Originally Posted by
PeteDman
Found the link below and was wondering what your thoughts are. My bike and I weigh 195 lbs (on 25c) and based on using the Race Bike ratio, my front tire should be around 67 psi (seems really low). What do you think?
http://www.bikequarterly.com/images/TireDrop.pdf
Personally, I think there's a lot of merit to the thinking behind that article, and have certainly shared it a bunch myself -- BUT -- I'm not on board with the more unbalanced tire pressure ratios, like 40%/60% or even 35%/65%. The reason being that if you climb or descend steep hills, the weight distribution shifts away from that static measurement a lot.
I think it's better to stick to 45%/55% for road bikes. That's enough to get you more hand comfort and pinch flat protection in the rear. After maybe 5 years doing it, I've had no pinch flats whatsoever with the calculated tire pressures. Concerns about increased rolling resistance went away when I noticed that I actually felt fresher after long rides, rather than being "beat up".
Here's what I use for a total weight of 190-200 lbs, listed as front/rear:
28mm: 65/80psi
30mm: 60/70psi
37mm: 40/50psi
42mm: 32.5/40psi