Giro
Register II MIPS
Everyday adult helmet with MIPS and a simple dial fit.
Universal Adult, 54–61 cm
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Specialized Hybrid frame
Specialized Sirrus Size Chart
Sirrus and Sirrus X share one published sizing chart, and the Sirrus X 4.0 frame runs XXS to XL on that ladder. The chart itself adds XXL, which the Sirrus X 6.0 builds; this page names the frame each standover was read from rather than borrowing one.
- Frame sizes
- XXS–XL · 6 sizes
- Rider height
- 4'8"–6'4"
- Height (cm)
- 142–193 cm
- Stack / reach · M
- 635 / 382 mm
Sirrus X 4.0 size finder
Which Sirrus X 4.0 size covers your height?
Height gives you one size, or two when the published height ranges overlap. Stack, reach, and standover settle the overlap.
ft
in
Enter your height and the Sirrus X 4.0 size that covers it is marked in the tables below.
How to measureHeight gives the starting size. Standover and reach confirm it.
Height ranges
Where each size starts and ends
Height ranges for every Sirrus X 4.0 size, 138 to 197 cm overall. XXS: 142 to 150 cm. XS: 150 to 158 cm. S: 155 to 165 cm. M: 165 to 175 cm. L: 175 to 183 cm. XL: 183 to 193 cm.
- XXS142–150 cm
- XS150–158 cm
- S155–165 cm
- M165–175 cm
- L175–183 cm
- XL183–193 cm
138 cm168 cm197 cm
Size chart
Sirrus X 4.0 size by height
Rider height is Specialized's published Sirrus and Sirrus X chart. Specialized publishes no rider inseam for this family, so the table shows height only.
Size
Height
Height cm
Inseam
Fit note
XXS
4'8"–4'11"
142–150 cm
–
Smallest Sirrus size, with the lowest standover in the ladder at 700 mm.
XS
4'11"–5'2"
150–158 cm
–
Reach grows 16 mm from XXS while stack grows 3 mm, so this step lengthens the cockpit rather than raising the front end.
S
5'1"–5'5"
155–165 cm
–
28 mm more standover than XS; M to L is the largest step at 32 mm.
M
5'5"–5'9"
165–175 cm
–
Most riders start here. Stack and reach above are for this size.
L
5'9"–6'0"
175–183 cm
–
Reach grows only 4 mm from M while stack grows 16 mm, so the front end rises without much extra cockpit.
XL
6'0"–6'4"
183–193 cm
–
Tallest size on the Sirrus X 4.0 frame, with the highest standover at 831 mm.
XXS
4'8"–4'11"
142–150 cm
Smallest Sirrus size, with the lowest standover in the ladder at 700 mm.
XS
4'11"–5'2"
150–158 cm
Reach grows 16 mm from XXS while stack grows 3 mm, so this step lengthens the cockpit rather than raising the front end.
S
5'1"–5'5"
155–165 cm
28 mm more standover than XS; M to L is the largest step at 32 mm.
M
5'5"–5'9"
165–175 cm
Most riders start here. Stack and reach above are for this size.
L
5'9"–6'0"
175–183 cm
Reach grows only 4 mm from M while stack grows 16 mm, so the front end rises without much extra cockpit.
XL
6'0"–6'4"
183–193 cm
Tallest size on the Sirrus X 4.0 frame, with the highest standover at 831 mm.
Start with height. If two sizes overlap, use cycling inseam to choose.How to measure
Geometry
Sirrus X 4.0 geometry by size
Stack, reach, and standover for every Sirrus X 4.0 size, read from Specialized's geometry table. XXL is not on this frame's ladder, so it is not shown here.
Size
Height
Stack
Reach
Standover
XXS
4'8"–4'11"
587 mm
355 mm
700 mm
XS
4'11"–5'2"
590 mm
371 mm
722 mm
S
5'1"–5'5"
606 mm
376 mm
750 mm
M
5'5"–5'9"
635 mm
382 mm
778 mm
L
5'9"–6'0"
651 mm
386 mm
810 mm
XL
6'0"–6'4"
672 mm
398 mm
831 mm
XXS
4'8"–4'11"
- Stack
- 587 mm
- Reach
- 355 mm
- Standover
- 700 mm
XS
4'11"–5'2"
- Stack
- 590 mm
- Reach
- 371 mm
- Standover
- 722 mm
S
5'1"–5'5"
- Stack
- 606 mm
- Reach
- 376 mm
- Standover
- 750 mm
M
5'5"–5'9"
- Stack
- 635 mm
- Reach
- 382 mm
- Standover
- 778 mm
L
5'9"–6'0"
- Stack
- 651 mm
- Reach
- 386 mm
- Standover
- 810 mm
XL
6'0"–6'4"
- Stack
- 672 mm
- Reach
- 398 mm
- Standover
- 831 mm
XXS4'8"–4'11"
Stack587 mmReach355 mmXS4'11"–5'2"
Stack590 mmReach371 mmS5'1"–5'5"
Stack606 mmReach376 mmM5'5"–5'9"
Stack635 mmReach382 mmL5'9"–6'0"
Stack651 mmReach386 mmXL6'0"–6'4"
Stack672 mmReach398 mm
How neighboring sizes compare
If two sizes both fit, compare reach and standover rather than assuming the larger size is more comfortable.
How to measure a bike frame- Size stepStackReachStandover
- XXS → XS+3 mm+16 mm+22 mm
- XS → S+16 mm+5 mm+28 mm
- S → M+29 mm+6 mm+28 mm
- M → L+16 mm+4 mm+32 mm
- L → XL+21 mm+12 mm+21 mm
Starter kit
Helmet, light, lock, bottle, and a pant-leg strap. Size the bike here; buy the complete adult bike at a shop.
NiteRider
Swift 300
Compact USB headlight for commuting and dusk rides.
Handlebar mount, 300 lumens
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Kryptonite
Evolution Mini-7 with 4′ cable
Hardened U-lock plus a cable for wheels or a locked-together pair.
Fits most road, gravel, and hybrid frames
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CamelBak
Podium Chill 21 oz
Insulated squeeze bottle for everyday rides.
Fits a standard ~73 mm cage
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Green Guru
Narrow pant-leg strap
Upcycled inner-tube strap that keeps a pant leg off the chain.
Adjustable hook-and-loop, about 16 in long
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Bike size calculator
Find your Specialized Sirrus X 4.0 size
Enter your height and inseam for a Specialized hybrid bike, then compare the result with this Sirrus X 4.0 chart.
Sizing notes
Why height alone is not enough
Riders with the same height can need different sizes because inseam, torso length, flexibility, and preferred handling differ.
3 checks
Sirrus stack climbs 85 mm from XXS to XL while reach grows only 43 mm, so the front end rises about twice as fast as the cockpit lengthens. That is what makes it an upright fitness bike rather than a road frame.
Standover climbs 131 mm across the ladder, from 700 mm at XXS to 831 mm at XL, and the largest single step is 32 mm from M to L.
The published Sirrus chart runs one size past this frame: Specialized lists XXL for 193–198 cm, and the Sirrus X 6.0 is the frame that builds it.
Sources
Confirm the exact bike after you have a starting size
Every number on this page comes from the sources below. Check the exact model year there before you buy.
Data reviewed:
Compare
Compare before buying
A size label does not mean the same thing across brands. Compare published geometry before you choose.
Related guides
More Specialized and hybrid sizing
Once you have a starting size, compare this frame against the Specialized chart and the hybrid guide.
Specialized bike size chart
Compare Sirrus X 4.0 against broader Specialized size guidance.
Hybrid bike size chart
Check hybrid sizing by height and inseam before choosing a frame.
Questions
Sirrus X 4.0 size chart FAQ
Short answers for Specialized Sirrus X 4.0 sizing.
What size Specialized Sirrus should I ride?
Start with the Specialized height band: XXS for 142–150 cm, XS for 150–158 cm, S for 155–165 cm, M for 165–175 cm, L for 175–183 cm, and XL for 183–193 cm. Then confirm standover for the size you land on.
Is the Specialized Sirrus the same size as the Sirrus X?
Specialized publishes one sizing chart for both, so the XXS to XXL height bands carry across. The frames differ, so confirm stack, reach, and standover on the model you are buying.
What size Sirrus fits a 175 cm rider?
175 cm sits at the top of the M band of 165–175 cm and inside the L band of 175–183 cm. M carries 635 mm of stack and 382 mm of reach; L adds 16 mm of stack and 4 mm of reach with 32 mm more standover.
Does the Sirrus come in XXS?
Yes. Specialized publishes XXS for 142–150 cm, and the Sirrus X 4.0 builds it with 587 mm of stack, 355 mm of reach, and 700 mm of standover.
How tall is a Sirrus M for?
Specialized publishes Sirrus M for riders from 165–175 cm (5'5"–5'9"). It carries 635 mm of stack, 382 mm of reach, and 778 mm of standover.