44 Products
BMW Customization Workshop · Neuwied
BMW R45 conversion parts for Bobber & Café Racer
Lightweight, slim, and underrated: The BMW R45 shares its frame and many components with the R65, making it one of the most affordable entry-level bases for the world of boxer custom builds. Here you will find all the parts that we develop and install for the R45.
- Construction time1978–1985
- Displacement473 ml
- Performance26–35 hp
- ChassisTwinshock
Conversion by assembly group
Everything for your R45 conversion
From the tail to the electrics: Choose the assembly group – or scroll directly to all parts for the BMW R45.

Tail conversion
Rear frames, seats, fenders, and license plate holders – with TÜV certification.
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Front conversion
Triple clamps, headlights, speedometers, handlebars, and mounts for a clean front end.
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Exhaust
Complete exhaust systems and silencers made of stainless steel, many with ABE (general operating permit).
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Chassis
Struts, fork springs, damping systems, and suspension service.
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Electrical
Cable harnesses, ignition, regulators, and switches – assembled in-house.
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Engine & Performance
Overhaul, carburetor, ignition, and tuning on the test bench.
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All parts for the BMW R45
Why Sport Evolution
Parts from the converter, not from the retailer
Boxer specialist
For over 30 years, we have been building, restoring, and tuning BMW boxer and K-series models in Neuwied.
Registrable
TÜV Rheinland certified company. Many parts come with a technical report or ABE (General Operating Permit).
Custom test bench
Carburetor and fuel injection tuning on our Dynojet dynamometer.
Self-driven
Our parts are created on real concept bikes – tested on the road, not in a catalog.
Guide
The BMW R45 rebuild
Why the R45 is a great base for a custom build
The R45 was long dismissed as the "little sister." For custom builders, that is precisely its advantage: used models are relatively affordable, the frame is compact, and the weight is low. Because the frame, swingarm, and many components are identical to the BMW R65, a large portion of our twin-shock range fits directly.
The small boxer is particularly well-suited for a sleek bobber or a compact café racer – also ideal for shorter riders or as a first custom build.
BMW R45 profile
| Model | BMW R45 (Type 248) |
|---|---|
| Production period | 1978–1985 |
| Engine | Air-cooled 2-valve boxer |
| Displacement | 473 cc |
| Power | 26 hp or 35 hp (depending on version) |
| Rear suspension | Dual-arm swingarm with two shock absorbers (twin-shock) |
| Drive | Cardan shaft |
| Parts compatibility | Frame & many components identical to the R65 |
The most important conversion parts for the R45
- Rear conversion: Twin-shock rear frames and complete café racer rear conversion kits with TÜV certification.
- Fenders & license plates: Fender kits in high and low versions, license plate holders with certification.
- Electrics: Pre-assembled wiring harnesses for Acewell and Motogadget speedometers as well as universal wiring harnesses.
- Brakes & front end: Sport brake discs with ABE (general operating permit), speedometer bracket adapters for original triple clamps.
- Engine: Valves, OEM-quality starters, and breather kits.
Everything that fits the R45 can be found in the product list above. For engine overhauls, it is worth taking a look at our engine and transmission service.
More power for the small boxer
With 26 or 35 hp, the R45 is no powerhouse. Many customers therefore combine the conversion with an engine overhaul and a clean carburetor tuning. On our Dynojet dynamometer, we measure before and after and precisely adjust the mixture and ignition – this often results in noticeably more pulling power without sacrificing reliability.
FAQ
Questions about BMW R45
Can't find your question? Use our parts inquiry form – we will respond personally.
Do R65 parts fit the BMW R45?
In most cases, yes. The R45 and R65 share the same frame, swingarm, and many components. Rear frames, fender kits, and wiring harnesses for the R65 will therefore generally fit the R45 as well. If in doubt, our parts inquiry service is here to help.
Is the R45 suitable as a bobber?
Sehr gut. Der schmale Rahmen und das geringe Gewicht machen die R45 zu einer klassischen Bobber-Basis. Mit Twinshock-Heckrahmen, kurzem Fender und Kennzeichenträger seitlich entsteht eine sehr cleane Linie.
Are the conversion parts for the R45 eligible for registration?
Many of our parts are supplied with a TÜV certificate or ABE (General Operating Permit). As a TÜV Rheinland-certified company, we ensure from the very beginning of the development process that our products are eligible for registration. You can find information on which documents are included in the product details.
Can you also completely rebuild my R45?
Yes. In addition to individual parts, we build complete motorcycles in our workshop – from partial conversions to a finished concept bike. Simply get in touch via our contact form.