DRZ Forks and HPN Tank on a R100 GS PD

Discussion in 'Airheads' started by Daithi, Jan 2, 2012.

  1. Ras Thurlo

    Ras Thurlo Desert Lion

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    The HPN tank allows you to have petrol far lower down and further forward than the stock tanks - which IMHO really helps handling off road, the key is to be disciplined in limiting the amount of fuel you fill it with.

    I would rather have 19l in the HPN than the stock G/S for the above reason.

    I really feel this benefit when going very slowly over technical ground, as you can almost balance it like a bicycle courier at traffic lights.
    #81
  2. Prutser

    Prutser Long timer

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    Phil,

    Keeping a low seat height and gaining more travel is tricky.
    If you would like to do so you might end up with travel that can not be used, because the sump and center stand will be touching the ground.
    I totally see that creating the longer wheel base would give more room to keep the weight off the luggage between the wheels and not behind the rear axle.(specially with 2 up)

    On the Sibirsky trip I started with the luggage right above the rear axle. At the end of the trip it was all moved forwards.
    Until it was almost touching my heels. With every cm I moved it forward (and down) the handling improved A LOT !!!!

    Cheers
    #82
  3. buls4evr

    buls4evr No Marks....

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    I see a thread like this and always wonder why someone who would go to all the effort to change their forks would pick a 20 yr. old design for a replacement. May I suggest to anyone else doing this that USD MX forks are plentiful on the used market and already come with very stiff springs for MX jumps. They can be altered internally for length or travel ala flattrackers. Why not use those? DRZ forks are notorious for their many "needs".
    #83
  4. Stagehand

    Stagehand Imperfectionist

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    USD's are not without their troubles. Stiction, and lack of steering radius. WP 4860's are already 15 years old technology. There are lots of good forks out there. DRZ's are Cheap and very decent. And an easy swap, compared to some, so you calculatethe plusses and minuses.
    #84
  5. Prutser

    Prutser Long timer

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    Because the 20 year old design still works fine and has less friction than most modern USD forks.
    The top of the fork is thinner than an usd so you could keep more steering angle before you hit the fuel tank.
    They can be altered internally for length or travel too, just like the MX USD forks.
    BECAUSE A LOT OF PEOPLE THINK THEY ARE WORSE THAN THE USD THEY ARE CHEAP :thumb
    #85
  6. Ras Thurlo

    Ras Thurlo Desert Lion

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    ....and maintain the traditional look that some of us love
    #86
  7. hardwaregrrl

    hardwaregrrl ignore list

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    USD's are also notorious for blowing forks seals way more often than conventionals. If you really look around at people using their DS bike for true off road traveling, the forks are the first to go. Either they go after market, or backwards. Manufactures are noticing the starbucks adventure bike trend and cutting corners in the suspension department, so the 20 year old design is actually better than some of the forks on modern DS bikes.
    #87
  8. Daithi

    Daithi Destination Unknown.

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    For all the reasons above and because all the parts I needed were available and very cheap/free.


    After going to the trouble of offsetting the 18" rim 25mm it looks like I'll need a spacer to keep the disk away from the boot. I have a choice of three disks, 1100GS, K100 or 1100R......
    #88
  9. Rucksta

    Rucksta SS Blowhard

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    Plus the rear end is still the weak spot with suspension performance (para or mono) and there is only so much to be gained upgrading the front end until the rear is addressed - even then there is only so much you can do with the rear.
    #89
  10. buls4evr

    buls4evr No Marks....

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    OK if you just want a "look" I can see it..... but no way is that DRZ fork as good as a nitrided USD fork in any way... strength, stiction, triple clamp rigidity are all way better on the USD. The DRZ forks are just CHEAP and are a really old design. As far as the rear shock goes, you get what you pay for . An Ohlins would be a drastic improvement.
    #90
  11. Daithi

    Daithi Destination Unknown.

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    Just got the call from Hagon, rear wheel is on it's way and should be with me tomorrow afternoon. :clap



    I think the two previous posters have missed the point completely by the way.
    #91
  12. Prutser

    Prutser Long timer

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    Can't wait to see how it looks :evil.
    #92
  13. Dmaster

    Dmaster Been here awhile

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    USD = Stiction,... or at least all USD forks I saw had a stiction problem. :cry
    Even with fancy SKF seals.
    Old designs won't have to be bad, and the cartridge damping system is really useful in this fork. (if reshimmed by someone who knows what he is doing, it will be GOOD) but stock Suzuki its not bad at all.
    And after all the USD fork is an old desigen to..
    [​IMG]
    Ok that's not really "fair"
    But see this '85 KTM :puke1
    [​IMG]
    And, a USD is more "stiff"
    This will be more stressful for the frame. Actually, i bend my frame with a USD fork in it (the fork is still straight... )

    I even heard story's of old factory Suzuki's RM-Z? going to USD forks, but they changed it back to ride side up because they where better. Then there sale numbers dropped so they changed back to USD.....
    Costumer didn't want it because of the "old" design.

    A good rear shock isn't a problem imo, its the HEAVY final drive that bothers me.... :(
    Who can make one under 5KG? :evil
    #93
  14. Stagehand

    Stagehand Imperfectionist

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    I Literally have one of those hanging in my barn :D
    #94
  15. Dmaster

    Dmaster Been here awhile

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    -1 :sick

    :evil
    #95
  16. Stagehand

    Stagehand Imperfectionist

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    :rofl
    #96
  17. Daithi

    Daithi Destination Unknown.

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    I'm nearly good to go, one thing is bothering me, do I need a rimlock given the weight, torque of the bike and the tyre type (S12) would a rimlock be a good or bad idea ????? :ear:ear
    #97
  18. Prutser

    Prutser Long timer

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    All depends on the tire pressure!!!
    On my bike I tried several brands and types of rimlocks.Most of them are not strong enough for the Boxer :D
    When there is 1.8 bar in the tire its ok. But I like to use 1.6 or even 1.2 bar.Depending on the terrain and tire....
    The ones from Motion pro are ok.But not good enough.
    I'm just about to fit one like this from Talon.
    [​IMG]
    #98
  19. Daithi

    Daithi Destination Unknown.

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    That looks the job, I'll use what I have because I'm getting impatient but I'll order one of those and fit it after the next tyre change.


    Well the wheel arrived de-chromed and powdercoated and looks great.
    [​IMG]
    I need to extend the linkage to the master cylinder and weld a tab to the old drum brake lever, I want the master cylinder tucked out of the way so I'll mount it inside the subframe with a 6" pushrod.




    I needed to shim the wheel so the brake disk wouldn't rub the FD boot which meant the wheels bolts were too short so I turned a new set of shorter cones for the wheel bolts (right of pic below). Also the calliper was rubbing off the spokes but the shim sorted that.
    [​IMG]

    [​IMG]

    One thing I read in Phil's thread was the calliper needed to be unbolted for the wheel to come out, for some reason I don't need too remove the calliper ???


    This is the space I have for the 120/90/18
    [​IMG]
    I'll take a lump hammer to the exhaust box if necessary.:evil


    Here you can see the 1mm gap between the FD boot and the rear disk after the 3mm shim was fitted.
    [​IMG]

    Offsetting the wheel means the torque arm needs needs to be offset too, I'll mill 3mm off it then put in a 3mm washer.
    [​IMG]

    One good thing is the disk from the r1100r is the same as the GS one and I have one spare.
    [​IMG]
    I'll have the tyre fitted tomorrow !

    [​IMG]


    DRZ1000GS
    #99
  20. Daithi

    Daithi Destination Unknown.

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    Decided to go with a rim locked MICHELIN S12 XC for the back, with 6mm thick heavy duty tube.
    [​IMG]
    I'm wondering if I might not get a 140 in there. [​IMG]