I havent investigated the hubs on the stock wheels for the R and the X, but I wouldn't be at all surprised if they are identical.
The front brake calipers are the same, as are the stock pads. The only difference is a larger diameter rotor and a different caliper mounting bracket. The master cylinders appear to the identical (again, in contrast to others like the TE/SMS 630).
Yes, increased leverage results in the X having greater stopping power on the front wheel. In reading thousands of posts on these threads, it is uniformly considered a BAD thing in the dirt. The X brake locks the front wheel too easily for most (aggressive) riders. Also, and more important to some, the larger diameter X rotor places the caliper at increased risk of damage in a slide or crash - it is harder to protect.
The consensus it that the R brake is perfectly adequate, and more than adequate in the dirt. On the street, with X wheels and tires, with more rubber contacting the ground, the R brakes feel weak to some. This appears to be strongly correlated with their past history (street vs. dirt) and their expectations for performance, rather than linked to any real performance inadequacy.
As a counterpoint, several contributors here run knobbie tires on X wheels (I'm thinking of one in particular on a WR250X because he has a short inseam and likes the lower ride height on the X but wants full suspension travel). They have never reported that the X front brake is "too strong" in their dirt riding, but I didn't get the sense that they were aggressive riders.
1990 Honda NT-650 Hawk-GT
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