Gen 1 diff on a Gen 2 swingarm

Discussion in 'User Mods' started by jedi-, Oct 7, 2017.

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  1. Oct 7, 2017 #1

    jedi-

    jedi-

    jedi-

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    A project that is almost complete. A bit off messing around but it's sorted out now and really not that difficult having sorted out all the measurements now.Need to just screwcut the thread on the high tensile axle.
    The diff shown is only an old unit and won't be the diff used .
    We just need to finish up the drive splines which I will update shortly as I machine it.
     

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  2. Oct 7, 2017 #2

    Damon

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    Nice work, keep us posted!
     
  3. Oct 7, 2017 #3

    Fire-medic

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    I assume the install is for a Gen 1? How much difference is there in swingarm pivot width, and pivot pin diameter?
     
  4. Oct 7, 2017 #4

    jedi-

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    For Gen 2
     
  5. Oct 7, 2017 #5

    mabdcmb@yahoo.com

    mabdcmb@yahoo.com

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    Nice work as usual but I gotta ask, why?

    Sent from my SM-G930V using Tapatalk
     
  6. Oct 7, 2017 #6

    rzwanink

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    Not only u are wondering.... WHY
     
  7. Oct 7, 2017 #7

    Fire-medic

    Fire-medic

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    I can see it being fitted to a Gen. 1 but why would you want that on a Gen. 2? Sounds like putting a 7.9" rear end and a cast-iron Mexican 4 speed behind a hot Fox-body 302 Mustang GT like Ford did, before wising-up, and going to a Borg Warner T 10 5 speed, and an 8.8" posi rear end.
     
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  8. Oct 7, 2017 #8

    adambweird

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    Only thing i can think of is, it might have a numerically higher final drive than the gen2 does... if so, this would be the easiest way to help a heavier bike hustle down the track faster. Like switching to 3.73 gearing from 2.41.
     
  9. Oct 7, 2017 #9

    jedi-

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    Why? I can't really go into much detail as it's not mine to discuss but other than to say it changes the ratio obviously
    It may blow itself to bits? But on the other hand it might be a solution...

    I'm sure we will know for sure in due course :moped:
     
  10. Oct 7, 2017 #10

    Fire-medic

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    well if it lowers the final drive numerically, it could be for a top end record run.
     
  11. Oct 7, 2017 #11

    adambweird

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    Very true, wasnt thinking of that. I think though the gen
    1 is higher than the gen2. Gen1 is 3.66 or 3.67 if i remember correctly and i think the gen2 is a little bit over 3.
     
  12. Oct 7, 2017 #12

    Traumahawk

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    If thats correct, it will allow the gen 2 to get out of the hole quicker.....if it will stick.

    Thats like going from 3.23's to almost 4.11's.
     
  13. Oct 7, 2017 #13

    Fire-medic

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    Better buy the Gen 1 pumpkins by the 6-pack. They aren't designed for 200 RWHP a modded Gen 2 can provide.
     
  14. Oct 7, 2017 #14

    1FK00

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    I wouldn't want to be on a bike at any speed with a disintegrating ring and pinion.
     
  15. Oct 7, 2017 #15

    adambweird

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    Cryogenically harden the gears to help em out like they do with the driveshafts, put the widest slick possible on, add some wheelie bars and let the carnage begin! If it holds together and has grip, should FLY outta the hole!
     
  16. Oct 8, 2017 #16

    one2dmax

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    We asked Steve to take on this project and sent him all the parts. The goal was to have another gearing option for the gen 2 Battlestar bike and of course anyone else with a gen 2 that wants an option.

    The stock Gen 2 rear diff is a 3.22 Ratio rear end.
    With this conversion we can run either a Venture/Royal Star diff which has a 3.33 ratio OR
    A Vmax rear diff which has a 3.66 ratio.

    We're going to give up top speed for acceleration.

    I did make two conversion kits to install a gen 2 rear swingarm to the gen 1 vmax (and have enough parts to make one more but it's not a cheap kit). This setup would also be able to be used if so desired. I didn't ask Steve to make it possible to fit a gen 1 wheel but I imagine that could be done (though not sure why you'd bother).

    As far as durability. They hold up to 170/180 rwhp bikes and gen 1 rear diff failures are pretty rare to have complete failure anyway. I don't think i'll be launching it off the two step but rather launching it with the normal hand slide release. On the street in short runs the 3.66 gear will be awesome for acceleration! And it's a LOT lighter rear diff so more HP makes it to the ground and less mass to move along.
     
  17. Oct 8, 2017 #17

    Fire-medic

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    Well Sean is the authority on the Gen 1 mods, so if he says it's good-enough for a stock bike Gen 2, there it is.
     
  18. Oct 9, 2017 #18

    rebeltaz83

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    As far as durability. They hold up to 170/180 rwhp bikes and gen 1 rear diff failures are pretty rare to have complete failure anyway. I don't think i'll be launching it off the two step but rather launching it with the normal hand slide release. On the street in short runs the 3.66 gear will be awesome for acceleration! And it's a LOT lighter rear diff so more HP makes it to the ground and less mass to move along.[/QUOTE]

    The hp numbers are close, but I'm more leaning towards the torque output, that will do the diff. In. And the added weight of the gen 2 compared to a gen 1?? I snapped a shaft on a stock gen 1, so would the shaft be the weak point, not the diff??
     
  19. Oct 9, 2017 #19

    Fire-medic

    Fire-medic

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    That's correct from my mechanic friend who's built power adder VMaxes.

    The hp numbers are close, but I'm more leaning towards the torque output, that will do the diff. In. And the added weight of the gen 2 compared to a gen 1?? I snapped a shaft on a stock gen 1, so would the shaft be the weak point, not the diff??[/QUOTE]
     
  20. Oct 9, 2017 #20

    Itgoes

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    Piped and tuned Gen 2's are 190 - 210 HP and 135 lbs + TQ.

    I appreciate the effort going into this but I don't think the Gen 1 rear stands a chance on a built Gen 2......especially at the track where it will hook.

    Might get away with it on the street if not abusing it.
     

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