Hey I got honda spree. I just bought brand new 72cc polini contessa bore kit. I'm gonna put it on a sym block that never been ported, 2ab orange insert mini stroke crank, v8 pipe, ct manifold, and 28 Oko. Kelly pulley.
I weigh 220 and I was wondering what's a good set up for those parts I got. Like what kind of jets, clutch, springs, weights, etc. I just wanna get a good tune. Lmk for your ideas and help. Thanks
Polini contessa
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Wheelman-111
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Re: Polini contessa
Greetings:
The tricky part will be setting up a Contesta bore with a Ministroker. Port timing is altered considerably by the longer stroke. You have to increase the base gasket thickness for sure, possibly space the head as well (to decrease higher compression), and maybe carve on the exhaust port. If you get it wrong, that kit may make less power than a stock crank, despite the increased displacement. I also believe 28mm is too much carb for a low-revving Sport cylinder. You might find a 24 or even a 21 is faster, for sure more forgiving to tune.
The tricky part will be setting up a Contesta bore with a Ministroker. Port timing is altered considerably by the longer stroke. You have to increase the base gasket thickness for sure, possibly space the head as well (to decrease higher compression), and maybe carve on the exhaust port. If you get it wrong, that kit may make less power than a stock crank, despite the increased displacement. I also believe 28mm is too much carb for a low-revving Sport cylinder. You might find a 24 or even a 21 is faster, for sure more forgiving to tune.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Re: Polini contessa
You can run the ministroke with the Polini Contessa or Corsa as I built bikes with this set-up for here in Hawaii. Make sure you get a additional 3mm base gasket plus use the thin aluminum gasket it comes with inside the kit. Make sure you shave at least 3mm off the skirt of your piston and round the corners for piston clearance in the block. It'll bring you a compression ratio around 140-145ish but if you want more reliability use another thin paper gasket to bring the compression down to 130 range. Porting the exhaust port of the Contessa bore is also good but you gotta know what you're doing or else you can screw up the bore itself. With a V8 pipe and your weight around 220, I recommend you try 45g total roller weights first and if you don't have enough punch off the line then drop it to 42.5g. Center spring use 15%, Clutch shoe springs use 2000 rpm. 7.9 to 1 gear would be a great all-around gear ratio for you. As far as pulley , Kelli pulley and a Daytona 2 ramp is good, Jetting for the 28mm carb.... start with a 55 pilot and a 135 main jet with the air/gas mixture screw turn out 2 turns, as you may need to fine tune it later. Hope this help a bit. Good luck with your build.