Fosse frame kit

Render of a Sturdy titanium frame in raw titanium, three-quarter view

Render of a Sturdy titanium frame in raw titanium, side view

Render of a Sturdy titanium frame in raw titanium, front view

Render of a Sturdy titanium frame in raw titanium, rear view

Titanium road frame, made to order in Somerset.

The Fosse is the culmination of hundreds of custom builds for our clients, distilled into a single, highly versatile road frame. Six sizes, each in three stack heights offer the chance to fine tune the fit for speed and performance but its core focus is for longer, endurance-friendly riding. A relatively low bottom bracket offsets the wider tyres now common on road builds, keeping it stable at speed without losing the agility you’d expect of a road bike. Finding your ideal fit is simple with our comprehensive fitting tools.

The Fosse showcases the latest engineering and manufacturing developments from Sturdy Cycles. We have replaced our 3D-printed junctions and components with fully redesigned, CNC-machined titanium alternatives, machined in-house and built to order at our Frome workshop. This new manufacturing approach brings a sharp, modern and minimal look, so every Sturdy remains a unique proposition: truly functional UK engineering, refined with handmade finesse.

Road grime and winter spray find their way into everything, so we’ve placed phosphor-bronze threads at the thru-axles and seatpost clamp, and each frame kit includes an Enduro headset backed by a lifetime bearing warranty. Paired with the included ENVE IN-Route Road carbon fork, the frame kit takes tyres up to 700×35mm. An optional titanium fork, launching in 2027, expands clearance to 38mm. Every frame kit also comes complete with an in-house CNC-machined titanium stem and seatpost. Customise your build with optional custom finishing, a complete 1X or 2X build kit, and our titanium crankset or accessory bundles.

Fosse Way: the Roman road that ran from Exeter to Lincoln, built in the first century AD. It still cuts an almost straight line across Somerset, a few miles from our Frome workshop.

Features

Lifetime warranty Warranty limited to the original owner.
Made in the UK Designed, Engineered, Manufactured and Finished at our Somerset workshop
ENVE IN-Route Road fork A carbon fork with fully internal routing for a clean front end, and room for 700×35mm tyres.
Titanium seatpost and stem Machined in-house from titanium to match the frame, and included in every frame kit.
SRAM, Shimano and Campagnolo compatible Built to suit any electronic shifting system.
Three stack options Low, Medium or Tall in every size. Pick the front end that suits how you ride, without a stack of spacers or a compromise stem.
Phosphor-bronze threads Bronze threads and bushes at the thru-axles and seatpost clamp, the places where titanium has a habit of seizing.
Enduro headset Enduro headset bearings, smooth and long-lived, with a lifetime warranty.
Interchangeable disc brake calliper mount Swap between 140mm and 160mm rotors without an adapter.
Ready for a titanium fork Our own titanium fork is on the way, due in 2027, taking clearance up to 38mm.

What's included

In the frame kit

Titanium Fosse frame, in your size and stack
ENVE IN-Route Road carbon fork
Titanium rear thru axle
Titanium UDH hanger with phosphor bronze inserts
Titanium seatpost, machined in-house
Titanium stem, machined in-house
Enduro stainless steel headset
Titanium bottle boss bolts

Optional extras

Fosse build kit, 2X £4,571.60 or 1X £4,511.60 inc VAT

Everything else you need for a complete road bike, chosen by us to suit the Fosse and shipped with the frame. After you order, you tell us your crank length, stem length, bar width and saddle height, and we put the kit together around you.

Titanium upgrade, +£674.01 inc VAT

Adds our titanium brake levers, jockey wheels and bar end plugs to the build kit, matched to the groupset. A small touch that makes a build feel finished.

Finishing

Every Fosse comes with a choice of standard finishes, included in the price. If you'd like something more personal, choose a custom theme (£600 ex VAT) or a bespoke finish (from £2,000 ex VAT), and we'll work out the details with you after ordering. Have a play with the options in the finishing selector. If you would like to see some examples of our custom Cerakote finishing then check out our past builds.

Every frame is made to order · Lead time approx 6 weeks

First frames to dispatch end of 2026

Frame parts in production

Specifications

Headset Enduro Stainless Steel - Lifetime Warranty
Bottom bracket T47-68 (68mm wide T47 threaded shell)
Rear axle spacing 142×12mm
Rear axle 167mm long, M12×1mm thread
Derailleur hanger UDH - Titanium Sturdy edition with phosphor-bronze threads
Brake mount Frame Adjustable 140mm or 160mm (Fork 140mm or 160mm)
Seatpost diameter 31.6mm
Design fork length 370mm
Cable routing Through the headset. Electronic groupsets only. Wire exit points for Shimano added if required.
Bosses 2 bottle cage mounts in the front triangle and mudguard mounts
Tyre clearance 35mm maximum recommended measured tyre width on a 700c rim (Frame 38mm - Enve Fork 35mm)

Geometry

Fosse frame kit: Low stack geometry
Measurement	XXS	XS	S	M	L	XL
Top tube (nominal) mm	490	510	530	550	570	590
Effective top tube mm	489	508	527	547	568	586
Stack mm	501.2	505.0	527.4	550.0	572.5	594.5
Reach mm	345.2	363.3	375.6	389.1	404.0	415.8
Head tube length mm	100	100	120	140	160	180
Head angle °	69.5	70.5	71.5	72.5	73.5	74.0
Seat angle °	74.0	74.0	74.0	74.0	74.0	74.0
Seat tube mm	448	458	488	519	550	580
Top tube slope °	8.5	7.5	6.5	5.5	4.5	4.0
Chainstay mm	411	411	411	411	411	411
BB drop mm	78	78	78	78	78	78
Fork rake mm	50	50	50	50	43	43
Fork length mm	370	370	370	370	370	370
Wheelbase mm	960	971	982	994	999	1012
Standover mm	717	723	749	775	801	826
Standard tyre	700x30c	700x30c	700x30c	700x30c	700x30c	700x30c

Fosse frame kit: Medium stack geometry
Measurement	XXS	XS	S	M	L	XL
Top tube (nominal) mm	490	510	530	550	570	590
Effective top tube mm	487	507	526	546	568	586
Stack mm	520.2	523.9	546.4	569.0	591.7	613.7
Reach mm	338.2	356.6	369.2	383.1	398.3	410.4
Head tube length mm	120	120	140	160	180	200
Head angle °	69.5	70.5	71.5	72.5	73.5	74.0
Seat angle °	74.0	74.0	74.0	74.0	74.0	74.0
Seat tube mm	468	478	508	539	570	600
Top tube slope °	8.5	7.5	6.5	5.5	4.5	4.0
Chainstay mm	411	411	411	411	411	411
BB drop mm	78	78	78	78	78	78
Fork rake mm	50	50	50	50	43	43
Fork length mm	370	370	370	370	370	370
Wheelbase mm	960	971	982	994	999	1012
Standover mm	736	742	768	794	820	845
Standard tyre	700x30c	700x30c	700x30c	700x30c	700x30c	700x30c

Fosse frame kit: Tall stack geometry
Measurement	XXS	XS	S	M	L	XL
Top tube (nominal) mm	490	510	530	550	570	590
Effective top tube mm	486	506	525	546	568	587
Stack mm	538.9	542.7	565.4	588.1	610.9	633.0
Reach mm	331.2	349.9	362.9	377.1	392.7	405.0
Head tube length mm	140	140	160	180	200	220
Head angle °	69.5	70.5	71.5	72.5	73.5	74.0
Seat angle °	74.0	74.0	74.0	74.0	74.0	74.0
Seat tube mm	488	498	528	559	590	620
Top tube slope °	8.5	7.5	6.5	5.5	4.5	4.0
Chainstay mm	411	411	411	411	411	411
BB drop mm	78	78	78	78	78	78
Fork rake mm	50	50	50	50	43	43
Fork length mm	370	370	370	370	370	370
Wheelbase mm	960	971	982	994	999	1012
Standover mm	755	761	787	813	839	865
Standard tyre	700x30c	700x30c	700x30c	700x30c	700x30c	700x30c

Not sure which size? Try the size selector, or compare the geometry.

Made in Somerset

Every Fosse and Drove is designed, engineered, machined, fabricated and finished in our workshop in Frome, Somerset. We've built hundreds of made-to-order bikes here, and keeping every stage under one roof means we know each frame from the first drawing to the day it leaves. Once you've ordered, Tom and Jack start work on yours.

Both frames are designed to exceed ISO 4210, the safety standard for bicycles, so you can ride them hard, and keep riding them for years.

Read more: Geometry and Handling · Materials

Questions

What happens after I order?

We'll be in touch by email within a working day to collect your fit details (crank length, stem length, bar width, saddle height) and talk through finishing. Nothing goes into production until we've agreed it all with you.

Which size should I choose?

All six sizes come in three stack heights, and no size is a compromise. The size selector and geometry comparison will point you to the right one, or you can size against your current bike. If you're unsure, email us.

How is finishing paid for?

The standard finish is included. If you choose a custom theme or bespoke finish, we agree it with you after ordering and send the balance as a separate invoice.

Do I need the build kit?

No. The frame kit is complete on its own, so if you already have parts you love or a builder you trust, you're all set. The build kit is there if you'd rather have everything from us, assembled and checked before it ships.

What's the difference between Fosse and Drove?

Fosse is our road frame, with room for 700×35mm tyres, made for long, quick days on tarmac. Drove is our gravel frame, with room for 700×50mm tyres for tracks, byways and rough lanes. Both share the same sizes, stacks and attention to detail.

How long will it take?

About six weeks from order. The first frames dispatch at the end of 2026.