In brief
The BMW R 12 G/S Sumo isn't a BMW motorcycle: it's a custom bike built by the German workshop Classicbike-Raisch, which converted the R 12 G/S into a supermoto by fitting 17-inch wheels front and rear. The 1,170 cc boxer engine remains stock, producing 109 hp and 115 Nm; the wheels, tires, brake discs, exhaust, tail section, and controls have been changed.
The complete conversion costs €10,000 including VAT in Germany, TÜV inspection included, on top of the motorcycle's price: in Italy, the R 12 G/S starts at €17,900. Here you'll find what was changed and why, what remains unclear, what's needed to ride legally in Italy, and which accessories are currently fitted to the R 12 G/S.
- Who built it: Classicbike-Raisch, a workshop specializing in parts for BMW Heritage and Triumph Modern Classic motorcycles.
- What's changed: 21/17-inch wheels become 17/17-inch, with Pirelli Diablo Supercorsa SP tires and ABS rings remade for the new circumference.
- Price: €10,000 fully fitted; parts can also be purchased individually.
- In Italy: TÜV approval is valid in Germany. Here, modifications not listed in the registration document require inspection and testing at the Motor Vehicle Office (Art. 78 of the Highway Code).
The R 12 G/S Sumo is a custom bike built by a German workshop, not a BMW model
First, it's worth clarifying this, because the headline online makes it sound like a new model: BMW Motorrad doesn't sell a supermoto R 12 G/S and hasn't announced plans to make one.
Who are the Raischs?
Classicbike-Raisch is a family-run business led by three brothers and based in Rheda-Wiedenbrück, North Rhine-Westphalia. It develops and sells components for BMW Heritage family motorcycles (R nineT, R 12, R 18) and Triumph Modern Classics, and builds one-off motorcycles. The brothers raced supermotos on track, and according to the story published by Pipeburn, the Sumo was built for themselves, not commissioned by a customer: the idea was to bring the supermoto formula to a large-displacement BMW twin, and the R 12 G/S, released in 2025, provided the right base.
| Information | What we know | Level of confidence |
|---|---|---|
| Manufacturer | Classicbike-Raisch, Germany | Stated by the builder |
| Base motorcycle | BMW R 12 G/S (from 2025) | Stated by the builder |
| Components installed | Kineo rims, Pirelli Diablo Supercorsa SP tires, Wave discs, Unit Garage exhaust, Motogadget turn signals, M.View mirrors | Stated by the builder |
| Conversion price | €10,000 including VAT, parts, labor, and TÜV | Stated by the builder |
| Tire and disc sizes | Not disclosed | Unknown |
| Weight | Not disclosed | Unknown |
| Stock BMW version | No announcement | Does not exist |
About the date: the bike was covered by publications between October 8 and 12, 2026 (Moto.it, Visordown, inSella), based on the Pipeburn article. There was no unveiling at a trade show.
The engine and suspension remain stock; everything else is supermoto
The transformation focuses on the parts that determine how the bike meets the asphalt. The boxer engine isn't opened up, and the fork and Paralever remain BMW stock components.
| Item | Stock R 12 G/S | R 12 G/S Sumo |
|---|---|---|
| Engine | 1,170 cm³ air/oil-cooled boxer, 109 hp at 7,000 rpm, 115 Nm at 6,500 | Unchanged |
| Fork | 45 mm inverted, adjustable, 210 mm travel | Unchanged |
| Rear | Paralever with adjustable shock, 200 mm, shaft drive | Unchanged |
| Wheels | Wire-spoke, 21" front and 17" rear (18" rear with Enduro Package Pro) | Kineo tubeless wire-spoke wheels, 17" × 3.75 front and 17" × 5.5 rear |
| Tires | 90/90-21 and 150/70 R17 | Pirelli Diablo Supercorsa SP (sizes not disclosed) |
| Brakes | 2 x 310 mm discs, 2-piston floating calipers; 265 mm rear; ABS Pro | Wave petal discs front and rear; ABS retained with remade tone rings |
| Exhaust | Single-flow on the left, high-mounted silencer | Unit Garage 2-in-1 stainless steel, routed high along the tail, road-legal |
| Tail | Plastic license plate holder | Raisch short tail, turn signals moved close to the fender |
| Controls and details | Standard | Raisch levers, Motogadget m-Blaze Pin turn signals, M.View Spy 50 bar-end mirror |
| Protection | Catalog options | Engine guard, fork and shock guards, radiator grille, and fender retained |
| Weight | 229 kg stated in the inSella price list; 223.5 kg in running order, measured by the inSella test center | Not disclosed |
Stock R 12 G/S data: BMW Motorrad and Moto.it launch specifications; weight from the inSella price list and test center. Sumo data: Classicbike-Raisch via Pipeburn, as reported by Moto.it and inSella.
The 17-inch front wheel is at the heart of the transformation, and it's not just about looks
Switching from a 21-inch front wheel to a 17-inch one changes how the bike turns into corners, brakes, and reads speed. Three technical consequences that press releases don't explain.
1. Steering and contact patch
A smaller wheel has less inertia and a weaker gyroscopic effect: the bike tips into corners with less effort at the handlebars. In addition, a 17-inch road tire on a 3.75-inch rim offers a wider contact patch than a knobby or mixed-use 90/90-21 tire. That's why all supermotos are built this way. On the other hand, a smaller front wheel slightly lowers the front end and changes the setup: the Sumo's final geometry has not been disclosed.
2. ABS and traction control
The BMW system calculates each wheel's speed by counting the teeth on a tone ring. A 17-inch wheel has a different rolling circumference from a 21-inch wheel: with the stock ring, the control unit would see the two wheels spinning at incompatible speeds and might intervene unnecessarily or report an error. That's why Classicbike-Raisch supplies modified ABS rings with the conversion. It's the detail that separates a well-executed conversion from an improvised wheel swap.
3. Long-travel suspension on a road bike
The G/S retains its 210 mm fork travel and 200 mm rear travel. Under hard braking, the front end dives much more than on a road bike, and weight transfer is more pronounced. Racing supermotos are built around this compromise, but on a bike weighing over 220 kg, suspension setup matters: the BMW fork is adjustable, and tuning becomes part of the job.
About the tires: The Pirelli Diablo Supercorsa SP is a supersport tire approved for road use but also designed for the track. It performs best when warm and on dry roads; when cold and in the wet, it requires more care than a touring tire. Choose it with that in mind.
€10,000 conversion: the full bill starts at nearly €28,000
The turnkey kit price is clear; the rest depends on where you buy the bike and how much you want to do yourself.
| Item | Amount | Note |
|---|---|---|
| New BMW R 12 G/S, Italy | from €17,900 | Base list price |
| New BMW R 12 G/S, Germany | 16.990 € | Figure reported by Visordown |
| Complete Sumo conversion | €10,000 including VAT | Parts, labor, and TÜV inspection in Germany |
| Approximate total with the bike purchased in Italy | approx. €27,900 | Excluding shipping within Germany and Italian paperwork |
| DIY | Variable | All components are sold separately in the Classicbike-Raisch shop |
Complete kit or one piece at a time
The fact that the components can be purchased separately offers a middle ground: some will install only the short tail section and high-mounted exhaust, leaving the stock wheels in place; others will get a 17-inch wheel set to use as a second set for paved roads, switching back to the 21-inch wheel for off-road trips. In the latter case, remember that the ABS rings are attached to the wheels: each set needs the correct one.
In Italy, a TÜV inspection isn't enough: you need an inspection at the Motor Vehicle Office
The Sumo is approved for road use in Germany. A motorcycle registered in Italy must comply with the Italian Highway Code, and changing wheels and tires to sizes not listed in the registration document is a typical example.
What Article 78 says
Article 78 of the Highway Code requires an inspection and test at the Motor Vehicle Office when a vehicle's construction or functional characteristics listed in its registration document are modified. Replacing the 21-inch front wheel with a 17-inch one, along with tires of a different size from those approved, falls under these modifications. Anyone driving without having the vehicle inspected risks a fine of 430 to 1,731 euros and having their registration document confiscated, according to the text published by the ACI.
- Check before you buy. Ask your local Motor Vehicle Office or an automotive consultancy what documents are required to have wheels and tires that differ from those listed in your registration document inspected.
- Collect the component certificates. For the exhaust, the approval mark must be engraved on the part, and the certificate must be kept on board. For wheels and tires, you need the manufacturer's technical documentation.
- Have the vehicle inspected and update the registration document. Only after passing the inspection do the new sizes become legal for road use.
- Notify your insurer. An undeclared modification can cause problems in the event of an accident.
Not all parts affect your vehicle registration document in the same way. Levers, mirrors and turn signals can be replaced with approved components without inspection, provided they comply with the regulations (for mirrors, UNECE Regulation R81). Wheels and tire sizes, however, do require inspection. Always check with the Motor Vehicle Office before making changes. We are not lawyers or a vehicle registration agency: this is general guidance, not legal advice.
For an overview of upcoming rules for motorcyclists, read our in-depth article on the new Highway Code and motorcycles.
BMW had already built a boxer motard: the 2007 HP2 Megamoto
The Raisch idea has an official precedent. In 2007, BMW launched the HP2 Megamoto, derived from the HP2 Enduro, with 17-inch wheels and supermoto components. It remained in the lineup until 2012.
| Item | BMW HP2 Megamoto (2007) | R 12 G/S Sumo (2026) |
|---|---|---|
| Origin | BMW production model | Custom build by a specialist |
| Engine | 1,170 cc boxer, 4 valves per cylinder, 113 hp | 1,170 cc air/oil-cooled DOHC boxer, 109 hp |
| Torque | 115 Nm at 6,000 rpm | 115 Nm at 6,500 rpm |
| Weight | 178 kg dry | Not disclosed (the base bike weighs 229 kg ready to ride) |
| Front brakes | 2 x 320 mm floating discs, 4-piston calipers, no ABS | Wave discs, ABS retained |
| Suspension | 45 mm Marzocchi fork, Öhlins shock | Stock BMW 45 mm fork and Paralever |
| Price | 18.500 € (2007) | €17,900 + €10,000 |
What the comparison shows
The Megamoto was designed to be lightweight: almost 180 kg dry, with a specialist enduro frame. The Sumo starts with a heritage bike designed for road and dirt, much heavier, and focuses on character and style rather than weight. For riders looking for a boxer motard to push to the limit, the used Megamoto is the benchmark; for those who already own an R 12 G/S and want to give it a second personality, the Sumo offers a practical option. The full history of the G/S family, starting with the 1980 R 80 G/S, is in our article on the history of the GS.
HP2 Megamoto data: Moto.it test dated July 2, 2007.
It makes sense for those who ride the G/S on pavement, not for those who take it off-road
A 109 hp supermoto with long-travel suspension is a fun, unusual bike. It’s not an all-rounder.
- You ride the R 12 G/S almost exclusively on paved mountain roads
- A one-of-a-kind bike matters more to you than resale value
- You want a second set of road wheels to swap with the 21-inch front
- You have experience with supermotos or sport riding
- You ride on dirt roads or load the bike with luggage
- You often ride with a passenger: the short tail is a drawback
- You don’t want to deal with inspections and paperwork in Italy
- You’re looking for a lightweight supermoto: starting from a base weighing over 220 kg, it won’t be one
Accessories that fit the R 12 G/S today, Sumo or stock
The dedicated catalog for the R 12 G/S is still limited because the bike is new. We’ll tell you what’s designed for it and what’s universal, without claiming compatibility where none exists.
- Compatibility
- BMW R 12 G/S 2025-2026, model-specific fit
- Versions
- EVO with dimples, low-profile PRO, Silicone
- What they're for
- Keeps knees steady under braking and in corners, protects paintwork
- Price
- from €73.00
On a motorcycle ridden in the motard style, gripping the tank with your knees during hard braking and quick direction changes takes the strain off your wrists and arms. That's why the more aggressive EVO version is designed for the track.
- Capacity
- 40 liters, 55 × 30 × 25 cm
- Closure
- Patented magnetic roll-top
- Material
- Waxed canvas, PU trim, brass-colored buckles
- Mounting
- Universal, 4 anchor points on the sides of the tail
- Price
- 198,00 €
The Sumo's short tail section removes the long passenger seat and some of the anchor points: a 40-liter bag makes sense on the standard R 12 G/S, but not on the motard version. Waxed canvas also needs to be dried after rain: for heavy rain, a TPU bag is a better choice. Find out how much capacity to choose in motorcycle tail bags: 40, 50, 66, or 90 liters.
For other models from the Bavarian manufacturer, browse our collection of BMW motorcycle accessories. If you're considering bar-end mirrors like those on the Sumo, read our guide to folding mirrors and the UNECE R81 standard before buying.
Frequently asked questions about the BMW R 12 G/S Sumo
What is the BMW R 12 G/S Sumo?
Is the R 12 G/S Sumo an official BMW model?
How much does the Sumo conversion cost?
What wheels and tires does the Sumo have?
Has the R 12 G/S Sumo’s engine been modified?
Does the ABS still work with 17-inch wheels?
Can you ride the R 12 G/S Sumo on Italian roads?
Have the suspension components been changed?
How much does the R 12 G/S Sumo weigh?
Can you buy just a few parts for the Sumo?
Has BMW ever made a boxer supermoto?
Is the Sumo suitable for touring?
Which Endurrad accessories are compatible with the R 12 G/S?
Related guides
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Sources: Pipeburn, BMW R12 G/S «SUMO» by Classicbike-Raisch; inSella, October 12, 2026; Moto.it, October 8, 2026; Visordown, October 9, 2026; BMW Motorrad, R 12 G/S; Moto.it, R 12 G/S technical specifications; inSella, R 12 G/S test center; Moto.it, HP2 Megamoto test; ACI, Article 78 of the Highway Code. Photo of the R 12 G/S Sumo: Classicbike-Raisch. Data checked on October 16, 2026.
