Front tire pressure

Point to note that running a low pressure with an inner tube and no bead lock raises possibility of ripping the valve out and a blow out.
Lower pressure helps with traction for sure, riding desert sands on my KTM used to run about 4 at the rear 8 psi at the front, would blast up any sand dune. My Honda 600RR (spit) road recommendation is 36/42, on track cold pressures on R10's of 32/30 (variable) gave more grip than I knew what to do with.

Mr. Rick said:

Yesterday I pulled out for a test drive around the block without checking the tire pressure and noticed a dramatic increase in front brake stopping power.

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If greater stopping power is present but wheel is not locked up, it is not due to a larger contact patch. It could be due to smaller diameter of tire giving an advantage through leverage. You would have to be extremely sensitive to notice a change this small, but hey, maybe the OP is.

When we ran our flattrack bikes on hard clay short tracks the track would be coated with a layer of rubber from our tires. They call it the blue groove. In these conditions I would run as low as 15 psi to increase the size of the contact patch. I am pretty sure some guys went lower. This is info that most guys wouldn't share. Secret go fast info ya know. Speeds were not that great so stability was not a problem.

Off the top of my head TT100 s the recommended pressure was 24 front 26 back with 4.10 s . Note than when paul smart raced on these tyres at imola on a ducati - they melted . Obviously many of you will be riding on much hotter road surfaces or indeed in much warmer climates with corresponding effect on tyre pressures..

Could low tire pressure equal better brakes?

Stephen Hill said:

Unless you were locking up your front wheel with the front tire at 26 pounds, I don't see how decreasing the tire pressure to 20 pounds is going to improve your braking. You will have increased the contact area on the road, but in terms of braking, it normally wouldn't make any difference.

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I agree.

XTINCT said:

If greater stopping power is felt but wheel is not locked up, it is not due to a larger contact patch. It could be due to smaller diameter of tire giving an advantage through leverage. You would have to be extremely sensitive to notice a change this small, but hey, maybe the OP is.

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This thing about the smaller diameter giving better leverage isn't as silly as I first thought.
with a front tire diameter of 25.75".
Radius is 12.875"
Radius is reduced by lower pressure, especially under the load of hard braking.
A difference of 1" ( this might be extreme) would equal a 7.77% shorter lever.
I think a difference of that amount could be noticeable by an experienced rider who paid attention to such things.

Put 100 pounds into a front tire, yank on that front brake and see what happens!
No . . . . please . . . . don't; bad idea.

"Contact patch" is not a matter of plane geometry; it is a dynamic problem - wriggly flexy hot rubber rolling over a rough irregular dirty surface. So . . . . IMO, much of the improvement in braking from lower pressures results from an increase in contact patch but also from the tire's improved ability to conform - dynamically - to the road's irregularities.

Then, for me, the real limit on low front pressures when you are braking hard while "going fast but at lower speeds" is squirm/imprecision while trail braking. The corollary is that I don't want to be braking hard with lower pressures while "going fast at higher speeds;" at real speed, that squirm 'll kill ya.

Steves and XTINCT, thanks for your comments re dirt riding and dirt track; I'd add that for me those ideas also are apt for lower speed twisty road/canyon riding. OldMikeW - yes, when the bikes got more powerful and heavier, the K81s did melt on the track - high psi wasn't enough to prevent overheating; that's when the Michelins took over - new rubber chemistry and less siping, good for clean smooth road surface. K81 is a great tire for dirty roads - lots of open area between tread blocks; you can see the evolution when you set a K70 beside a K81 - the K70, almost a trials tire pattern, from an earlier era with dirtier roads, the K81 a response to better later cleaner roads.