Big Rock Road Bike Frame

The Big Rock Road Bike Frame is a carbon road frameset with an XS (49) frame of about 730 g and a fork of about 330 g (excluding metal parts), a T47 bottom bracket and compatibility with both fully internal and external cable routing. It comes in five sizes from XXS (45) to L (56), for riders who want to build up a light road bike themselves.

At a glance

• Category: Carbon road frameset (frame and fork)
• Brand: Big Rock (BIGROCK, China)
• Weight: frame approx. 730 g in XS (49); fork approx. 330 g (excluding metal parts)
• Bottom bracket and routing: T47; compatible with fully internal and external routing
• Material: Mitsubishi and Toray structural carbon fabrics
• Sizes: XXS (45), XS (49), S (52), M (54), L (56); 142 mm rear hub spacing
• Best for: Riders building a light carbon road bike who like bright paint and already know their size

Over the course of more than a year of extensive testing, bigrock rider "Da Ting" has won numerous awards, thoroughly validating the product. To cater to market demands, the frame design has been changed from an "external" to an "internal" routing, and the BSA standard has been updated to T47, making it compatible with both full internal and external routing systems.

In the pursuit of weight reduction, the frame's weight has gradually decreased from an initial 880 grams down to the current 730 grams. Through countless iterations of material layups and replacements, utilizing a variety of structural carbon fabrics from Mitsubishi, Toray, and others, the final result has achieved an impressive balance of lightweight and high strength, presenting a remarkable outcome.

Why build from a frameset?

Buying a frameset lets you choose your own groupset, wheels and cockpit, or move parts over from an old bike. The Big Rock road frame went through two years of road testing and changes: weight dropped from 880 g to 730 g (XS), the bottom bracket moved from BSA to T47, and it now works with both fully internal and external routing, so different drivetrain and routing setups can be used.

Who is it for?

This frameset suits riders with some bike knowledge who plan to build up or upgrade a frame. The smallest XXS (45) frame has 502.3 mm stack and 364.76 mm reach, so smaller riders also have a size option. For a cleaner cockpit, see the Big Rock Skyline 2 integrated road handlebar and check compatibility with us before ordering. If you are not familiar with building bikes, talk to us about the build before ordering.

Light carbon frame

Big Rock says many rounds of layup and material changes, using Mitsubishi, Toray and other structural carbon fabrics, brought the XS (49) frame down to about 730 g, with the fork at about 330 g (excluding metal parts). Big Rock's website also says its products mainly use Japanese Toray carbon, mixing T700, T800 and T1000 fabrics.

T47 bottom bracket

The frame moved from the earlier BSA standard to a T47 bottom bracket.

Internal and external routing

The frame was changed from external to internal routing and is compatible with both fully internal and external systems, so it can work with different cockpits and drivetrains.

Six colours

Jollymap offers Black, White, Pink, Turquoise, Chameleon Purple and Red (Green has been discontinued).

Sizes and geometry

Source: Big Rock official geometry chart and website product page (XXS = 45, XS = 49, S = 52, M = 54, L = 56). Big Rock does not publish a height chart.

Specifications

Brand / model	Big Rock road frameset
Material	Carbon, Mitsubishi and Toray structural carbon fabrics
Frame weight	approx. 730 g (XS / 49)
Fork weight	approx. 330 g (excluding metal parts)
Bottom bracket	T47
Cable routing	Compatible with fully internal and external routing
Rear hub spacing	142 mm
Sizes	XXS (45), XS (49), S (52), M (54), L (56)
Colours (Jollymap)	Black, White, Pink, Turquoise, Chameleon Purple, Red

Source: Big Rock official website product page and geometry chart. Items Big Rock does not publish (brake standard, steerer and headset spec, seatpost spec, max tyre width) are not listed; please check with us before ordering.

Jollymap advice

A frameset build has to match the bottom bracket, headset, seatpost and drivetrain. Before ordering, chat with us or message our Facebook page with your height, inseam, current bike's stack/reach and the groupset and bar you plan to use, and we will help confirm size and compatibility.

Frequently Asked Questions

How much does the Big Rock road frame weigh?

The XS (49) frame is about 730 g and the fork about 330 g (excluding metal parts), according to Big Rock's website. Big Rock does not publish frame weights for every size.

Where is Big Rock from?

Big Rock (BIGROCK, 大石) is a Chinese bike brand making road and mountain frames, handlebars, wheels and saddles. Its website says its carbon products mainly use Japanese Toray carbon.

What sizes are available and how do I choose?

Five sizes: XXS (45), XS (49), S (52), M (54) and L (56). Big Rock does not publish a height chart, so compare stack and reach with a bike that fits you, for example S (52) at 526.37 mm stack and 380 mm reach, or M (54) at 543 mm and 384.3 mm. Contact us if you are unsure.

What bottom bracket does the frame use?

T47. Big Rock says the frame moved from BSA to the T47 standard, so you need a T47 bottom bracket for your crankset.

Can the frame be run with fully internal routing?

Yes. Big Rock says the frame changed from external to internal routing and works with both fully internal and external systems; the actual setup depends on your handlebar and drivetrain, so check with us before ordering.

What carbon is the frame made from?

Big Rock says this frame uses Mitsubishi, Toray and other structural carbon fabrics; its website adds that the brand mainly uses Japanese Toray carbon, mixing T700, T800 and T1000.

Can I pair it with the Big Rock Skyline 2 integrated handlebar?

It needs checking first. An integrated bar must match the fork steerer diameter and headset; the Skyline 2 supports 28.6 mm (OD1) and 31.8 mm (OD2) steerers, and some bikes need a separately ordered special spacer. Please contact us before ordering to confirm the two are compatible.

 

Last updated: September 2026