Specialized Tarmac Disc

A race-focused road bike from 2020, made in 7 sizes from 44cm to 61cm.

Size

Stack 544 mmReach 384 mm

Geometry

Specialized Tarmac Disc geometry by frame size
Size
Fit
Stack (mm)How high the front sits	500	514	527	544	565	591	612
Reach (mm)How far forward the bars start	365	375	380	384	395	402	408
Stack ÷ reach Higher = more upright	1.37	1.37	1.39	1.42	1.43	1.47	1.50
Top tube (effective) (mm)Horizontal top-tube length	493	511	535	544	566	581	599
Seat tube angle Saddle position over the pedals	76°	75°	–	74°	74°	73°	–
Seat tube length (mm)Frame size reference	435	451	481	499	519	540	570
Head tube length (mm)Front-end height	105	115	126	143	163	190	210
Standover (mm)Clearance when you stop	730	740	755	775	795	826	850
Handling
Head tube angle Steeper = quicker steering	70°	–	71°	75°	72°	–	73°
Fork offset (mm)Fork rake	47	47	47	44	44	44	44
Trail (mm)More = steadier steering	71	63	58	58	55	55	52
Wheelbase (mm)Longer = more stable	969	973	975	978	990	1005	1012
Chainstay (mm)Shorter = snappier	410	410	410	410	410	410	410
BB drop (mm)More = lower centre of gravity	74	74	74	72	72	72	72
BB height (mm)Pedal clearance in corners	262	262	262	264	264	264	264
Front centre (mm)Room for your toes	571	574	577	579	591	606	613

Underlined values are calculated by BikeLens. A dash means the brand doesn't publish it.

A low, stretched position built for speed. Suits flexible riders who like to ride fast.

Size 54cm is lower and longer than 66% of the 218 road frames we track.

The closest road frames from other ranges, against size 54cm here.

Bikes with a similar fit, compared with size 54cm of this bike
Bike	Size	Stack	Reach
Giant TCR Advanced 0 PC2025Stack +1 mm, reach +4 mm	M	+1 mm	+4 mm
Merida SCULTURA 8000-E2021Stack −1 mm, reach +4 mm	SM/MD	−1 mm	+4 mm
Cervelo R52026Stack +1 mm, reach −1 mm	54	+1 mm	−1 mm
Cervelo S52026Stack −2 mm, reach same	54	−2 mm	same
Wilier Granturismo SL2024Stack +2 mm, reach −10 mm	S	+2 mm	−10 mm
Trek Madone SL 5 Gen 82027Stack +2 mm, reach same	MD	+2 mm	same