Hack an Airhead GSPD, or a K75

Discussion in 'Hacks' started by rwiles, Feb 18, 2018.

  1. rwiles

    rwiles Been here awhile

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    we are possessed of an Airhead GSPD, and a K75 Low Seat Standard. Thinking of putting a hack of some sort on one or the other bike. Which one? We prefer adding a chair to the K bike, but what hack and how much is involved in mounting and setting up on the K v. The Airhead? What hack? My only real requirement is an electric lean/trim assembly. I’ve had hacks with and without the magic switch, and it’s almost a must-have.

    All advice welcome.
    #1
  2. GearHeadGrrrl

    GearHeadGrrrl Long timer

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    Either will be a great tug. The airhead is easier to do because it has more of a frame and will thus need a less complicated subframe. The K75 has a few more horses and they're watercooled, so it'll probably be capable of faster cruising. The choice may come down to where you want to ride- Dirt or pavement?
    #2
  3. rwiles

    rwiles Been here awhile

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    Pavement.
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  4. DRONE

    DRONE Dog Chauffeur

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    The GSPD's are turning into a somewhat collectible bike so I might leave that one unmolested. The K75 doesn't have an abundance of power so I'd stick with a smaller single seat car. Maybe something like a Watsonian Meteor that weighs about 150 lbs. Pic --->

    [​IMG]

    Plus, Watsonian is located in Florida so that would be pretty convenient for you.
    #4
  5. davebig

    davebig Another Angry Hun !

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    I'd leave the GSPD ,alone people are still willing to pay too much for them. The K75 is 70 hp more than the airhead but it not as torquey. A light aero sidecar will do very well on the little K, Hannigan from the Sport Series family , Sprint, Bandito or Super Sport .
    Here's a larger Hannigan on a K75
    #5
  6. richarddacat

    richarddacat I wave at RV's

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    I refer to my K bike as my K75slow. Would never think of hanging a side car on it. K100, yeah.... but thats me.
    #6
  7. ErictheBiking

    ErictheBiking Been here awhile

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    You could probably sell the K75 and buy a K100 for the same money.
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  8. Wolfgang55

    Wolfgang55 Long timer

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    If you're going to be w/ a four legged buddy, then you'd be advised to think about how it will climb in or jump out.

    But as far as the selection between your current scooters.......K75. Just don't let anyone weld to its frame.
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  9. rwiles

    rwiles Been here awhile

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    What frame? I had a Hannigan Sport on an R1100R. Bought it already built. Dunno how to rig a chair, any brand, to K bike. Someone knows how. H’ep!

    Not interested in a K100 for many reasons. A hack would be mostly for us two aging spouses to have access to a non-fall-down moto, more than anything else.

    So, basically any brand of sidecar would be worth considering. The mounting and rigging would be the first consideration. Thanx, ADVers!
    #9
  10. rwiles

    rwiles Been here awhile

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    We COULD install training wheels, I guess......
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  11. Bobmws

    Bobmws Curmudgeon At Large

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    Hi Roger,
    Check with Hannigan for mounting subframe or complete setup. Long story short, you'll spend less to purchase an assembled rig that's been properly set up. Look through the last few pages of the Fleamarket thread here in the Hacks forum.
    #11
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  12. norton(kel)

    norton(kel) vintage

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    The K75 or buy one already done as already noted. People are paying stupid money for GSPD bikes!
    #12
  13. claude

    claude Sidecar Jockey

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    From what you wrote the K75 probably would make more sense.
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  14. jaydmc

    jaydmc Long timer

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    We have mounts and sidecars for both of these bikes, next month we are making up a very small batch of leading link front ends for the K75, we also own a K75 as a shop bike that we will be running a Russian Sputnik on. As the GS is starting to be a collectors bike for the last several years every one who has asked about doing one I always recommend not to and instead buy an R1100GS to do the sidecar on because if you intend to modify the steering the airhead GS is so much more money then the R1100 that the difference in costs almost completely pays for the R1100GS which is a much better sidecar bike.
    Jay G
    DMC sidecars
    www.dmcsdiecars.com
    866-638-1793
    #14
  15. GearHeadGrrrl

    GearHeadGrrrl Long timer

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    No reason the R100GS should be so overpriced- It was one of the best selling airheads so there's plenty around. The R100GS is also one of the most problematic airheads- Great for gravel roads, but too tall and heavy for low speed manuevering, to say nothing of the mechanical problems thanks to the missing transmission circlip, paralever U-Joints, and lean jetting. The PD isn't all that special, pretty much just a bigger fuel tank that puts weight even higher and some bash plates that you can find in the aftermarket anyway... No way is the several thousand dollar price premium for a PD justified.
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  16. robtg

    robtg Long timer

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    That about covers it. :)
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  17. DRONE

    DRONE Dog Chauffeur

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    Well said, Jay! Of course, I'm completely unbiased . . . . :brow

    Deadman Point copy.jpg
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  18. Bobmws

    Bobmws Curmudgeon At Large

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    When did reason become an issue in buying/selling a motorcycle?! :hmmmmm
    As long as the current adventure style kool aid keeps flowing these bikes will bring what the market will bear.
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  19. cycleman2

    cycleman2 Long timer

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    I'm in the camp of find an existing rig that you like and fits your budget. There are so many good used, properly put together rigs out there to choose from. If not then I would go with the K75, mostly because of the water cooled. I run a R100RT rig and find that the best thing you can do for the airheads is change the rear end ratio to a 3.36, which were in all the R80's. That makes the 60 hp airhead a pretty good road bike, but you want to be content to stay in the 60-65 mph range. Yes they will go faster but they will live longer at the lower speed. I'm not sure what rear drives where available with the early K bikes, but somebody else more familiar will eventually come along.
    #19
  20. davebig

    davebig Another Angry Hun !

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    cycleman2 post us some Canadian listing !
    #20