Spoke to Mark Broadhurst via email and the port timings are the same whether the kit is MB or Scooter Center sourced. For maximum torque he recommends having the piston edge in line with the bottom of the two transfer ports, which *should* then have it sitting 0.5-1mm above the bottom of the exhaust port. If it is below the bottom of the exhaust port, the bottom of the port will need to be ground down until the piston is 0.5-1.0mm above it. Obviously this is all at BDC.
My piston is below the exhaust presently at BDC, so its time to get the Dremel out!
Just thought I'd update everyone with the answer to my earlier query.
Casa 185 / RT195 piston edge (deck?) to Exhaust port height
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Pompeydave
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I got the same problem with the piston slightly over the exhaust port. It's a different setup than the RT. I've got the squish to 1.35 so don't really want to mess that up. What difference will this make to the overall performance as basically it's slightly blocking the exhaust port?
Anyone?
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Adam_Winstone
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Piston crown above bottom edge of exhaust port is not an issue, the other way round is commonly considered bad practice. At least one well respected UK tuner has been grinding the port slightly lower than the piston crown for decades. I've run a number like that and have never had an issue.
Adam
Adam