Answers on our bikes, sizing, orders, delivery and warranty, from the people who build them.
Since 1860Why PearsonBritain's oldest bicycle brand, making bikes since 1860. How we design, build and look after every one.16 answersOur customer care team works from the workshop in London, alongside the people who build every Pearson. Ask them anything.
Performance endurance road: frame, builds, wheels, mounts and sizes.
Explore the Forge
The Forge is built for riders who want genuine road-bike pace without giving up all-day comfort. Its geometry comes from thousands of real Pearson bike fits, so it stays fast and composed over long rides, sportives and big weekends.
As a starting point, this is the size most riders of your height and inside leg ride on the Forge. Where you fall between two sizes, your inside leg and the way you like to ride decide it, and a professional bike fit settles it for certain: we use your fit data to choose the frame and set up the contact points before we build your bike.
| Size | Rider height | Inside leg |
|---|---|---|
| 1 | 158-171 cm 5'2-5'7 | 73-79 cm 29-31 in |
| 2 | 167-178 cm 5'6-5'10 | 77-83 cm 30-33 in |
| 3 | 175-183 cm 5'9-6'0 | 81-87 cm 32-35 in |
| 4 | 180-190 cm 5'11-6'3 | 86-92 cm 34-37 in |
| 5 | 188+ cm 6'2+ | 91+ cm 36+ in |
Not sure? Try the Fit Finder, or ask us and we'll talk it through.
The Forge frame uses a blend of T800 and M40JB Toray carbon fibre. T800 is a high-strength carbon that gives the frame its durability and impact resistance. M40JB adds high-modulus rigidity in specific areas, increasing stiffness at the bottom bracket and head tube for efficient power transfer. The result is a frame that is fast and stiff without being harsh over long distances.
The Forge frame weighs 732g. The fork weighs 400g. Combined frameset weight is approximately 1132g. Both figures are measured at size 3.
System weight depends on the build tier. The Dura-Ace Di2 build (with ERE Genus II CLR 45 Carbon Spoke wheels) weighs 7.32kg. The Ultegra Di2 build (with ERE Genus II CL 45mm Carbon wheels) weighs 7.62kg. All figures are size 3 measurements.
The Forge has a maximum tyre clearance of 35c. Standard builds come fitted with Vittoria Corsa Pro tyres. The Forge is designed as a road performance endurance bike, so clearance is optimised for road and light gravel use rather than wider off-road rubber.
Yes. The ERE Genus II wheels supplied on all complete Forge builds are tubeless-compatible. Standard builds ship with inner tubes fitted. Converting to tubeless requires a tubeless valve kit, sealant, and tubeless-rated tyres. With Vittoria Corsa Pro tubeless tyres, the conversion is straightforward.
The Forge uses T47. Dura-Ace Di2 builds come fitted with a Ceramic Speed T47 bottom bracket. Ultegra Di2 builds come with a Hope T47 bottom bracket. T47 offers excellent durability, easy servicing, and wide compatibility with aftermarket options from both Shimano and SRAM.
Four builds: Shimano 105, Shimano Ultegra Di2, Shimano Dura-Ace Di2 and SRAM Force AXS. For frameset builds, the T47 bottom bracket and standard cable routing are compatible with a broad range of road groupsets from both Shimano and SRAM.
Dura-Ace Di2 builds come with ERE Genus II CLR 45 Carbon Spoke wheels. Ultegra Di2 builds come with ERE Genus II CL 45mm Carbon wheels. Both are tubeless-compatible carbon wheelsets. If you are purchasing the frameset only, wheel selection is your own.
The Forge uses performance endurance geometry across five sizes (1 to 5), developed from data gathered over 2,000 professional bike fits collected across 13 years. The geometry is shaped for an inclusive riding position: a shorter reach and slightly taller front end make the Forge accessible to a broad range of rider proportions, including those who need comfort over long distances without sacrificing performance.
The full geometry chart is on the Forge product page. We recommend using professional bike fit data to determine your correct size. If you have not had a fit, contact us on 020 3828 7696 or email care@pearsoncycles.com and we will talk you through the options before you order.
Yes. The Forge has hidden mudguard mounts at the fork crown and under the chainstay bridge, keeping the frame lines clean while allowing mudguards to be fitted for winter or wet-weather use. The Forge also has three bottle cage bosses: two on the down tube and one on the seat tube.
The Forge is certified to ISO 4210 safety standard. It is not UCI approved. For road sportives, gran fondos, and non-sanctioned events this makes no practical difference. If you are competing in UCI-sanctioned road races where UCI equipment approval is mandatory, the Shift 2.0 is our UCI-approved road model.
The Forge uses a T47 shell with a 68mm width. For Shimano cranks (24mm spindle): any T47 68mm bottom bracket in that spindle diameter. Hope T47 is a well-supported option that threads cleanly and services easily. Ceramic Speed T47 is the OEM fitment on Dura-Ace builds if you want factory-matched performance. For SRAM DUB cranks: a T47-to-DUB adapter unit is required.
If you are building the frameset with a groupset not listed in the standard complete bike options, contact us on 020 3828 7696 or email care@pearsoncycles.com and we can confirm compatibility before you order.
The Forge uses two hanger configurations depending on the groupset fitted. Shimano builds use a standard bolt-on hanger. SRAM builds use a direct mount dropout. Both types are available to order through Pearson: email care@pearsoncycles.com with your frame number and we will confirm the correct part. A spare hanger is included in the welcome pack with every complete bike.
The Forge comes with a Pearson-branded stem, seatpost, and handlebar. These are designed by Pearson but they are not proprietary parts. The steerer is a standard diameter, so any compatible aftermarket bar and stem will fit if you want to change them. Pearson replacement parts for the branded components are also available directly from us.
The one part that must be ordered through Pearson is the rear derailleur hanger. Hangers are model-specific and are not available through general bike shops. Email care@pearsoncycles.com with your frame number and we will sort a replacement.
The Forge uses M12 x 1 thread, 122mm at the front and M12 x 1, 166mm at the rear. The same specification applies to the Shift 2.0 and On&On Adventure. A replacement thru-axle set (front and rear) is available directly from Pearson for £20, and it covers all three models.
The On&On Race uses a different rear specification due to its UDH (Universal Derailleur Hanger) dropout, which requires a wider rear spacing.
Not what you needed? Ask the team and we'll answer you directly.
Contact us
