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thats what ive got too as everybody recomended it a specific to the malossi or polini rather than a converted standard head.santacama wrote:I use MMW (10,5:1 / 1,2 squish) without any problem.
cezeta wrote:thats what ive got too as everybody recomended it a specific to the malossi or polini rather than a converted standard head.santacama wrote:I use MMW (10,5:1 / 1,2 squish) without any problem.
Jerry at Readspeed did the head on my scoot and I can't fault it. On the Polinis I've built recently Harry Barlow has machined them.joeythescooterboy wrote:Al what head are you using and who did it?
Used a Malossi and a PM (for Malossi,) head and both pink like a pink thing. I've only used them as they were lying around once my Malossi snapped the exhaust stub.
The PM has lower compression than the proper Malossi head but the squish is all wrong due to the Malossi piston having a flatter crown profile than the Polini.
I have squished it and got 1.2mm at the piston edge but it goes down to 0.9mm at the inner edge of the band so it's obviously not working as it should. Instead of pushing the gas into the combustion bowl it's obviously trapping it at the edge.
Who does the best head for a Polini??
with corrected compression ratio.....so im told.....rather than just a skimmed and re profiled head. but dont take my word, im new to vespas after 20 years of dissing them so i do as im recomended to dosantacama wrote:cezeta wrote:thats what ive got too as everybody recomended it a specific to the malossi or polini rather than a converted standard head.santacama wrote:I use MMW (10,5:1 / 1,2 squish) without any problem.
¿¿¿¿¿¿?????? The MMW is a converted standard head.
