Sole Power Scooters offer a number of machining and engineering services for your Lambretta. Many of the services we provide are conversions that have been pioneered by others before and some of the machining can be done at local shops near you…..the problem is that the quality of these services can be very suspect! We also offer a number of unique services and products and are always adding something new!
There are two questions you should ask if you’re going to use a local shop. First, do they have the ability to perform the job to the tolerances and specifications required? And second, do they care enough about your job to bother doing it to the proper specification? There are shops out there that will happily accept 0.003″ trueness on crankshafts without even thinking, whereas the goal you should be looking for is within 0.001″. Many shops also make their living working on motocross/off-road bikes, Harley-Davidsons or various other bikes. If they are unfamiliar with Lambrettas they may not know some important factors affecting their work. Here at Sole Power Scooters, Lambrettas are all we do, so we’ve looked at all of the different angles and philosophies regarding our beloved machines. You can rest assured we’ll get the job done right!
Cylinders are bored and honed to a quality cross-hatch finish. The modern recommended clearances are 0.002″-0.0025″ for quality standard pistons and 0.003″ for cheaper pistons or higher performance engines. We prefer the 0.003″ on all engines as it’s safer and requires less run-in time to break the engine in.
- $40 up to 1mm. Add $5 for each additional millimeter, (for example, a 57mm bored out to 62mm would be $40+20=$60)
Heads are reprofiled to suit the piston diameter and dome of the piston crown. Many Japanese pistons use a much shallower dome angle and to get the best performance must have the proper angle machined into the head to match. The compression ratio can also be changed to the desired ratio. If you’re unsure of what you want, we can help!
Shortening the cylinder top as required for various piston conversions. Connecting rod length, packing plates, etc are all taken into account to give the desired clearances.
Shortening the cylinder bottom as required for various piston conversions. Connecting rod length, packing plates, etc are all taken into account to give the desired clearances.
Piston is shortened as required. Normally only required when a Japanese piston is used with a 107 connecting rod.
Rebuild crankshaft with standard rod/pin/bearing assembly. Includes truing. LI/SX and GP. GP cranks can have 2 different pin sizes(22mm or 22.9mm) and only the 22m size is available from us currently. TIG welding the pins are preferred, but not necessary. Loctite-ing the pins (recommended by many shops and racers) can be done for no extra charge.
- $60, parts not included. Add $20 for welding of the pin.
Crankshaft is trued to within 0.001″. This is very important even if the bearing and rod assembly is still good.
Rebuild crankshaft with a yamaha rod, silver caged big-end bearing, big-end shims (recommended by many!), and pin. Requires machining before assembly. Available in 110mm and 115mm. This conversion mixed with a Wiseco forged piston has got to be one of the most rock solid set ups you can get for a Lambretta!! TIG welding the pin is highly recommended!