages
High mileages are an argument for motorcycle costs, as long life spans mean lower costs. The mileage of motorcycle tyres, particularly at the rear tyres of performance-strong motorcycles, may not be compared to the mileage of vehicle or lorry tyres. The mileage of the tyre also depends heavily on the quality of driving and the motorcycle itself.
Due to the low dead weights of the motorcycles high accelerations can be realised. The rear tyre is subject to a huge level of wheel spin.
Wheel spin means wear and tear on the tyre! A pillion passenger, who increases the weight on the rear tyre in particular, is therefore justifiably called a tyre protector. The rear tyre is pressed onto the tarmac with larger forces and thus the wheel spin is far lower. The tyre keeps longer accordingly.
7. Motorcycle rims
As a rule motorcycle tyres may only be fitted to motorcycle rims. New tyre labelling regulations provide for the symbol M/C on the sidewall. It identifies tyres, which may be fitted to motorcycle rims exclusively. The right rim width is also significant for handling and stability. The mounting on too narrow or too wide rims changes the running area shape and thus has got a negative impact on the entire quality of driving.
In the past the development of the tyre and rim technology led to different rim constructions. Theory and practice resulted in two basic rim systems. Rims for tyres with tubes and rims for tubeless tyres.
8. Motorcycle tyres on performance test blocks
Performance and break test blocks are an extreme strain on tyres. Visible and hidden damages to tyres may occur in the tests, which may possible lead to a sudden failure much later only.
9. Tyre repairs
Due to specific regulations in individual countries no general recommendation for the repairs of tyres may be offered. If a repair is allowed, we recommend only repairing small leakages in the running areas with the help of mushroom head stoppers. It is prohibited to insert an inner tube to seal a damaged tyre. As a rule, we recommend to exchange the damaged tyre for your safety. In principle, the factory, which carries out the repairs, is also liable for it and assumes the product liability for the repaired tyre.
10. Recutting
Motorcycle tyres may not be recut, as this affects the safety and the quality of driving. Recutting is generally prohibited.
11. Storage of tyres
The storeroom for tyres should be cool, dry and moderately aired. The storage temperature should always be below 25°C and should not fluctuate much. Avoid the direct contact with pipes and radiators. Ozone accelerates the ageing process of the tyres; thus never store tyres near electrical motors or other devices, which produce sparks or electrical discharges, as this may result in higher concentrations of ozone. Fuels and lubricants may pit the rubber compounds and thus may make the tyres unusable. Always wipe off oil or petrol immediately using a clean cloth.
12. Mounting of tyres
In general, only trained specialists should fit any motorcycle tyres!
For tyres with profiles with specific running directions the running direction must be observed.
13. Balancing motorcycle tyres
Elastic bodies such as tyres cannot be produced absolutely rounded and balanced. Therefore, a new tyre must always be balanced after mounting. There are two methods: static and dynamic balancing. Static balancing may be without a rotation of the tyre. The dynamic balancing, however, may only be with a rotating tyre and at the same time measures the divergence of the masses in relation to the wheel middle level. For rim widths form 2.5 inches the dynamic balancing is recommended.
Important: In order to avoid the danger of losing air during the drive the balancing weights recommended by the vehicle manufacturers must be used (e.g. spoke nipple weights, plumb wire or self-adhesive rim weights).
We advise against liquid weights and liquid weight/sealing materials.
The wheels must be adjusted after each dismounting of the rear tyre or after the adjustment of the chain. Each rotation of a tyre that is wrongly adjusted leads to more wear and tear and a lower life span of the tyre, affects the quality of steering and in bends and thus the drive stability.
14. Profile & profile furrows
The profile furrows drain the water for wet roads. The more profile furrows there are on a tyre the higher is the profile negative share. A low profile depth is a sign for advanced wear and tear.
15. Rubber compounds
Their quality has got a direct influence on the life span and the bonding features of the tyre. A soft rubber compound promotes grip and traction. A hard rubber compound has got advantages regarding wear and tear. A rubber compound reinforced with silica is particularly useful in wet conditions.
16. Tyre shape
It directly influences the dynamic quality of driving of a motorcycle. The more pointed shape of sports tyres promotes precision and quality of turning. Tour tyres, however, are more aimed at stability and practicability in handling and therefore have got more rounded shapes.
17. Running area
It creates the contact between the road and the motorcycle. Often the rubber compounds in the running area and the flank differ in order to meet the specific requirements. To some extent the deformation of the running area also contributes the comfort.
18. Carcass
It bears the weight of the motorcycle, ensures stability and influences the comfort. The carcass may deform to a certain extent. In principle, the carcasses of radial designs are smoother than the traditional diagonal designs. It thus guarantees better damping.
19. Kickback
Occurs with higher speeds. The cause for kickbacks is impacts, which are transferred from diagonal grooves and corrugations to the chassis. Motorcycle tyres, which have got good absorption capacities, reduce kickbacks.
20. Tyre load identifiers
The tyre load LI (Load Index) is a code digit, which states the maximum speed of a tyre at the speed, which is indicated in the speed symbol. For V and W observe tyre load reductions. The "PR" digit is the indicator for the tyre use. According to German and European norms there are no PR identifiers for two-wheeler tyres. The Japanese standard only still provides the PR identifier. It can be compared to the European norm as follows:
4 PR = Normal design
6 PR = Reinforced design.
The permissible dimensions and tyre loads are the same for both norms. The PR digit is at no rate to be equalled to the details of the effective numbers of plies "Ply, Plies". The two identifiers have got a completely different meaning.
Tyres in reinforced designs
For motorcycle, motorbike and moped tyres, which do not have a PR identifier, a tyre design with higher tyre loads will receive the addition "reinforced" or reinf. to ensure the distinction.
e.g. 3.00 - 16 48 P reinforced,
170/80 B 15 M/C H TL reinf.
| Tyre load identifier |
Kg |
Pound |
| 20 |
80 |
176 |
| 21 |
82,5 |
182 |
| 22 |
85 |
187 |
| 23 |
87,5 |
193 |
| 24 |
90 |
198 |
| 25 |
92,5 |
207 |
| 26 |
95 |
209 |
| 27 |
97 |
214 |
| 28 |
100 |
220 |
| 29 |
103 |
227 |
| 30 |
106 |
234 |
| 31 |
109 |
240 |
| 32 |
112 |
247 |
| 33 |
115 |
254 |
| 34 |
118 |
260 |
| 35 |
121 |
267 |
| 36 |
125 |
276 |
| 37 |
128 |
282 |
| 38 |
132 |
291 |
| 39 |
136 |
300 |
| 40 |
140 |
309 |
| 41 |
145 |
320 |
| 42 |
150 |
331 |
| 43 |
155 |
342 |
| 44 |
160 |
353 |
| 45 |
165 |
364 |
| 46 |
170 |
375 |
| 47 |
175 |
386 |
| 48 |
180 |
397 |
| 49 |
185 |
408 |
| 50 |
190 |
414 |
| 51 |
195 |
430 |
| 52 |
200 |
441 |
| 53 |
206 |
454 |
| 54 |
212 |
467 |
| 55 |
218 |
481 |
| 56 |
224 |
494 |
| 57 |
230 |
507 |
| 58 |
236 |
520 |
| 59 |
243 |
536 |
| 60 |
250 |
551 |
| 61 |
257 |
567 |
| 62 |
265 |
584 |
| 63 |
272 |
600 |
| 64 |
280 |
617 |
| 65 |
290 |
639 |
| 66 |
300 |
661 |
| 67 |
307 |
677 |
| 68 |
315 |
694 |
| 69 |
325 |
716 |
| 70 |
335 |
739 |
| 71 |
345 |
761 |
| 72 |
355 |
783 |
| 73 |
365 |
805 |
| 74 |
375 |
827 |
| 75 |
387 |
853 |
| 76 |
400 |
882 |
| 77 |
412 |
908 |
| 78 |
425 |
937 |
| 79 |
437 |
963 |
| 80 |
450 |
992 |
| 81 |
462 |
1019 |
| 82 |
475 |
1047 |
| 83 |
487 |
1074 |
| 84 |
500 |
1127 |
| 85 |
515 |
1135 |
| 86 |
530 |
1168 |
| 87 |
545 |
1202 |
21. Speed identifiers
The labelling of the speed category is with the help of the speed symbol. As a rule this is a code letter.
Speed categories (km/h) Speed symbols (code letters)
Code letters Km/h
B 50
C 60
D 65
E 70
F 80
G 90
J 100
K 110
L 120
M 130
N 140
P 150
Q 160
R 170
S 180
T 190
U 200
H 210
V/VB up to 240
(V) (VB) more than 240
W up to 270
(W) more than 270
ZR more than 240
22. NHS
Abbreviation for "Not for Highway Service". Tyres labelled as such are competition tyres only and from a production date from the 1st of January 1993 may not be used on public roads in Germany.
23. M&S for motorcycle tyres
With Enduro tyres, which are designed for off-road use. If terrain competition tyres are used for firm roads we recommend to use the maximum speed for short times only, as otherwise the unequal use of the lug must be expected, which will affect the quality of use on terrains. Here is an M&S sticker for the cockpit to bring this fact back to one's mind. Thus, M&S has got nothing to do with "Matsch & Schnee (sludge and snow)" in the sense of the labelling for car tyres.
24. Valve, valve insert, valve cap
As rubber valves are subject to an ageing process there is a rule for safety reasons: "New tyre, new valve!" It is recommended to use short valve inserts only. At high speeds the centrifugal forces working on the valve inserts are so huge that the spring preload and interior pressure of the tyre do not suffice to keep the valve closed to 100%. Due to the lower masses of short valve inserts - this valve will remain closed at higher speeds. The centrifugal force, which, for example, flings the seats outwards in a wave swinger, also works on the valve insert when driving. At high enough speeds the same happens as if you were to press your fingernail against the valve insert: air escapes. The valve cap then provides the only way to prevent the pressure loss effectively. This phenomenon mostly only occurs at high speeds. But a badly produced valve insert may open already at speeds lower than 200 km/h. Therefore, the valve cap must always remain screwed on firmly. The use of airtight valve caps of metal with a rubber seal is recommended.
25. Bead
The connection with the rim is via the bead. Steel wires (bead core) embedded in the rubber make it stable. The carcass ends are laid around the bead core (bead jacket). Thus, the desired stiffness is achieved in the bead area of the tyre. The optimum connection between rim and tyre must be guaranteed at any time because the drive and break forces are transferred via the bead onto the rim or the chassis. Furthermore, the bead also has got sealing functions against the pressure loss in tubeless tyres.
26. Labelling for motorcycle tyres according to the EC regulation ECE R 75
The European Union also influences the motorcycle tyre labelling.
A standard was decreed, which effects changes to the tyre size labelling.
But motorcyclists, the trade or test institutions do not need to rethink completely.
This is because similar labelling is already known for tyres to the speed category H. The labelling changes mainly affect V, VB, VR and ZR tyres.
The significant difference between the labelling to date and the new labelling is the introduction of the factory identifier (tyre load identifier and speed symbol) as well as the new speed symbol W (= 270 km/h) for ZR tyres. The speed symbol V (to date V = more than 210 km/h) was redefined as V = 240 km/h.
If a tyre with the speed identifier V corresponds to the speed of 240 km/h the speed identifier within the tyre size is omitted and the factory identifier (tyre load identifier and speed symbol) is listed after the tyre size labelling (e.g. 69 V).
For ZR tyres with the speed 270 km/h the tyre label remains unchanged and the factory identifier is listed with the tyre label (e.g. 69 W).
If the permissible maximum speed of a tyre for V/VB/VR is more than 240 km/h or for ZR is more than 270 km/h the labelling to date remains unchanged and the factory identifier (tyre load identifier and speed symbol) is added. Hereby, the factory identifier is set in brackets in order to emphasise that the permissible maximum speed is more than V = 240 km/h or W = 270 km/h, e.g. (69 V), (69 W).
27. M/C
The signature points out that this is a motorcycle tyre, which may exclusively be mounted on a motorcycle rim. M/C = motorcycle
28. Low section tyres
Modern motorcycle tyres are usually low section tyre constructions: The flank height is shorter than width of the running area. This leads to more rubber on the road as well as higher levels of stability. A tyre of the dimension 120/70 ZR 17, for example, is 120 mm in width and 84 mm (70 percent of 120 mm) in height.
29. Silica
Silica (silicic acid gel) as an ingredient to the rubber compound guarantees the motorcycle tyre's better bonding in wet conditions. Furthermore, this ingredient also has got a positive effect on the mileage and the rolling friction.
30. Fulling
Due to the periodic deflecting the tyres are deformed. The textile layers of the tyre substructure work (full), which releases heat. This stresses and ages the tyre.
31. TT/ TL tyres
Motorcycle tyres with tubes (TT)
Delticom in principle recommends to use new tubes, when mounting tyres, which must be run with tubes. This is because tubes are stretched in their use and due to the heat (fulling) are subject to natural ageing processes. If they are reused in new tyres this might for example lead to the development of dangerous creases. Also, the use of repaired tubes is not recommended in the long-term, in particular with tyres for higher speeds.
Motorcycle tyres without tubes (TL)
Motorcycle tyres in tubeless designs may be used on tube rims, when used with a tube.
32. Reinforced
Tyres with reinforced carcass structure and increased tyre load are recognisable due to the labelling introduced in the dimension identifier: reinf. Tyre design, which is often required for very heavy motorcycle.
33. Coloured balancing point on the sidewall
Often the tyres are balanced after production and then marked with a coloured point (red for Metzeler/Pirelli, yellow for Bridgestone and Dunlop). This section is called the balancing point. When mounting a tyre the balancing point must be positioned at the valve - the heaviest point of the rim.
34. TWI (Tread Wear Indicator)
Tread Wear Indicator. Little crosspieces in the profile furrows, which indicate the wear and tear limit. These crosspieces are optimised for the US American market and indicate the remaining profile depth of approx. 0.8-1.0 mm. For Germany the TWI is not an indicator to determine the remaining profile depth, as the minimum profile depth is around 1.6 mm.
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