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 Most makers do not publish it, so I assume 10 mm and add 6 mm to the band beside every answer.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
Hongfu FM188
Gravel · 4 sizes
Sign in and add the bike you ride, and this table will say what each size needs for your position.
Sign in
This is the bike I ride
No account is needed to read the table. Report a wrong number · Correct this bike
- Bike
- Hongfu FM188 · Gravel · 4 sizes · integrated cockpit
- Geometry
- hongfu-bikes.com, fetched 20 Oct 2026, read off the maker's chart, re-checked, no differences
- Seat angle convention
- Calculated from Hongfu'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 / 55 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 from the maker's words, not a table: hongfu-bikes.com- Tyre clearance
- 700c x 45 mm, 650b x 2 in
- Bottom bracket
- not recorded yet
- Axles and brakes
- 12x100 / 12x142, flat mount
- UDH
- not recorded yet
- Seatpost
- 27.2 mm round
- Frame weight
- 1190 g
In the maker's words
Kept whole, as I read it off hongfu-bikes.com.SOLD AS A FRAMESET by an OEM factory ("I want to inquire"); no bar or stem is specified, so stock stem and bar are null.
Cockpit and seatpost, in the maker's words · 112 words
SOLD AS A FRAMESET by an OEM factory ("I want to inquire"); no bar or stem is specified, so stock stem and bar are null. The catalogue page renders the frame with a one-piece integrated bar and gives "Headset: 1-1/2" * 1-1/2" (FSA)", the specification of a fully internal (through-headset) routed front end, hence integrated_cockpit true; no bar geometry is published. Seatpost 27.2 mm round. Frame: T800/T1000 carbon (catalogue) or Toray T800 UD (2023 page text), BB86 (catalogue) or BSA/BB86 (2023 page), flat mount, 142x12 rear and 100x12 front thru-axles, 140 mm rotors, max tyre 700c x 45 mm or 27.5 x 2.0 in; frame 1070-1190 +/-40 g, fork 477 +/-15 g.
SOURCE: www.hongfu-bikes.com is the maker's own site (HongFu Sports Equipment Co., Ltd). Source: image_table (the maker's own product page carries the geometry as a catalogue page image in the description
How I read the maker's table
Two pages describe the FM188: /products/4.html ("FM188 Internal cable routing", Size: XS, S, M, L; no image) and /products/72.html ("New CX Full carbon gravel bike frame FM188", published 2023-10, which carries the geometry image); the image's spec block (headset 1-1/2" x 1-1/2" FSA, tyre 700c x 45 mm, seatpost 27.2, BB86, sizes XS-L) matches page 4, while page 72's own text says "Headset: top 1-1/8", down 1-1/2"" and "Available sizes: 50/52/54/56/58/60cm", which does not match the table it shows (a copy-paste from another frame, flagged here, not used). TABLE LEGEND (from the lettered diagram): A = seat tube, BB centre along the tube to its top; B = top tube, horizontal (top_tube_effective); C = Reach and D = Stack, from the BB centre to the head tube top; E = head tube; F = seat angle; G = head angle; H = front centre, BB centre to front axle; I = fork length 400 every size (not a schema field); J = BB drop (70 on XS/S, 68 on M/L); K = fork offset 45; RC = chainstay 430; WB = wheelbase. SIZE LABELS: the table's XS/S/M/L with the red cm sizes printed beside each row (49, 51, 55, 59), written "XS / 49". NOT PUBLISHED: standover, trail (null). MODEL YEAR: not printed; image uploaded 2023-10-20; model_year null. Bike Insights lists no FM188 (brand page read 2026-10-20). No Panda Podium, Geometry Geeks or 99 Spokes request was made.
Source: image_table (the maker's own product page carries the geometry as a catalogue page image in the description: https://www.hongfu-bikes.com/upload/image/20231020/1697784954809604.jpg, 1937x1300 px, catalogue page 14 "NEW GRAVEL FRAME FM188" with spec block, lettered diagram and table; numbers read by eye, image NOT stored)
