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Product Name Unit Price Qty Subtotal
Stage Two Performance Kit - Vento/TNG
Exhaust Pipe
1 x Tecnigas Next R Expansion Pipe - Minarelli $ 140.40
Cylinder Kit
1 x Airsal T6 70cc Cylinder Kit (Min Horizontal-12mm) $ 161.10
Carburetor Body
1 x Arreche 21mm Carburetor Body - Minarelli $ 103.50
Choke Type
1 x Arreche Automatic Choke Assembly $ 31.50
Variator
1 x Malossi Multivar Variator - Vento/TNG $ 98.10
Air Filter
1 x Uni Filter Performance Airbox - Ø 38mm $ 26.10
Clutch Springs
1 x Malossi Racing Clutch Springs Ø 1.8 $ 10.80 $ 571.50 $ 571.50
Arreche Main Jet - Size 60 $ 4.00 $ 4.00
Arreche Main Jet - Size 65 $ 4.00 $ 4.00
Arreche Main Jet - Size 70 $ 4.00 $ 4.00
Arreche Main Jet - Size 75 $ 4.00 $ 4.00
Arreche Main Jet - Size 80 $ 4.00 $ 4.00
Arreche Main Jet - Size 85 $ 4.00 $ 4.00
Arreche Main Jet - Size 90 $ 4.00 $ 4.00
Arreche Main Jet - Size 95 $ 4.00 $ 4.00
Arreche Main Jet - Size 100 $ 4.00 $ 4.00
Arreche Pilot Jet - Size 15 $ 4.00 $ 4.00
Arreche Pilot Jet - Size 20 $ 4.00 $ 4.00
Arreche Pilot Jet - Size 25 $ 4.00 $ 4.00
Arreche Pilot Jet - Size 30 $ 4.00 $ 4.00
Arreche Pilot Jet - Size 35 $ 4.00 $ 4.00
Malossi Racing Clutch Spring Set $ 25.00 $ 25.00
Malossi Sport Clutch Spring Set for Original or Delta Clutch $ 22.00 $ 22.00
Grand Total $ 674.50
If I was gonna spend that much...
Polini Sport BBK - $129.24
www.sip-scootershop.com/EN/Products/P1660105/Racing+cylinder+POLINI+68cc.aspxYasuni R - $233.43
www.sip-scootershop.com/EN/Products/YA307CK/Racing+exhaust+Scooter+R+YASUNI+Minarelli+vertical+AC+with+epass.aspxHoca Variator - $49.99
www.partsforscooters.com/169-140_minarelli_90cc_variatorClutch & Contra Spring Set - $38
cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=330468303828I'd consider keeping the stock carburetor, at least to start with. If you really do want to upgrade the carb, maybe look around eBay and find a deal on a 19-21mm DellOrto. I'd also keep the stock airbox unless going with a carb that requires something bigger. Open filters are loud and they don't do that much. You could pick up Mikuni VM11/22 main jets from JetsRUs or RockyMountainATV for the stock carb.
I would also recommend a roller weight tuning kit. If you stick with a stock variator you need 15x12, with the one I posted I know you need 16x13. You can get them on eBay fairly cheap.
I know that doesn't cover a carburetor, but the Polini Sport is easier to tune and more durable for the street and the Yasuni pipes have an amazing reputation.
Another thing I would consider is this...
www.partsforscooters.com/90cc-2-stroke-1PE40QMB-EngineThe 90cc engines have a lot of potential. It's a bolt in swap. You'd still need to tune the carburetor and might need to tune the CVT. Lots of torque compared to a 50-70cc.