RB20 piston wanted - any condition

[Knowledge]

Well, not quite any condition, but as long as it has a crown.

I have been contacted by a guy (Mike) in the States who wants to have a MB centre plug machined to suit his RB20 piston. MB say "send us your piston to match during machining", but Mike doesn't want to be without his scooter while the machining work is done on the other side of the world. Having drawn a blank with other options, he has contacted me.

If someone can provide an RB20 piston, either a knackered one or a loan of a good one, then this can be supplied to MB while Mike continues to ride his scooter.

It's a bit of a faff, but I guess it will all come good in the end with some help from other Lambretta riders.

[carlos fandango]

Which piston is it? I think they have used at least three makes.
The first one i had (kit No.19) had a blaster piston in it untill the chank gave up they replaced the crank and kit with a asso piston.
Russ

[shocky]

TBH its a bit pish poor MBD not having a template , jig or CNC programe for this as its a common enough piston

[Ian Hepworth]

TBH its a bit pish poor MBD not having a template , jig or CNC programe for this as its a common enough piston

There are about 6 different Yamaha domes on 66mm pistons. Stuff changes from year to year never mind model to model.

MB have got templates for most pistons in common use but there is always the first time to see a new piston in use.

[Knowledge]

Oh, so that explains why MB wanted Mike's piston, because it could have been one of six different types.

I'll suggest to Mike that he gets the head posted to him and machined in the US. Being a centre-plu head, it should be easy to hold in the lathe.

Thanks for the info.

[GP Kevo]

Have him send it to Deanspeed, who does all his machining in-house and is exclusively Lambretta and has many years experience.