Cutting Piston for Reedvalve.
Posted: Tue Apr 18, 2017 6:24 pm
Been asked many times I know !
First ever attempt at a reedvalve in nearly half a century of stripping and building Lambrettas so now I need some sound advice.
Piston on con rod no rings and barrel on. Drawn a line to the extremities of the inlet manifold onto the piston at Bottom Dead Centre. Taken it out and permanet marked the area visible at BDC.
Got the tools, ready to cut BUT on this instance measure 3 or 4 times and ASK !
The top of the oval I have drawn is only about 5 or 6 mm from the bottom piston ring.
Is the vertical positioning of the hole or holes absolutely critical. I intend to cut an oval from the skirt also.
Something made me stop. It will take me a couple of minutes to cut and smooth so a short wait is not a problem. Many of the TS1 pistons I have seen have their cut outs level with the gudgeon pin.
In a nutshell, where do I cut ? I have read numerous threads but now I'm blinded by yhe ambiguity of them all.
First ever attempt at a reedvalve in nearly half a century of stripping and building Lambrettas so now I need some sound advice.
Piston on con rod no rings and barrel on. Drawn a line to the extremities of the inlet manifold onto the piston at Bottom Dead Centre. Taken it out and permanet marked the area visible at BDC.
Got the tools, ready to cut BUT on this instance measure 3 or 4 times and ASK !
The top of the oval I have drawn is only about 5 or 6 mm from the bottom piston ring.
Is the vertical positioning of the hole or holes absolutely critical. I intend to cut an oval from the skirt also.
Something made me stop. It will take me a couple of minutes to cut and smooth so a short wait is not a problem. Many of the TS1 pistons I have seen have their cut outs level with the gudgeon pin.
In a nutshell, where do I cut ? I have read numerous threads but now I'm blinded by yhe ambiguity of them all.