Originally Posted by
ofajen
I haven’t seen that. The Silca calculator actually has the user select from various standard bike geometries (TT, road, gravel and MTB) with different F/R percentages and produces separate recommendations for front and rear. I’d be cautious about lowering the front too much as there is still braking to be done and out of the saddle work, both of which put more weight on the front.
Otto
You have not seen what? Silca gives you a choice of 50/50 for Road and 52/48 for TT and 53/47 for Mtb. I have been using Berto's 15% drop rule for almost 40 years. It works pretty well for normal tires but my testing showed supple tires can run a little higher pressures than his charts indicate but he did not have the quality of tires back then. The important point of his work is the differential in pressure F/R. I cannot see10-15 psi difference is some kind of risk.....like 90 psi rear and 75 psi front.
Clearly, you have not measured and do not believe me. This is what Zinn says
I’m convinced that anybody who says the weight distribution on a road bike should be 55 percent on the rear wheel and 45 percent on the front (or 50/50, or anything in the realm below 60 percent on the rear wheel) never actually measured it.
Don’t be surprised if it comes out 70/30.
https://www.velonews.com/gear/techni...compatibility/