Am I too light for a steel bike?

Is your mass being increased by your velocity because it's approaching the speed of light, special relativity and all that stuff?

Comfort is subjective, I don't find soft, vague feeling tyres more comfortable personally. At 70kg I keep my 23mm pumped up to 110-120

IME manufacturers' recommendations err on the side of caution (too much rather than too little pressure). I'd suggest that 100 psi is far too high for your weight.

I have tried different pressures over the years and my starting point now for 25mm tyres is to put rider weight (kg) in the back and 5 psi less in the front.

Start with 50 front and 55 rear for 25mm, 5 to 10 psi more for 23mm.

The only time I had a snakebite puncture was last year, when I hit a sharp stone while braking on a steep descent on a back lane. The front tyre was a bit softer than usual, probably about 40 psi, and I was putting considerably more weight on the front tyre than normal. I'm confident that it wouldn't have punctured if the pressure had been what I usually use (~55 psi).

i weigh 80kg, I run 25s at 100psi, I would expect at 46kg 25s should be ok at 70psi or lower with no risk of pinch flats . I don't wonder that you feel every bump.

SwissTony wrote:

I'm running 26mm tyres at 85-90psi. Will let some air out and see how it goes, thanks.

Them's hard tyres.

Try 60 front & 65 rear and tweak either way in 5 psi increments.

Then when they need replacing fit some 28s.

I couldn't agree less, those pressures are way too low, just drop what you are currently riding by about 5psi, you can always drop it a bit more if you want 

I concur with Welsh Boy. And pressure way to low will cause pinch flats. If your hands feel the buzz get thicker padded gloves.

Yep