Clutch -SC, Wideframe, type Cosa2/FL- for genuine primary gear 67 tooth (helical) – Vespa 125, VN1T (60001-), VN2T, Vespa 150 VL1T, VL2T, VL3T, VB1T, ACMA 150 GL (1956-1958) – 23 tooth

Complete sport clutch for Vespa Wideframe models from 1954 onwards (VN1T (60001-), VN2T, VL1T, VL2T, VL3T, VB1T, ACMA (56-58)

The SC clutch is based on the mature and proven BGM Superstrong clutch for the PX models. It offers a modern and stable clutch technology for the 125-150cc Vespa Wideframe engines from 1954 onwards.

These already have a clutch cover with three fixing screws outside the outer radius of the cover. This corresponds to the modern standard of the Vespa PX models. The older models before 1954 (e.g. VM1T/VM2T) still have internal bolts. These do not fit large clutch types like the one shown here with Øa=115mm. We offer here our own type of clutch.

The big advantages of a conversion to the SC clutch are:

• Very easy to pull
• Very clean separation
• Quick and precise gear changes
• Very stable and perfect for tuned engines
• Incl. Spacer, gasket, washer, clutch nut, crescent and O-ring

FITTING
The SC clutch replaces the conventional clutch type, the Vespa from about 1954.
Thus usable in Vespa 125, VN1T (60001-), VN2T, Vespa 150 VL1T, VL2T, VL3T, VB1T, ACMA 150 GL (1956-1958).

MODIFICATIONS
Since the clutch has a larger diameter, small modifications to the engine housing and clutch cover are necessary for assembly. This is done by removing material from the drip nose (for the transmission oil) in the engine housing and clutch cover positioned at 12 o’clock. On the flat surface at the 9 o’clock position, also ensure sufficient clearance, if necessary remove some material here too. The set includes a spacer with seal. These ensure a greater distance between the clutch cover and the clutch, in order to compensate for the greater overall height of the clutch.

RETARGATIONS
More powerful motors require longer reduction ratios for the optimal use of their potential, otherwise the motor will literally turn into nothing. The Vespa Wideframe models all have a primary reduction ratio of 22/67 (clutch primary gear) ex works.

‘engine halves remain to variant’
The easiest way to get a better clutch and at the same time a longer gear ratio is to use our clutch SC6723L. This uses a clutch pinion with one tooth more (23Z instead of 22Z) and can be used with the original primary gear (67Z). This alone increases the final speed by about 5km/h. Ideal for light tuning or production engines that are driven with a high-torque exhaust system.

‘Engine halves must be changed to variant ‘
Engines that have been significantly increased in power (e.g. tuning cylinders, exhaust and carburetor) require a longer than the plug&play possible 23/67Z transmission ratio. Therefore not only the clutch pinion but also the large primary wheel in the engine is changed. For this it is necessary to disassemble the engine completely. A work which is however worthwhile and does not make more work in the course of a revision.

The Wideframe engines from approx. 1954 on have the more modern design of the primary drive, easy to recognize by the cover plates, which are fastened by 6 rivets. These primary drives can be equipped with primary wheels from bgm Pro as well as Bollag Motos and reinforced bgm primary repair kits.

Oblique or straight ?
The bgm Pro primary wheels for the Wideframe are always straight toothed. They offer the advantage that they do not exert any axial (lateral) forces on the crankshaft and auxiliary shaft. This effectively eliminates the risk of premature wear of the crankshaft bearing seats due to moving bearings. The straight toothed bgm Pro gear parts are manufactured with such a high precision that they run just as quietly as the original helical gears. In general, longer gear ratios can be achieved with the bgm Pro primary gears (62Z/63Z) than with the helical gears from Bollag Motos (64Z /65Z). Provided you keep one type of gearing (helical or straight), all offered pinion/primary wheel combinations are compatible with each other (a 23Z clutch can be used on the 62Z or 63Z primary wheel, or a clutch can be converted from 22Z to 24Z without changing the primary wheel).

Unlike most PX and Smallframe models, Wideframe engines do not simply use the same secondary transmission, but depending on the engine type there are different 3-speed and 4-speed transmissions which always consist of the same primary reduction of 22 teeth on the clutch pinion and 67 teeth on the primary wheel. It is therefore necessary to select the new primary drive to match the transmission used. With the selection we oriented ourselves at empirical values from the everyday life. A Rally 200 serves as a reference, which produces approx. 9-10 hp on the road and thus runs approx. 100km/h at 6,000 rpm.

The following primary reduction ratios are based on this performance, because the engines of the Wideframe have similar power and torque values at the rear wheel due to the power increase.50 x 8″) of the respective models, the following gradations result for performance-enhanced vehicles:

VL, VB (3-speed, 14-56, 20-49, 27-42)

• Clutch pinion 22 teeth(straight toothed)
• Primary gear 64 teeth(straight toothed)

(optionally also 23 / 65 helical toothed)

GS 150 VS1-5 At present, no changes to the primary are possible here due to the design of the clutch.

4-speed ACMA GL and reproduction (Pinasco) (13-57, 18-52, 23-47, 27,43)

• clutch pinion 23 teeth (straight toothed)
• primary gear 63 teeth (straight toothed)

(optionally also 24 / 65 helical toothed)

4-speed BGM Sport on 3rd gear50-8″ (12-57, 13-42, 16-38, 19-35)

• Clutch pinion 25 teeth (straight toothed)
• Primary gear 62 teeth (straight toothed)

FITS  :

• Vespa (A.C.M.A.) Vespa GL 150 (1958)
• Vespa (Douglas) Model 102L2 (VB1)
• Vespa (Messerschmitt) Vespa 150 T/1 (type 42, VL2T)
• Vespa (Piaggio) Vespa 150 (VB1T)
• Vespa (Piaggio) Vespa 150 (VL1T)
• Vespa (Piaggio) Vespa 150 (VL2T)
• Vespa (Piaggio) Vespa 125 (VN1T)
• Vespa (Piaggio) Vespa 125 (VN2T)