DRT/SIP Clutch for Early Vespa Models – a reissued original design with modern features, adjustable spring tension, and high durability.
SIP SCOOTERSHOP, in collaboration with DRT specialist Denis Innocente, has reissued early Vespa clutches for which original replacement parts were practically no longer available. The DRT/SIP clutches fill this gap and combine dimensions faithful to the original with contemporary technology.
Precision CNC-machined components, a newly developed Base Plate, and modern design details ensure even force distribution, high load capacity, and smooth, controllable operation—even with performance-tuned engines.
- Reissue of Early Vespa Clutches
- Modern CNC technology and an optimized Base Plate
- Individually adjustable spring count for different performance levels
- Improved bearing arrangement and easier maintenance
The GS160 version features the Cone typical of these models, while the other versions are based on the corresponding model series. The number of springs in the basket and Base Plate has been increased to 12, 24, or 28, depending on the version, with diameters of 86 mm, 96 mm, or 115 mm. Standard springs for the LUSSO3/COSA Clutch are included.
For production-spec engines, it is sufficient to initially install only a portion of the springs, e.g., 6, 12, or 14 pieces. Depending on the power level, the number of springs can then be increased up to the maximum. This increases the contact pressure without making the Clutch unnecessarily hard to engage. A slight offset of the Spring Plates provides preload, prevents rattling, and makes operation smoother.
The previous bush with a needle cage has been replaced by a robust bronze bushing without needles. This simplifies replacement and overhaul. The thrust washer is modeled after modern Vespa models and increases operational reliability.
For clutches with Ø 86 mm and Ø 108 mm, the matching Clutch Gear Cog is included. For GS160 and PX clutches, the existing Gear Cogs can continue to be used. Depending on the model, Clutch Friction Plates and Release Plates must be ordered separately. Modified PX200 standard linings or DRT linings are recommended. In some cases, a slight adjustment to the Clutch Cover or the use of a Spacer may be necessary.
Technical Details
- Clutches for early Vespa models as well as selected GS160 and PX applications
- CNC-machined components
- Newly developed Base Plate
- Increased number of lead management units: 12 / 24 / 28
- Versions with Ø 86 mm, Ø 96 mm, and Ø 115 mm
- Compatible with LUSSO3/COSA standard springs
- Variable number of springs
- Bronze bushing instead of needle cage
- Modern Thrust Washer
- Matching coupling wheels for Ø 86 mm and Ø 108 mm included in the scope of delivery
- Original Gear Cogs can be used with GS160 and PX
Conclusion: A contemporary update to original clutches that are no longer available—smooth power transmission, a sturdy basket, and flexibly adjustable spring tension make the DRT/SIP Clutch the ideal solution for classic Vespa engines.
These products fit perfectly – SIP TIPS:
- Order new Clutch Friction Plates and separator plates as well, if they are not included in the package. Order several standard PIAGGIO springs to be able to vary the number of springs depending on engine power. A reinforced Cluster Circlip is also recommended.
Feedback from the community
“I’m using this clutch on my GS4. The DRT clutch disengages smoothly, is easy to modulate, and requires relatively little effort compared to a standard clutch. That’s exactly what makes it such a huge advantage.”
–Horst Binnig, Vespa Veterans Club Germany, 04/2010
“We use only DRT clutches for our Vespa stunt scooters. Under these conditions, any conventional clutch would fail quickly.”
–Robin Davy, Vespa Stunt Team Vespa Oldtimerfreunde Munich, 03/2010
“I’m absolutely convinced by this Clutch and have installed it in my Rally 210 with a large Carburettor and SIP Road. On the 2011 SIP Trip, I pushed our friend Toni—on his worn-out PX—kilometers up the Stelvio Pass—until my thigh gave out, but the Clutch didn’t. Perfect.”
–SIP Guy Max, SIP Trip Tuscany 2011