Hunt Bike Wheel with gravel tyre


What are the recommended tyre pressures for best performance on road tyres?


It is now widely accepted that over-inflation of your bicycle tyre actually reduces your speed, as it requires the tyre (and whole bike plus rider) to rise and effectively climb over every small bump on the road. Whilst this skittish motion feels fast, it is actually wasting your energy, whereas a tyre at a lower pressure would deform over the bumps and have a damping effect. This deformation over the bumps uses a small amount of energy in the transformation of tyre carcass' shape, but this is significantly less than the energy required to lift the rider over the many small bumps on the road or other rough surface. Going as low as you can reasonably go without causing yourself lots of pinch flats or excessive tyre deformation when cornering, is actually the best option. With these kinds of pressures you also have higher levels of grip, so you can push harder on the descents and corners. Additionally, you'll suffer less fatigue (from vibrational losses) and so keep riding faster for longer.


Maximum tyre pressures for our wheels are listed on the relevant product pages. The maximum pressure is mainly determined by the width of the tyre, with wider tyres requiring a lower maximum pressure. Maximum pressures must be observed from a safety perspective. As an example, our road specific wheelsets with a hooked rim profile have a maximum pressure of 100psi when using a 25mm tyre. However, when it comes to performance, best performance is achieved below 100psi for all riders. To obtain maximum performance from your wheel and tyre set-up, recommended pressures are generally much lower than maximum. Please see below the approximate recommended tyre pressures for road riding.


 

Road Tyre Size - Front Pressure / Rear Pressure (PSI) 


60kg Rider:

25mm - 71/76 

28mm - 62/65 


70kg Rider: 

25mm - 75/80 

28mm - 65/69 


80kg Rider: 

25mm - 80/85 

28mm - 68/73 


90kg Rider:

25mm - 84/89 

28mm - 72/77 


 


Gravel Tyre Size - Front Pressure / Rear Pressure (PSI) 


60kg Rider: 

700c x 40mm - 33/36 


70kg Rider: 

700c x 40mm - 35/38 


80kg Rider: 

700c x 40mm - 37/39 


90kg Rider:

700c x 40mm - 40/42 


 


MTB (Trail) Tyre Size - Front Pressure / Rear Pressure (PSI) 


 60kg Rider:

 700c (29”) x 58 (2.3”) - 23/25 


 70kg Rider:

 700c (29”) x 58 (2.3”) - 24/26 


 80kg Rider:

 700c (29”) x 58 (2.3”) - 25/27 


 90kg Rider:

 700c (29”) x 58 (2.3”) - 26/29 


The above is a guide, and the tyre manufacturers pressure recommendations must be observed. Never exceed the maximum pressure of the rim or tyre (whichever is lowest) and make sure that any minimum pressure requirements that tyre manufacturer states are also met. Failure to do so will not only compromise your performance on the bike but could cause a catastrophic failure which may lead to serious injury or death.  


 You should bear in mind other variables and tweak the pressures to suit you, your riding style, terrain, specific tyres, and bike: 


  • Rougher surfaces may require a slight reduction in pressure on the road to increase comfort, but off-road the pressure may need to be increased to protect the rim and tyre from impacts. 
  • Adding load to you or your bike may require some slight extra pressure in the tyres (use the rider weight as a guide). Never exceed the weight limit of your wheelset (see relevant product page for weight limits).
  • Some tyres, such as those with added protection from punctures with heavy duty sidewalls, can be stiff and require slightly lower pressures. 
  • Remember that hookless rims have an absolute maximum pressure of 5bar/72.5psi, but a tyres max pressure may be lower than this. The lowest pressure of the two should never be exceeded. 
  • Observe all pressure recommendations given by the tyre manufacturer and never exceed the maximum pressure of the tyre or the rim, whichever is lowest. 
  • Ensure that an accurate pressure gauge is used when checking your tyre’s pressure, be aware that the gauges on some pumps can be inaccurate by a high percentage. 
  • When choosing a tyre model and size make sure it is compatible with your rim. This includes, but isn’t exclusive to - tubeless compatibility, hookless compatibility and rim width. 


 


H-LOCK WEDGE (HLW) SIDEWALL WHEELS 


Only applicable to the following wheelsets purchase before Dec 2017:

  • 30 Carbon Aero Disc
  • 50 Carbon Aero Disc
  • 30 Carbon Gravel Disc


These wheels feature our HUNT H-Lock Wedge (HLW) sidewalls which are similar in design to those found on Enve SES AR4.5 Disc road wheels and Stans Avion Disc road wheels. The HUNT H-Lock Wedge sidewalls have stronger impact resistance and lock the bead in place whilst allowing the tyre to reach a wider overall size reducing rolling resistance and providing more grip.


HUNT HLW wheels are designed for wide versatility and are compatible with a large range of tyres from 25mm to 50mm, please use tyres specifically designated as TUBELESS or TUBELESS READY constructed with CARBON BEADS. These tyres have predictable bead diameters and a strong bead construction. You can use an inner tubes with these HUNT HLW rims as long as they are used in tubeless tyres. Tyres constructed with Aramid/Kevlar beads are not suitable for use with HLW rims.


Suitable tubeless road, gravel and CX tyres are available from a huge range of companies including Schwalbe, Hutchinson, Panaracer, Bontrager, Specialized, Maxxis, IRC and many more. The Schwalbe Pro One 25mm tyre weighs just 255g, is tubeless ready and is Schwalbe's class leading clincher racing tyre.


Maximum tyre pressure for HUNT HLW rims is 100 psi when used with 25-28mm tyres. 100 psi is more than enough for any rider on road. Click here to listen to a podcast exploring the science of why lower pressures were found to be faster by pro teams.


Maximum tyre pressures for other tyre sizes 30mm do not exceed 70psi, 33mm do not exceed 50psi, 35-45mm do not exceed 40psi, 46mm+ do not exceed 35psi.

Please do not exceed the maximum pressure stated on your tyre.


 


Precautions for rim braking on long descents, especially in hot weather


Key information regarding tyre and rim heat build-up during long periods of rim braking:


  • As rim braking is undertaken your kinetic energy is dissipated through heat between the brake pads and rims. This heat is then transferred to the air and tyre which are in contact with the rim.
  • The longer and heavier the braking the more heat is dissipated into the tyre.
  • Warm days obviously accentuate this problem as all components are warmer to begin with and they are less able to conduct the heat away as the differential in temperatures is much lower between air and tyre/rim. Hot road surfaces will also add to the problem.
  • As heat builds in the tyre, the air temperature in the inner tube/tyre rises and hotter air expands, this increases air pressure. If this continues it can reach levels that that tyre/inner tube are no longer able to cope with and thus they fail. A tubeless tyre can suffer the very same issues.


This is an issue that rim braked bicycle wheels of all kinds are susceptible to, and thus there are some reasonable precautions you should follow:

  • Recommend max 110psi as it has been widely accepted now that slightly lower pressures actually reduce rolling resistance. With tubeless tyres we recommend that you do not exceed 100psi, and we regularly ride our 23-25mm road tyres at 80-90psi as the rolling resistance of tubeless road tyres is very low.
  • Long descents and heavy braking carry inherent risks due to heat build-up on the braking surface, especially in hot weather. It is advisable, on all clincher or tubeless tyre systems, to drop your tyre pressure by 10psi from your normal setting. Please ensure you remain within the recommended pressure by the tyre manufacturer. This will improve grip and resistance to high- tyre pressures due to heat build-up from braking.
  • Stop regularly during long & steep descents to allow your brakes to cool. If you suspect your rims are reaching high temperatures during braking it is essential to stop riding for a period and allow them to cool before you continue. This is a reasonable and sensible action that all wheel, tyre and bike manufacturers would suggest.    .