Factor OSTRO VAM geometryRoad · 2026 · 7 sizes, from 45 to 61

The Factor OSTRO VAM is a road bike available in 7 sizes, from 45 to 61. Stack ranges from 502 to 611 mm and reach from 360 to 409 mm. Its geometry is low and long, with a racing fit.

Stack502–611mm

Reach360–409mm

Head angle71.1–73.3°

Chainstay length405–410mm

Agile rear

What size OSTRO VAM do I need?

Enter the stack and reach of a bike that fits you well and we will tell you which size is closest and how to set it up.

Stack in mm Reach in mm Compare on Fitbikefy →

45S 502 · R 360

49S 503 · R 370

52S 523 · R 376

54S 542 · R 384

56S 565 · R 392

58S 587 · R 401

61S 611 · R 409

Enter your stack and reach to see which size fits you best.

Geometry chart by size

Measurements in mm and degrees, as published by Factor. The ones that matter most for choosing a size are in bold.

Size	45	49	52	54	56	58	61
Stack	502	503	523	542	565	587	611
Reach	360	370	376	384	392	401	409
Head angle	71.1°	71.1°	72.5°	72.5°	73.3°	73.3°	73.3°
Chainstay length	405	405	405	405	405	408	410
Wheelbase	970	969	971	985	987	1,006	1,022
BB drop	72	72	72	70	70	70	70
Fork offset	57	53	48	48	43	43	43
Trail	58	58	58	58	59	59	59
Standover	726	737	762	781	804	817	840
Seat tube (method not stated)	432	454	483	502	524	531	554
Seat angle (method not stated)	75.5°	74.5°	74.0°	74.0°	73.5°	73.5°	73.5°

Source: Factor official website · data from 11 Nov 2026.

Stack and reach of every size

Higher means a taller front end; further right means a longer reach. The blue dot is your search.

Character of each size

Compared with other road bikes. Further right means more of that quality.

Positionracing → relaxed

Steeringcalm → quick

Pedallingrearward → forward

Bottom brackethigh → low

Wheelbaselively → planted

Rear endstable → agile

Bikes with similar geometry (size 54)

The closest size of other road models, by stack and reach.

ModelΔ stackΔ reach

Ridley Helium Disc · S2024±0 mm±0 mmCompare →

Cervélo S5 · 542026±0 mm±0 mmCompare →

Pinarello DOGMA F 1 OF A KIND · 5002026+0 mm−1 mmCompare →

Pinarello DOGMA F EDIZIONE SPECIALE · 5002026+0 mm−1 mmCompare →

Pinarello Dogma F · 5002026+0 mm−1 mmCompare →

Pinarello Dogma F12 · 5302019+1 mm−1 mmCompare →

OSTRO VAM or Helium Disc? In size 54 they have exactly the same stack and reach (542 / 384 mm): the difference is in the frame and build, not the position.

Frequently asked questions

What size OSTRO VAM do I need?

It depends on your position, not just your height. The most reliable way is to compare the stack and reach of a bike that fits you with those of each size (from 502/360 mm in size 45 to 611/409 mm in size 61). The size finder on this page shows the closest size and the stem and spacers you would need.

What are the stack and reach of the OSTRO VAM in size 54?

Stack of 542 mm and reach of 384 mm.

Is the OSTRO VAM a racing or an endurance bike?

Racing. In size 54 its stack-to-reach ratio is at percentile 32 of road bikes: a low, stretched position.

Does it have the same geometry as the Helium Disc?

In size 54, yes: same stack and reach. If one already fits you, the same size of the other will put you in the same position.