SSS Kiwi has the right idea in this thread Bike pistons when found will be lighter stronger and allow much higher revs with less load than most car sourced pistons.

I have used Honda XR500 Pistons in a L series 2.3 litre stroker rally engine and being so light they allowed that engine to rev about a 1000 RPM more than normal L series 2400's as people refer to them as, Most were not actually 2400cc more like 2290cc,Therefore check either Wossner or Wiseco catalogs for diameters but I do not believe they give crown heights in most cases but do give pin sizes so some research could be worthwhile

Yes, using the stock head gasket, 1/2 mm thickness of piston dome maybe will result in good quench with H89 -- or other closed chamber head. if so you could run on premium pump fuel. Not only does this gain power, but increases the fuel economy more than the increased cost of fuel. Win win

Also save on pistons, use less expensive gasket, no machining costs

An old thread I know, but I was thinking about it again. I reckon you could use the Daihatsu HD-E piston without modification, if the crown is 0.5mm above the deck it's still within the gasket height. Should get some good compression, I calculate 12 and a bit with a stock head and gasket.

how about the gemini pistons they are almost flat tops and
some available in 28.2mm com height

How do you read the +0.5? To me that says the dome is 0.5mm because the pistons with dishes have a -ve there, I'm guessing though. Some photos of the actual piston would be good.

Edit: I found a pic here http://daiforum.net/viewtopic.php?f=6&t=176, seems to agree with my guess.

Am a NA man..

Have had my time in boosted cars and heaps of fun but just love a crisp revving NA motor..

No idea if the triple pistons are suited, just remembered they were 79mm, no idea on pin dia and height..

Deano you thinking of boost or NA?
I would prefer no bigger than 77mm for boost.

std Triumph Speed Triple 1050 pistons are 79mm, I have my old manual somewhere that I will try find the rest of the specs from..

Jmac`s sketch of the modded for wedge Hicomp
would be an awesome setup very worth it as
Daihatsu pistons are super tough & quality.

Id love to find out which bike pistons go
close to 77mm as their comp heights usually
range from 25mm to 27mm allowing much longer
conrods in stroked engines.

I used ga16de pistons in my a15 ,they have 9cc of dish and 29.5mm pin height

I had my block decked 30 thou and with a 24cc head and .6mm gasket I have 11.6 to 1 comp