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  1. #1
    Buzzer68's Avatar
    Join Date
    Oct 2006
    Northern Illinois

    1200 SS to 1390 SS

    I'm planning to turn my GP1200R Superstock into a 1390 SS. From the topspeed database, I see there are some 1390 tripple piped GPRs out there that are pretty fast. What, specifically, are you guys doing to the engine and pumps besides the GroupK 1390 bore sizes and porting? My SS is a 2001 Riva custom (light hull). So, the fucus is on the engine and pump for starters, ie port timing, compression ratio, carb specs, fuel pressure, msd total loss programming, facty pipe tuning, fuel type, fuel/oil ratio, Its has a 158mm 12 Vein custom setback, R&D transomplate modified Pro shoe and single bar. Its a 16/20 impeller recently repaired to tighten up clearance, custom 87/92 Riva mm nozzle matched to 158mm stator,
    Thank you in advance for the input

  2. #2

    Join Date
    Jan 2007
    Milwaukee, Wisconsin, United States
    dude buy my FZ

  3. #3

    Join Date
    Apr 2006
    panama city beach 'fl
    lets see ,if it were my setup woodys or tj porting, late model non power valve pipe(tripes are pain) novi or black jacks 46mm ,advent ,stock 85 mm nozzle,prop swirl 15.5 /24 with .050 setback to start, v force 3 reeds,case porting,36-1 mix kloz
    OR sho motor

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