Am I overinflating my tyres?
- Thread starter hoppym27
- Start date
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MacB
Lover of things that come in 3's
- Location
- Farnborough, Hampshire
Depends on your weight for what's best but also on how plush you want your ride to feel. At 17 stone I ran 700x35 M+ tyres at 50 front and rear for thousands of miles without incident. By any standard theory that was way too low, I just didn't know any different at the time. But even on 700x23 and at 16 stone I never went higher than 90 on the rear, again too low by all acounts and again no problem.
OP
OP
hoppym27
Well-Known Member
I can't spot on there where it tells me the pressures
vickster
Legendary Member
Columns 6 & 7 in the table unless I'm missing something? 50 (rec) & 87 (max) for the 42mm variant
presta
Legendary Member
Schwalbe publish a technical info file here:
SCHWALBE TECH INFO BICYCLE TIRES - Edition 3, 2015
SCHWALBE TECH INFO BICYCLE TIRES - Edition 3, 2015
Ajax Bay
Guru
- Location
- East Devon
These pressures are far too much, unless your bike and luggage plus you weigh 170kg+.
See the attachment (graph only goes to 37mm width but easy to extrapolate). I'm assuming your 700x42c tyres actually measure 42mm wide.
If your total all up weight is 100kg, this will be split 60kg rear and 40kg front (hybrid) and my reading of the graph suggests pressures of 45psi rear and 38psi front.
MacB
Lover of things that come in 3's
- Location
- Farnborough, Hampshire
Hoppy, you need to be aware that there is no exact answer here as your own subjective comfort levels will be....your own. I suppose there is an absolute range with the low end being too soft to prevent pinch punctures and the high end exploding the tyre off the rim. I'd guess that probably gives you a range of about 20-140PSI but, for experimenting purposes, I'd use a range of 40-65psi.
Theoretically the lower pressure will give more comfort but less speed and vice versa - personally I've never noticed much in the way of speed variance but I do feel the lack of comfort if a tyre is too firm.
Theoretically the lower pressure will give more comfort but less speed and vice versa - personally I've never noticed much in the way of speed variance but I do feel the lack of comfort if a tyre is too firm.
I'm running the same tires as you at the same size; at 180 LBS (+24 lbs Bike/equip)
A Excel.docx based calculator says around 32 PSI front and 41 PSI rear - I personally run 34 PSI at the front and 42 PSI rear at that weight range (Split 45/55 weight distr)
For heavier riders at 210 LBS @ 24 Lbs bike equip; it goes to 37 F and 47 R. - Even if you're quite heavy in reality the PSI increase is not dramatic; I Believe that this calculator was aimed at the 15% recommended tire compression method, so it's not the minimum/max psi to ride.
As @MacB said, in reality while there is supposed to be a negative to running low PSI we do not feel it as much as we do when we run Too high psi. - 42c isn't a 25-32c tire, don't need to rock 'em hard anymore.
Edit: if you know your weight + bike weight + your weight distribution (45/55 or 60/40) then reply to me and i'll give you a more accurate PSI you could try.
A Excel.docx based calculator says around 32 PSI front and 41 PSI rear - I personally run 34 PSI at the front and 42 PSI rear at that weight range (Split 45/55 weight distr)
For heavier riders at 210 LBS @ 24 Lbs bike equip; it goes to 37 F and 47 R. - Even if you're quite heavy in reality the PSI increase is not dramatic; I Believe that this calculator was aimed at the 15% recommended tire compression method, so it's not the minimum/max psi to ride.
As @MacB said, in reality while there is supposed to be a negative to running low PSI we do not feel it as much as we do when we run Too high psi. - 42c isn't a 25-32c tire, don't need to rock 'em hard anymore.
Edit: if you know your weight + bike weight + your weight distribution (45/55 or 60/40) then reply to me and i'll give you a more accurate PSI you could try.
