If your Lambretta has a floppy brake pedal that moves side to side then either the pivot bush is worn out, or more seriously the pivot pin that the pedal sits on is worn out or corroded.
The Lambretta rear brake is a poor design start to finish, but it all gets much worse with the wrong length cable or a worn-out pedal pivot pin.
There are two practical solutions to this issue:
1. Buy a new bracket and pivot pin from someone like Scooter Restorations, grind-off the old bracket from the frame and weld on a new one.
Pros: You get a like-new replacement.
Cons: Welding to the frame means a full strip and repaint of that frame section at the very least. Welding on the new pedal support in the right place is tricky without a guide.
NOTE: It is also possible just to buy only a new pin, grind or cut through the tack-welds for the old one and weld the new one into the bracket, but this still means damaging any paint in the area.
2. Cut the worn part of the pin off and drill and tap the remaining part to accept one of the brake shoe pivot pins from a Lambretta engine casing.
Pros: You can do this at home if you own a drill and a tap and die set. In the future a worn pin can be unscrewed and replaced with a new one.
Cons: Access to do this is still tight and it is preferable if the legshields are removed.
Even though I have welding equipment I chose to use the second method for the ease and repeat-ability factor.
Pay attention that the replacement pin has a hexagon section for the spanner, so you need to cut the pin shorter by the same thickness at the hexagon to put the pedal in the same position as before. On this scooter, that also meant cutting the pin bracket slightly.
Your new brake pedal pivot is slightly longer than the original but it is possible to shim it before fitting the circlip. If and when it wears out it is easy to fit a new one.
Sticky
Credit to Jason Frost for telling me about this trick. This tip is one of many contained in the Complete Spanner’s Lambretta Manual .
