Had a GP 150 barrel bored to 63mm, also got a new piston to suit the bore .
Now the piston is the type that has the windows to mate with transfers or to put it another way the tranny holes in piston are cut out leaving the piece across the bottom of tranny window.
Now. Do i leave these as they are or do i cut these bits off and clean edges up.
Hope this makes sense and i know a pic would help but still aint sussed out how to post one.
what to do with my piston ?
Advice please anyone ???
Personally,as the piston was made that way,I would leave it as it is.
The piece across the bottom will be the strength of the piston skirt and if removed may cause the piston to crack near the top of the transfer window near the pin,in time.
The piece across the bottom will be the strength of the piston skirt and if removed may cause the piston to crack near the top of the transfer window near the pin,in time.
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Adam_Winstone
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Leave it as it is!
The later pistons, without transfer window skirt were cast with additional reinforcement thickening around the corners of the window. If you cut away the skirt then the additional pressure on the remaining skirt (top and bottom) tends to allow cracks to form from the sharp corners around the gudgeon pin boss, which can lead to long-term failure and crack off during running!!!
You will lose very little or nothing in the way of performance by leaving the skirt bridge as it is.
Adam
The later pistons, without transfer window skirt were cast with additional reinforcement thickening around the corners of the window. If you cut away the skirt then the additional pressure on the remaining skirt (top and bottom) tends to allow cracks to form from the sharp corners around the gudgeon pin boss, which can lead to long-term failure and crack off during running!!!
You will lose very little or nothing in the way of performance by leaving the skirt bridge as it is.
Adam
many thanks for the advice lads I will leave it as it is.
cheers, baz
cheers, baz