Have you ever wondered why Innocenti used a long stud and two nuts as the main engine bolt on a Lambretta, but Piaggio always used a proper bolt on a Vespa?
It can be annoying when you are working on scooters and one nut fastens all the way up while the other doesn’t have enough exposed thread left to even reach the Nyloc of the nut.
Two nuts do allow you to tap the stud both ways to loosen off the engine cones, but primarily I suspect it comes down to cost. A stud and two nuts is much cheaper than making a specific bolt, as Casa Performance have just found out.
The main advantage of a bolt is in the fitting of eccentric engine cones – which many people do on reedvalve kits in order to increase manifold/frame clearance. With this there is no chance of the offset cones spinning and going out of position (and therefore upsetting engine alignment) as you tighten up the bolt.
Casa Performance Lambretta engine bolt and offset cone set.
Casa Performance are offering this precision-ground bolt as part of their extensive range of performance & upgrade parts. The part number is X86/A and it’ll shortly be available from Casa Performance dealers Worldwide. If however you require a full kit complete with a pair of offset cones, wavy washers and a nyloc nut, Rimini Lambretta Centre have these available priced at £37.40 (€44.60).
Another advantage of the new engine bolt has only been realised now with the release of the new CasaCase with its vertical split to fit the crankshaft. With this new bolt – fitted from the kickstart side – it is now possible to easily replace a crankshaft with the engine in situ by simply undoing the nut on the flywheel side and splitting the engine casing.
Have you ever wondered why Innocenti used a long stud and two nuts as the main engine bolt on a Lambretta, but Piaggio always used a proper bolt on a Vespa?
It can be annoying when you are working on scooters and one nut fastens all the way up while the other doesn’t have enough exposed thread left to even reach the Nyloc of the nut.
Two nuts do allow you to tap the stud both ways to loosen off the engine cones, but primarily I suspect it comes down to cost. A stud and two nuts is much cheaper than making a specific bolt, as Casa Performance have just found out.
The main advantage of a bolt is in the fitting of eccentric engine cones – which many people do on reedvalve kits in order to increase manifold/frame clearance. With this there is no chance of the offset cones spinning and going out of position (and therefore upsetting engine alignment) as you tighten up the bolt.
Casa Performance are offering this precision-ground bolt as part of their extensive range of performance & upgrade parts. The part number is X86/A and it’ll shortly be available from Casa Performance dealers Worldwide. If however you require a full kit complete with a pair of offset cones, wavy washers and a nyloc nut, Rimini Lambretta Centre have these available priced at £37.40 (€44.60).
Another advantage of the new engine bolt has only been realised now with the release of the new CasaCase with its vertical split to fit the crankshaft. With this new bolt – fitted from the kickstart side – it is now possible to easily replace a crankshaft with the engine in situ by simply undoing the nut on the flywheel side and splitting the engine casing.
