Stack and reach
How high and how far forward the top of the head tube is, from the bottom bracket. They are the two numbers that decide whether a frame can be set up like yours.
BB, or bottom bracket
The axle your cranks turn on, in the middle of the frame. Every number on this site is measured from it, because it is the one point that sits in the same place on every bike.
Headset cover
The little cap on top of the head tube, under your spacers. Most makers do not publish it, so I assume 10 mm and add 6 mm to the band beside every answer.
Stem clamp, and its centre
The collar on the steerer that your stem bolts to. I need the middle of it. Where a maker gives only the height, I assume halfway up and say so on the answer.
Steerer
The tube coming up out of the fork. The cover, the spacers and the stem all sit on it, and it is the thing a mechanic cuts to length.
Bar reach
How far forward the hoods sit from the middle of the bar. Two bars on the same stem can put your hands 20 mm apart, which is why I ask.
Setback
How far your saddle sits behind the bottom bracket.
Drop
How much lower your hands sit than your saddle. On a riser bar I count the bar's rise, so the drop is that much less than it is to the clamp.
Rails, and the rail centre
The two rods under your saddle, and the middle of the straight part of them. That midpoint is the point I use, because it is the one you can find with a tape.
The band
How far out I could be, in millimetres, and why. It is a straight sum of everything I had to assume rather than a clever average, so it errs wide on purpose.
wb, stand, trail
Wheelbase, standover and trail: how long the bike is, how high the top tube is where you straddle it, and how steady the steering feels. I show them against your bike, and I leave them out when the maker does not publish them.
est.
Estimated: a number I worked out rather than read off the maker's table. Anything marked this way can move if the maker publishes the real one.
Close Escape closes it. The measuring guide has the pictures. Open the measuring guide
Velobuild GF-002
Gravel · 5 sizes
The GF-002 on velobuildmall.com
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This is the bike I ride
No account is needed to read the table. Report a wrong number · Correct this bike
- Bike
- Velobuild GF-002 · Gravel · 5 sizes
- Geometry
- velobuildmall.com, fetched 22 Oct 2026, read off the maker's chart, re-checked, no differences
- Seat angle convention
- Calculated from Velobuild's table
- Cockpit
- Generic stem and bar, assumed
- Solved with
- cover 10 mm (assumed), max spacers 40 mm (assumed), stem clamp centre 20 mm (assumed), so every verdict carries ±10 mm at the bar
- Sheet
- 22 October 2026 · 879 bikes, 79 makes, 4,979 sizes in the catalogue
Geometry, every size, from the maker's table
The tinted row is the size drawn beside it. Press a size to draw it.The table runs on to the right: 6 more columns after Reach. Scroll it sideways to read them.
The M drawn to scale from the table, with no build on it. Stack and reach run from the bottom bracket to the top of the head tube; every size is solved from those two. One square is 100 mm.
The maker's cockpit
No stock cockpit I can name, so every size is solved on a generic stem and bar unless you choose one on the sheet.Generic stem and barAssumedNo bar is listed for this frame.
Frame facts
read off the maker's page: velobuildmall.com- Tyre clearance
- 50 mm
- Bottom bracket
- BB386
- Axles and brakes
- flat mount
- UDH
- not published
- Seatpost
- 27.2 mm round
- Frame weight
- 1100 g, size M
In the maker's words
Kept whole, as I read it off velobuildmall.com.The spec offers an "Integrated bar: 400/90 400/100 420/100 420/110 440/110 440/120mm" (one-piece, width/stem length; full carbon, 380g; no stem angle printed) or a "Separate bar and stem: Bar: 400/420/440mm, Stem: 80/90/100/110/120mm".
Cockpit and seatpost, in the maker's words · 38 words
The spec offers an "Integrated bar: 400/90 400/100 420/100 420/110 440/110 440/120mm" (one-piece, width/stem length; full carbon, 380g; no stem angle printed) or a "Separate bar and stem: Bar: 400/420/440mm, Stem: 80/90/100/110/120mm". No per-size stock bar or stem.
SOURCE: velobuildmall.com is VeloBuild's second store (UEESHOP, the same image host account UPBA916 as velobuild.com, whose pages the other VeloBuild files cite). Source: image_table (maker's own store velobuildmall.com; geometry published only as the description image
How I read the maker's table
Product page "2021 VeloBuild Carbon Fiber Integrated Gravel Bike Frame Hidden Cables" (model_year 2021 from the title; images uploaded Jan 2024). Rows as printed, under "SIZE IN(mm)": A "BB center to top of seattube"; B "Effectuve tio tube horizonta(l)" (sic; top_tube_effective); C "BB offset" printed with a minus sign (recorded as bb_drop, the drop); D chainstay length; E seat angle; F head angle; G front center; H head tube length; I fork offset; J reach; K stack (both to the head tube top in the drawing). No wheelbase, trail or standover printed. The S and M print the same front centre, 600, with different head tubes and angles: kept as printed, a possible slip. FORK OFFSET: the table prints I = 50 on every size; the page's spec image says the fork's "OFFSET: 45mm" (maker against maker; 50 kept from the geometry). Spec image: full carbon Toray T800; integrated seat clamp; frame 1100g (size M, clear coat, without metal parts); headset bearings 1-1/2 in x 7mm lower and upper; flat mount brake; BB386 (ID 46mm, width 86.5mm); Di2 and eTap compatible; EPS and latex moulding; full integrated cable routing; thru axle "M12*1.5*163mm" (frame) and "m12*1.5*130mm" (fork); max tyre 700C*50C; rotors up to 160mm; frame sizes XS/S/M/L/XL; fork 420g, steerer 300mm; seatpost 400mm / 27.2mm round, 230g.
Source: image_table (maker's own store velobuildmall.com; geometry published only as the description image https://ueeshop.ly200-cdn.com/u_file/UPBA/UPBA916/2401/18/photo/GF02-GEOMETRY-2.jpg, 950x780 px, headed "GEOMETRY GF-002 GRAVEL BIKE FRAMESET DISC BRAKE"; read by eye, image NOT stored)
