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 Most makers do not publish it, so I assume 15 mm and add 6 mm to the band, which on its own is enough to hold an answer at "probably" rather than "fits".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 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
Mason Definition Integrale
Endurance road · 8 sizes
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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
- Mason Definition Integrale · Endurance road · 8 sizes
- Geometry
- masoncycles.cc, fetched 20 Oct 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
- 22 October 2026 · 686 bikes, 74 makes, 3,984 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) |
|---|---|---|---|---|---|---|---|---|
| 48CM | 520 | 375 | 71 | 74.5 | 120 | 415 | 985 | 723 |
| 50CM | 531 | 385 | 71.5 | 74.5 | 130 | 415 | 994 | 742 |
| 52CM | 540.5 | 386.5 | 71.5 | 74.5 | 140 | 415 | 999 | 758 |
| 54CM | 553 | 387 | 71.5 | 73.5 | 155 | 420 | 1009.5 | 778 |
| 56CM | 567.5 | 392.5 | 71.5 | 73.5 | 170 | 420 | 1019.5 | 794 |
| 58CM | 579 | 398.5 | 72 | 72.5 | 180 | 420 | 1024.5 | 808 |
| 60CM | 587 | 401 | 72 | 72.5 | 190 | 420 | 1030 | 823 |
| 62CM | 607.5 | 409.5 | 72.5 | 72.5 | 210 | 420 | 1040 | 846 |
The table runs on to the right: 6 more columns after Reach. Scroll it sideways to read them.
The 56CM 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.
Stock stem and bar per size50CM 90, 52CM 100 x 420, 54CM 110 x 440, 56CM 110 x 440, 58CM 120 x 460, 60CM 120 x 460, 62CM 120 x 460 (stem length x bar width, mm)
Frame facts
not read off the maker's page yet: masoncycles.cc- Tyre clearance
- not recorded yet
- Bottom bracket
- not recorded yet
- Axles and brakes
- not recorded yet
- UDH
- not recorded yet
- Seatpost
- not recorded yet
- Frame weight
- not recorded yet
In the maker's words
Kept whole, as I read it off masoncycles.cc.No cockpit with the frameset.
Cockpit and seatpost, in the maker's words · 71 words
No cockpit with the frameset. "Fully integrated routing that conceals cables and hoses within the cockpit", "Optimised for electronic shifting only", MASON x Deda AR fork; the page names no bar or stem. The chart's STEM row prints 80/90 (48CM), 90 (50CM), 100 (52CM), 110 (54CM and 56CM), 120 (58CM to 62CM) mm and its HANDLEBAR (OUTSIDE DIMENSION) row prints 400/420, 400/420, 420, 440, 440, 460, 460, 460 (mm, outside dimension).
OFFICIAL SOURCE: Mason Cycles product page for the Definition Integrale Frameset (URL slug definition-integrale-frameset-2025. Source: html table (official Mason Cycles product page "Definition Integrale Frameset", the "Full geometry chart" table in the page markup; fetched 2026-10-20
How I read the maker's table
"an alternative to the Definition3, with shortened chainstays, a new fork, and fully integrated routing"; "Lower crown height and stack height than Definition3"), eight sizes 48CM to 62CM, labels as printed. Some angle cells carry a degree sign in the markup (71.5º), stripped by the parser. Stack datum: the page's geometry diagram (/media/images/diagram-geometry.png, read for the datum only, not stored) draws stack and reach to the head tube top; no headset cover height is given. The trail row is labelled "TRAIL: 700 x 35", so tyre_width_mm 35. stock_bar_width is the HANDLEBAR (OUTSIDE DIMENSION) row as printed (mm); it is the bar's OUTSIDE dimension as the maker labels it, not centre to centre. Null on 48CM and 50CM where "400/420" is printed; stock_stem_length null on 48CM where "80/90" is printed. FORK CROWN HEIGHT 367; frame weights 1650gr to 1880gr. integrated_cockpit is false: the routing is integrated, no one-piece cockpit is named. Max tyre clearance "700C x 35mm [approx. 700C x 32mm with mudguards]". Model year: not printed in the chart; the URL slug carries 2025 and Bike Insights files it as 2026, so model_year is left null.
Source: html table (official Mason Cycles product page "Definition Integrale Frameset", the "Full geometry chart" table in the page markup; fetched 2026-10-20, HTTP 200)