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 Most makers do not publish it, so I assume 15 mm and add 6 mm to the band, which on its own is enough to hold an answer at "probably" rather than "fits".
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 bar is than your saddle.
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
Mentech Chermin-R
Road · 7 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
- Mentech Chermin-R · Road · 7 sizes · integrated cockpit
- Geometry
- store.mentech.com, fetched 28 Aug 2026, re-checked, no differences
- Cockpit
- Generic stem and bar, assumed
- Solved with
- cover 15 mm (assumed), max spacers 40 mm (assumed), stem clamp centre 20 mm (assumed), so every verdict carries ±10 mm at the bar
- Sheet
- 6 September 2026 · 210 bikes, 43 makes, 1,262 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.| Size | Stack (mm) | Reach (mm) | Head angle (deg) | Seat angle (deg) | Head tube (mm) | Chainstay (mm) | Wheelbase (mm) | Standover (mm) |
|---|---|---|---|---|---|---|---|---|
| 44 | 511.6 | 352.7 | 71 | 75.5 | 100 | 406 | 955.4 | 727.5 |
| 48 | 524.6 | 364.4 | 72 | 75 | 110 | 406 | 962.6 | 742.3 |
| 52 | 539 | 375.5 | 73 | 74.5 | 130 | 406 | 963.9 | 767.9 |
| 54 | 546.6 | 383.3 | 73 | 74 | 140 | 406 | 975 | 787.5 |
| 56 | 557.8 | 389.8 | 73.5 | 73.5 | 150 | 406 | 980.2 | 803.7 |
| 58 | 575 | 399.2 | 73.5 | 73 | 170 | 408 | 997.7 | 824.8 |
| 60 | 600.7 | 410.6 | 74 | 72.5 | 195 | 408 | 1011.5 | 860 |
The table runs on to the right: 6 more columns after Reach. Scroll it sideways to read them.
The 54 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.
In the maker's words
Kept whole, as I read it off store.mentech.com.INTEGRATED one-piece bar/stem: Mentech Hindsight-Diting carbon handlebar.
Cockpit and seatpost, in the maker's words · 247 words
INTEGRATED one-piece bar/stem: Mentech Hindsight-Diting carbon handlebar. The frameset packing list is "1x Road Bike Frame, 1x Fork, 1x Integrated Handlebar, 1x Seatpost" (spec line "Integrated Handlebar Weight: 300g"), but the frameset page offers only Color and Size (44-60) options and states NO per-frame-size bar width or stem length, so stock_stem_length and stock_bar_width are null. Standalone bar page https://store.mentech.com/products/hindsight-diting-handlebar (USD 360, "Compatible With: Mentech Cherming Road Bike Frameset") sells sizes 34 / 36 / 38 / 40 / 42 (width in cm) and publishes a "Handlebar Geometry Chart" of width-stem combinations: 340-90/100/120, 360-90/100/120, 380-90/100/120/140, 400-100/120/140, 420-100/120/140 (mm). Width C-C 340/360/380/400/420; drop width C-C 370/390/410/430/450; drop 119/124/127/130/135 mm (by width); rise ("Rising") 20 mm; stem angle 10 deg; reach 75 mm; "Backsweep 65mm" (as printed - probably mislabelled); flare "2x15mm"; weight 320 g (400x100). Headset spacers supplied with the frameset: 10 mm x 2 and 5 mm x 2 (30 mm total; a maximum spacer stack is not stated); stem cover (headset top cover) height 10 mm or 20 mm. Headset bearings: upper 40x51.8x7 C1.5, lower 40x51.8x8 outer C3 / inner C1.5. Seatpost: carbon seatpost included, 76 g, offset 7 mm (spec line "Seatpost Offset: 7 mm" and table row Q "Seat Tube Offset 7"), length by table row P: 270 mm on sizes 44 and 48, 300 mm on 52-60 (row P is labelled "Seat Tube Length" a second time but the values 270/300 are clearly the seatpost); saddle clamp fits 7x7 mm or 7x9 mm rails.
Source is the brand's own store (store.mentech.com, Shopify, vendor Mentech). Source: official_store_html (brand's own Shopify store store.mentech.com, "Frame Geometry Chart" HTML table rows A-Q plus a geometry diagram image)
How I read the maker's table
The corporate site www.mentech.com (Dongguan Mentech Optical & Magnetic Co., Ltd.) has no bike geometry page and links to the store. NAMING: the store page title and spec block say "Chermin-R"; the URL slug and breadcrumb say "Cherming-R"; the bar page says "Cherming". File is named after the title spelling. SIZES: labelled 44 / 48 / 52 / 54 / 56 / 58 / 60 (nominal cm); the actual seat tube length (row A) is 440/460/485/510/530/555/590, so the labels are nominal, not measured. Rider height guide on the page: 7 sizes "fitting riders from 156-195 cm" (no per-size bands published). STACK/REACH DATUM: rows O "Frame Stack" and N "Frame Reach"; the diagram (https://store.mentech.com/cdn/shop/files/1920.jpg) draws the conventional dashed lines from BB centre to the top of the head tube, so BB centre to head-tube top is assumed; the page does not state it in words. Values are published to one decimal place and kept as published. The diagram shows a straight seat tube with the angle marked at the BB between the seat tube line and horizontal. HEAD TUBE LENGTH row C is head tube length in mm. TRAIL is labelled "Trail 25c" (computed with a 25 mm tyre, published by the maker so kept). STANDOVER is labelled "Standover 28" (assumed 28 mm tyre; maker does not say). Front centre not published (null). MODEL YEAR: the chart is undated; Shopify product created and published 2025-06-20 (bar product 2025-06-19), page live 2026-08-28, so model_year is left null. FRAME FACTS: Toray T800 + T1000 + T1100 carbon monocoque, frame 720 g (size 54, unpainted, excluding metal parts), fork 390 g +/-5 g (size 54), T47 77-A bottom bracket, 12x100 / 12x142 thru axles, flat mount 140/160 mm, UDH 1.0, max chainring 54/40T, max tyre 35C on 700C, mechanical and electronic groupsets, ISO 4210 tested; developed with the HKUST aerodynamics lab. Frameset USD 2,680 (six colours: Red Lava, Golden Desert, Grey Mist, Black Volcano, Cyan Lake, Sunset Glow); complete bike "Mentech Chermin-R Road Bike" listed from USD 5,150.
