Sizing a race frame is a different exercise than picking a comfortable size off a general chart. Get it wrong and no amount of stem or seatpost adjustment fully makes up for it.
The Five ACT.01 Neo Sizes
The ACT.01 Neo is available in five frame sizes: 48, 51, 54, 56, and 58mm. Each size shifts stack, reach, and top tube length together as a set. Sizing up or down changes more than just standover height.
A Full Geometry Chart Is Coming
We're finishing a complete geometry table (stack, reach, top tube, head tube angle, chainstay length by size) for this page. Until it's live, the fastest way to get sized correctly is to send us the reach and stack of a bike that currently fits you well, or your height and saddle-to-bar-drop preference, to support@sandhill-sports.com, and we'll recommend a size before you order.
Why Frame Size Alone Isn't the Whole Story
Two riders on the same size 54 can end up in very different positions depending on stem length, spacer height, and saddle setback. Frame size gets you in the right range; fit is finished with the cockpit. If you're between two sizes, the deciding factor is usually reach and stack rather than standover clearance. On a race frame, you want to size for your position, not just for being able to stand over the top tube.
Questions Before You Order
If you're unsure, email us your current bike's brand/model/size or your key measurements (height, inseam, arm length if you have it) and we'll help you land on the right one before you buy.