You may be seeing customers come in for a bike fit on a bicycle equipped with road hydraulic disc brakes. If this is a returning customer who you already have fit documentation on, don't assume a direct transfer to this new bike. Regardless of the brake manufacturer, the lever design has increased the reach to the hoods compared to rim brake levers. Assuming the same effective top tube and stem, or handlebar X/Y, the actual contact point is now 10-15mm further out than if it were rim brake levers. It's unlikely this has been taken into account in the bike geometry or component selection, so you may need to compensate for this by changing out to a shorter stem.
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