An Unholy Union II: Wp Extreme 50mm Conventionals on a G/S

Discussion in 'Airheads' started by Solo Lobo, Apr 9, 2011.

  1. hardwaregrrl

    hardwaregrrl ignore list

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    So, I had a little ride on some rutted, gravel roads today. First time since going back to the suspension shop. OH MY GOD! This thing in loose gravel corners like it's on rails!!!!! SOLO, be sure to add in a good bit of rebound. My rebound front and rear was way too slow, so I just kept compressing the suspension and never giving it time to reset. I'll have to let you know where I stand on my comp and rebound front and rear. I'll count them out later and post up.

    I'm still feeling pogoing from my shit tires on the street, they feel fine in the dirt. I can't imagine what I'll be able to do with this bike once I get a good set of tires on it!!! I took some video, but can't seem to download??
  2. Solo Lobo

    Solo Lobo airhead or nothing

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    Thanks for the tip Jenna,

    I have my Comp at 18 clicks in from all the way out and rebound at 14 clicks in from all the way out (way out meaning counter-clockwise)
  3. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    PLEASE PUT AN END TO THIS THREAD........you guys are making me weep:cry before I purchased my G/S I had a '93 KTM 300 EXC which was a POS and I parted it out, sold the complete front end cheap.....:cry:cry
  4. Solo Lobo

    Solo Lobo airhead or nothing

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    On the ride home, the forks still were "pogoing" a bit over almost smooth pavement.

    I wonder if I need to reduce the comp instead of increasing the restriction?
  5. hardwaregrrl

    hardwaregrrl ignore list

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    did you check your tires?:evil When you feel the pogoing, what speed are you at, were you able to peak around and watch the forks to see if there was any actual pogoing or movement at all coming from them? I still feel it, and probably will until I get a good set of tires on the thing.

    FYI from all the way out to in, I'm 16 in on comp and 10 in on rebound. it felt damn good in the gravel and seems ok on the street.
  6. Stagehand

    Stagehand Imperfectionist

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    Not wheel out of balance masquerading?
  7. Solo Lobo

    Solo Lobo airhead or nothing

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    Didn't even think of the wheel balance, DOH!

    I think I have two ounces of Dynabeads... I'll toss those in this weekend and see what happens.
  8. Stagehand

    Stagehand Imperfectionist

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    hopefully its that simple!
  9. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    Dang you guys, I'm looking at a set of forks from a 1998 98 KTM 250EXC 250 EXC. with the wheel and caliper. With the triple clamp offered here, will this be plug and play with exception of the internal springs???? Plus what size bearings will be needed. Is the front end taller than the GS front??? Plus will I need a larger rotor and adapter bracket??There has been so much going back and forth on different parts as I'm not sure what I've been reading here.


    Thanks...
  10. Solo Lobo

    Solo Lobo airhead or nothing

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    Answers for ya!

  11. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    Thanks, solo. So just adding a spacer to the damper (?) will lower the front??? I looked for your posting ton that and didn't find it, saw the pictures but no description as to what was done. How long was the pvc spacer???
  12. Solo Lobo

    Solo Lobo airhead or nothing

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    I added a 4" spacer to the damper to limit return, and once you open the forks you will see how it works.

    The rate on my 640 springs was much too light and I think the 250cc's would be even lighter
  13. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    Yeah kind of figured that. So how much do you weight??? Are you happy w/ your spring choice or is it to early to tell?

    That's great about being so easy to change the height!!!
  14. hardwaregrrl

    hardwaregrrl ignore list

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    Richard, you're welcome to ride mine at the spring fling, if that will help you with your choices.
  15. Solo Lobo

    Solo Lobo airhead or nothing

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    My custom springs are 0.54's and have 25% (IIRC) total laden sag... so far they seem very good but I haven't hit the dirt. Also I used generic oil amounts (800cc's both sides) and still have significant bandwidth I can tune (oil weight, height, shims, etc).

    I'm right at 175lbs in gear, and always, always have my panniers on with a bunch of crap in them
  16. hardwaregrrl

    hardwaregrrl ignore list

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    So I've got 800cc's of oil in each leg....10 weight. Running .65 dual rate springs, shortened from stock appx 3", I've 200mm of travel. I've lost a few pounds....I'm at 160 with gear, motocross boots included. I ran it HARD on my test track, local logging road...rutted, heavy gravel at times, packed in at times, running at about 45mph. I have never felt so planted on the bike in gravel corners....never. Remember that corner I crashed at and smashed my valve cover....I entered that at 35mph and throttled hard out of it.....the bike never waivered or left the road.:D
  17. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    Jenna- I'm hoping to make it there. It'll be good to check it out and pick your brain on it.

    Solo- you are right on my weight!!! That's gonna make things easier for me!!!

    I'd still like to do the cartridge inserts, but don't think it's gonna happen. This front end swap would be cheaper than buying the GS front end and doing cartridges, but I can sell it and recoup some of that. Should be able to break even in changing to the 50's.

    BTW- Jenna is anyone of the old schoolers going to the GA mountain Rally???? If so you guys could show me around???
  18. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    Dang girl...look out Stagehand Jenna's gonna be on your arse!!!
  19. hardwaregrrl

    hardwaregrrl ignore list

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    Hmmm....Rick from Motorrad may be there. My friend Dean Grahm usually goes, he has a pretty green R50/5, and a bunch of libertarian tattoos:D He works with Nathan. Not sure who else will be there??? I'll ask!
  20. ontic

    ontic

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    OLH,
    just to muddy the water,
    While Solo has described the good and the easy plug-and-play way to do it with Rdubb/HPMguy triples, if you don't mind a loss of some turning circle (and a small increase in trail) you could just use the KTM triples- press the stem out and get it turned to fit bmw bearings, then turn up a small spacer for the top of the headtube like so (puts the top bearing in the right place and reduces the amount- if at all- you need to to shorten the forks.
    [​IMG]
    This one is welded in but they don't actually need to be welded in.
    This is how Paul Rooney does his WP50 conversions (along with other things usually- rear end, frame, etc). He actually likes the change in geometry combined with a increase in suspension travel and feels it runs much better for cornering in the dirt.
    I am not sure what he does about the lower triple and the steering stop... (issues Solo was dealing with at the beginning of this thread).

    For the purpose of comparison to the Rdubb triples (and because I can't seem to accept easy solutions:D) I'm also working on a set of triples with an offset somewhere in the middle between the Rdubb and the stock KTM ones (YZ/WR triples sleeved down to 50mm with a 24mm offset)- an offset that combined with the axle offset of the WP50mm forks, by my reckoning actually much closer reproduces the stock G/S geometry.
    (I think it needs to be stated that regardless of whether the Rdubb triples and these forks work brilliantly or not, there is a change in geometry/trail occurring- the axle on the WP50 forks is around 13mm forward of the tube centre compared to the G/S axle- hence with the 38mm offset at the Rdubb triple the axle moves forward 13mm and the trail decreases by ...? this all starts getting very complicated with increases in suspension travel and whatnot...).

    By my testing so far, with the WR/YZ trips I shouldn't actually loose much steering lock, if any, and even with my Sauer tank I will just be scraping through (you guys with HPN tanks and the cutouts would do much better).
    If I use the stock stem (whose bearings fit the bmw races), then I'll need a spacer on the headtube like above...
    All fun and games. I need to start getting things turned for that triple. Almost ready to go.
    If I ever get the WR/YZ trips working I just want to compare them and go with the ones that feel best to me.

    After I had decided on the WR/YZ triple as the candidate (and started buying and shipping things to Solo's place:lol3) Box'a'bits popped up with a brilliant 'proof of concept' thread-
    http://www.advrider.com/forums/showthread.php?t=738023&highlight=unholy+union
    he's using the same clamps (25mm offset, IIRC there are slight changes over the years) but instead of sleeving down the triples to fit 50mm forks like I plan on, he is just running with the KYB forks. I'm not sure if I'll go the same route as he did with the stem issue or turn up a spacer for the bearing...
    we'll see.

    anyway, half way through editing this ramble, but I've gotta run. Booked in for a wrenchin session with a mate