Recommended tyre pressures vs comfort
itboffin
Posts: 20,064
Last year I suffered a ridiculous number of punctures, in my attempt to kill the PF I tried all manor of solutions, tyres, slime, thick inner tubes etc. eventually settling for Conti's excellent hard shells running at maximum pressure, I followed suit on my various road bikes by inflating to maximum and would you know it i've had less that a handful all year (doh! that's really done it). it could be coincidence but ....
Anyway i'm riding my MTB now and possibly for a while, said MTB has conti spike claw recommended 50 PSI i'm running them at 65 ie the max.
After a couple of days riding this set up i'm a broken man, my legs are screaming, i'm not sure if its the weight of the bike set up, the increased rolling resistance, the conditions or just the end of a long year. I'm going with set up (fingers in ears laa laa laa!) time to try out some more "friendly" tyre pressures.
CTC have this chart on their web site, along with this pressure calculation.
To use this chart, add the weight of rider, cycle and luggage and estimate the loading on each wheel. Up to 70% of the weight is carried by the rear tyre of a normal bicycle, but the ratio may be nearer 50:50 for a tandem, especially when the front rider is the heavier of the pair.
Note that this chart gives the minimum pressure for smooth roads. You should never let your tyres be lower than this and usually aim to pump them harder. Remember that narrow tyres lose pressure quite rapidly and should be ‘topped up’ every few days. Most people will want to use a higher pressure to minimise rolling resistance (although that reduces comfort) and to avoid tyre or rim damage on rougher surfaces. To allow for this add a safety factor to the weight of about 25% for poor roads and gravel tracks, or up to 50% for real rough-stuff.
For example: a 65kg rider on a 15kg bicycle (80kg in total) wants to ride country lanes (add 25% to make 100kg) on 28mm tyres. That’s a rear load of 65kg, for which the chart gives 5.2 bar (75psi), with 3.7 bar (55psi) for the 35kg in front. But these are minimum pressures. Tyre markings permitting one might sensibly inflate both to 6 bar (90psi).
Anyway i'm riding my MTB now and possibly for a while, said MTB has conti spike claw recommended 50 PSI i'm running them at 65 ie the max.
After a couple of days riding this set up i'm a broken man, my legs are screaming, i'm not sure if its the weight of the bike set up, the increased rolling resistance, the conditions or just the end of a long year. I'm going with set up (fingers in ears laa laa laa!) time to try out some more "friendly" tyre pressures.
CTC have this chart on their web site, along with this pressure calculation.
To use this chart, add the weight of rider, cycle and luggage and estimate the loading on each wheel. Up to 70% of the weight is carried by the rear tyre of a normal bicycle, but the ratio may be nearer 50:50 for a tandem, especially when the front rider is the heavier of the pair.
Note that this chart gives the minimum pressure for smooth roads. You should never let your tyres be lower than this and usually aim to pump them harder. Remember that narrow tyres lose pressure quite rapidly and should be ‘topped up’ every few days. Most people will want to use a higher pressure to minimise rolling resistance (although that reduces comfort) and to avoid tyre or rim damage on rougher surfaces. To allow for this add a safety factor to the weight of about 25% for poor roads and gravel tracks, or up to 50% for real rough-stuff.
For example: a 65kg rider on a 15kg bicycle (80kg in total) wants to ride country lanes (add 25% to make 100kg) on 28mm tyres. That’s a rear load of 65kg, for which the chart gives 5.2 bar (75psi), with 3.7 bar (55psi) for the 35kg in front. But these are minimum pressures. Tyre markings permitting one might sensibly inflate both to 6 bar (90psi).
Rule #5 // Harden The Feck Up.
Rule #9 // If you are out riding in bad weather, it means you are a badass. Period.
Rule #12 // The correct number of bikes to own is n+1.
Rule #42 // A bike race shall never be preceded with a swim and/or followed by a run.
Rule #9 // If you are out riding in bad weather, it means you are a badass. Period.
Rule #12 // The correct number of bikes to own is n+1.
Rule #42 // A bike race shall never be preceded with a swim and/or followed by a run.
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yes reduce the pressure, though the tyre side wall will limit how low you can go, My Mountain Bike is fitted with downhill mud tyres so at 2inch I run at 30psi which seems about right for no pinch flats but soft enough to deform over wet roots/rocks etc even at speed.
they are a fair bit more heavy weight though, sitting some way past the 1KG point.0 -
Like 99% of all my riding I mainly stick to roads, okay crap pot holed roads but hard tarmac none the less, so low pressures fill me with fear :shock:
I've considered UST tubeless etcRule #5 // Harden The Feck Up.
Rule #9 // If you are out riding in bad weather, it means you are a badass. Period.
Rule #12 // The correct number of bikes to own is n+1.
Rule #42 // A bike race shall never be preceded with a swim and/or followed by a run.0 -
Low pressure and ride better.
I run my 20mm tyres at 95psi on the front and a smidge over 100psi on the rear. I never get pinch flats on the road, although i sometimes get them leaving my garden... but only when I've not topped off the tyres in a while and they're down to 80psi.0 -
ride_whenever wrote:Low pressure and ride better.
I run my 20mm tyres at 95psi on the front and a smidge over 100psi on the rear. I never get pinch flats on the road, although i sometimes get them leaving my garden... but only when I've not topped off the tyres in a while and they're down to 80psi.
Would you consider yourself to be a heavy rider?Rule #5 // Harden The Feck Up.
Rule #9 // If you are out riding in bad weather, it means you are a badass. Period.
Rule #12 // The correct number of bikes to own is n+1.
Rule #42 // A bike race shall never be preceded with a swim and/or followed by a run.0 -
90kg naked, carrying a laptop, couple of d-locks and tools etc....
So yeah, kinda heavy!!!!! Should have put that in the original post!0 -
ride_whenever wrote:90kg naked, carrying a laptop, couple of d-locks and tools etc....
So yeah, kinda heavy!!!!! Should have put that in the original post!
Pics or it didn't happen :shock:
Rule #5 // Harden The Feck Up.
Rule #9 // If you are out riding in bad weather, it means you are a badass. Period.
Rule #12 // The correct number of bikes to own is n+1.
Rule #42 // A bike race shall never be preceded with a swim and/or followed by a run.0 -
you wish... i'm far too hot naked (except for my sidis) for general consuption 8)0
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Gator hardshells weigh around 400g (depending on the exact size) and are at 120 psi
The spikeclaw are at 65 psi and weigh 900g
That's why you are "a broken man"
Now HTFU and enjoy the resistance training0 -
vorsprung wrote:Gator hardshells weigh around 400g (depending on the exact size) and are at 120 psi
The spikeclaw are at 65 psi and weigh 900g
That's why you are "a broken man"
Now HTFU and enjoy the resistance training
an hour on the turbo sorted that out, tomorrow on the other hand :?
Don't forget the steel mountain bike with front cheap shocks, heavy M-F'erRule #5 // Harden The Feck Up.
Rule #9 // If you are out riding in bad weather, it means you are a badass. Period.
Rule #12 // The correct number of bikes to own is n+1.
Rule #42 // A bike race shall never be preceded with a swim and/or followed by a run.0
