2002 KTM Adv. 640 suspension

Discussion in 'Thumpers' started by afgarcia2, Jan 8, 2004.

  1. afgarcia2

    afgarcia2 woofkeeper

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    I would like to make the suspension on my 2002 640 adventure so the bike is can handle more agressive riding off road . I am actually contemplating using the 640 for desert racing.

    Has anyone modified their 640 Adv. suspension in this way, or does anyone know of an outfit in the US that I can trust to modify my suspension for moe agrerssive riding? I have had bad experiences with suspension modifications that resulted in an unbalanced bike, so I would really like to know of a company that has settings established that will make for a balanced, stiffer ride.
    Thanks in advance,
    Tony
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  2. Cat0020

    Cat0020 El cheapo

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    The suspensions of a LC4 Adventure has good amount of adjustment to them. You might be able to experiement yourself before sending the forklegs and the rear shock out for re-valve or tuning work.
    By more agressive off-road riding, do you mean more rocky terrain with multiple stage bumps or to handle big hits in the desert?
    Where are you located?
    How much do you weigh?
    What kind of terrain do you ride in?
    You can always raise the forklegs to make the bike handle more agressively..but I doubt you want that for desert riding.
    #2
  3. afgarcia2

    afgarcia2 woofkeeper

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    Thanks Cat0020 for the excellent and speedy reply. I had no idea about the adjustability of the 640 suspension because have been hesistant to make any adjustments. The bike as delivered is soft but very well balanced, and I did not want to screw up the balance.

    I weigh 155 lbs without gear.

    By more agressive off-road riding I mean able to handle stage bumps, whoops, and especially big hits. I am willling to exchange harshness on rocks for peace of mind about big hits. I haven't raced in about 10 years, but I have the itch bad, and I want to participate in the Vegas to Reno this year. I recognize this will be a huge challenge, but i know how to train, and I think the 640 can do it if it is set up properly.


    I usually ride in the central Coast Ranges of California, a place called Pozo, and another called Clear Creek (where the Quicksilver National Enduro is held). At present, I have cased and bottomed the 640 pretty hard on medium sized whoops and "g-outs" at Clear Creek. Clear Creek is my favorite place to ride. there is almost everything there: from whooped out trails to tight and technical, rocky trails, to steep climbs and descents. Again, I would not mind harsheness in the rocks there, if it means capability to handle whoops and large hits.

    I would be greatful for additional feedback on this Cat0020.
    THANKS!
    Tony
    #3
  4. Rad

    Rad Done riding

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    The WP suspension adjustments will keep ya busy for a long time

    First thing, set yur sag, then copy the pages from the WP manual and take them with you to Clear Creek. Pick a section ya like, include the big whoop if ya want. Start out with the recommended settings then keep run'n the same section make'n small adjustments, one only at a time until ya like it.

    I think at 155lbs you will have no problem make'n that suspension work for you, it just might be the best suspension in a stock bike made today.
    #4
  5. Cat0020

    Cat0020 El cheapo

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    At 155 lb. the suspension adjustment should be able to take care of your needs.. unless you are trying to ride the LC4 like a motorcross bike... then stiffen the suspension might just taco your wheels, because it weights so much more than a motorcross bike.

    For big hits, slow your rebound damping and up the pre-load. Do small increaments of the damping adjustment first. Rear shock spring pre-load can easily get too much and bounce you off after you land a big hit.
    LC4 is not a motorcross bike, ride smooth.. I had to keep reminding myself of that, too..
    :1drink
    #5
  6. Mack

    Mack Gone, but never forgotten. RIP, Mack...

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    A real good read on riding a tourbus fast, would be Dirt Bike magazines December issue covering the prep of a 626 SXC, and it's entry into the 24 hours of Glen Helen.
    #6
  7. afgarcia2

    afgarcia2 woofkeeper

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    Thanks to all of you for your help and advice. I have ordered a back issue of the December 2003 Dirt Bike, and I will heed the ride smooth advice. I am very busy with work until March, so it won't be any time soon, but I will proceed with testing following the advice given by Rad and Cat0020.

    THANKS!
    Tony
    #7
  8. inte

    inte neophyte serendipity

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    For what it's worth...

    I recently purchased a "used" 640 Adv - sold as new with just over 1000 miles on it. Larry Roseler owned the bike & his shop used it for a demo bike and Larry did some photo ops on it for Dirt Bike Magazine (I think the pics will be in the Feb or Mar issue).

    When I bought it, there were a few modifications done to it - one of which was the suspension - a heavier shock spring and heavier springs in the fork tubes were installed, and all the suspension was re-valved to compensate. I didn't order the work, so I don't have the specifics on what components were installed. I have very limited experience on stock 640 Adv's but they feel very soft by comparison - I'm 180 lbs.

    Precision Concepts (Bob Bell Suspension) did all the work on the suspension - I think they're located in Hesperia, CA.

    Here's the bike the day I picked it up:
    #8
  9. Drif10

    Drif10 Accredited Jackass

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    inte,

    how did you make out with your IMO?
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  10. inte

    inte neophyte serendipity

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    forgive my shallow knowledge of intenet-speak, but what is an IMO?
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  11. afgarcia2

    afgarcia2 woofkeeper

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    Thanks <inte> - I am going to contact Precision Concepts. At the risk of discrediting folks above who gave generous advice, my hunch is that I need stiffer springs. The ADV. 640 mnual says that the bike comes with the sag set for a "165 lb. rider" I never checked it, but the bike feels right and balanced, just too soft for my intended use.

    From what I was taught, if the springs are too soft, increasing the preload can reduce the sag below what it should be, and may not solve the problem. Does that sound correct?

    I will call the folks at Precision Concepts.

    Many Thanks,
    Tony
    #11
  12. Drif10

    Drif10 Accredited Jackass

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    Not internet-speak. KTM-speak.

    It's what they call the LCD odo/speedo/trip meter.

    Your dash, man, your dash!
    #12
  13. Drif10

    Drif10 Accredited Jackass

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    Not so fast, bub.

    The Adv does not have preload adjusters for the front, stock.

    But you can buy them from the KTM Hardparts catalogue. $200? I think.

    I'm 6'3", 215 lbs. Bad knees so I make the bike do more of the work, it needs to be stiff. Worked fine for me, without having to go big on it.

    Flanny had his forks rebuilt, and seemed happy with the results.
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  14. inte

    inte neophyte serendipity

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    so you've seen my other posts!

    still waiting on that. I actually went out & met with Larry (Roseler) a couple weeks before he left for the Dakar. He came to the same conclusion as me - the computer itself is fritzd. I was told a new one would be ordered - haven't heard anything since.

    For now I'm doing long rides without adding any miles to the bike :evil

    Just did a 362-mile loop from my place in Orange County, down to the Mexican border, then over to the southern terminus of the Pacific Crest trail & followed that until a myriad of gates forced a paved go-around...
    #14
  15. afgarcia2

    afgarcia2 woofkeeper

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    hey drif10 - thanks very much for the heads up, and sorry to be a pest, but can you please clarify your response? Do you mean that you added the for preload adjusters (I saw them in the catalogue too), you were able to make the forks stiff eneough for your needs? If you found success, I think I will try your an the above proposed soutions first; I always like simple solutionsmopre than complex ones, and if the revavle does not work for me, then I woudl really be lost!
    THANKS!
    Tony
    #15
  16. Rad

    Rad Done riding

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    Ya gotta set a bike up for what you want not someone else.

    I love ride'n fast desert. The rule there is ya hit 1,000 little bumps for every big one. Ya set the suspension so you can run fast and slow for the big ones.

    Set the suspension for what ya want. The only thing I will say is ya really need to set the sag yurself and find out if it really is too soft instead of guess'n
    #16
  17. Mack

    Mack Gone, but never forgotten. RIP, Mack...

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    Afgarcia2, Just remember the bike has 12" of travel, so yes the spring rate is soft, but it makes up for it in total travel. I have had thoughts of going stiffer, front and rear as well, I'm over 230 in gear, and I'm generally packing too much crap. So far the bike has taken some pretty hard hits, and soaked them up, until it shows it's lacking I'll stick with OEM. Let us know what you figure out.

    Don't expect too much from the Dirt Bike article, it's good but topical. But they do list all the mods and why they did them, and mention the weight issue, and how it effects the way the bike needs to be ridden.
    #17
  18. Flanny

    Flanny Flanny-it-up!

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    I weight 175-185 with a pack & gear on plus about 10lbs of tools and crap on the bike usually.

    I had the following done on my bike.

    Forks
    - Stiffer fork springs in the front, -
    - MX-tech suspension valves in the fork
    - Proper oil weight in fork
    - proper oil level in fork
    - new fork seals

    Rear Shock:
    - MX tech valve
    - Rebuild seals (while I was at it)
    - Stock spring

    I like to ride fast/rough/rocky fire roads and I think I ride fairly agressively, although I would never take the adventure on a mX track or anything crazy like that.

    The biggest complaint I had that lead me to suspension mods were:
    1 - the fork compression stroke was pretty harsh landing from a wheelie drop on big dips in the road/track (like a 50 kph dip where you can loft the front wheel and catch a bit of air with the back). No matter what I tried in adjustment, I could not make it go away. It was a sort of brief harness that runs into your wrists a little...
    2 - the bike tended to "wallow" in fast seated and standing slide around corners at higher speeds (like 60-80kph)...not alot, but noticeable.
    3 - If I dialled the bike stiff to avoid bottoming, and stop the wallowing, it would be a little harsher, and would tend to slide out a little more easilly, and be harder to hook-up. I could not find a good balance.

    I sent my fork and shock to Jim Hunt at Cycle Improvements after spending about an hour with him on the phone answering all kinds of question he had about what I rode on, what tires I use, how fast I go etc, etc, etc.

    I got the fork and shock back in a week! WOW Service!!!

    Anyway, you all can say what you want about how good the stock suspension is (and it is compared to other machines), but the re-valved, and re-sprung bike is incredible. Nigt and day difference. Believe it or not, I noticed the difference from the moment I left the driveway on the paved road!!!
    - The bike's straigh line stability was tremendously improved (like in a cross wind for example). It just seemed much better planted.
    - small irreguliarities on the trail REALLY, REALLY just dissappeared (whereas I'm sure I would feel them before)
    - The "harshness" on drop-ins was gone
    - The bike powerslides very smooth, perfect arches around corners --all wallowing is gone.
    - Extra unexpected bonuses...Better traction & hook-up, high speed cornereing on the pavedment is noticeably better (again less wallowing).


    Bottom line - PLUSH, PLUSH, PLUSH! It is now sort of like...hmmm...like I don't really worry about the line I need to take so much anymore, 'cause the suspension is a non-issue....it's that good.

    I was very skeptical that I was taking a big gamble on what everyone says is "such excellent stock suspension", but after spending 700 bucks, I would say that aside from the TM40 carb, this was the single best thing you could do to the bike. I'm so convinced, that I'm pretty sure the first mod I make to any future bike will be to send my suspension to Jim again.

    So...GO FOR IT..you won't be sorry!!! Just be sure to get it done by someone who knows what they are doing, and are willing to spend the time to understand your needs.

    If you want, I can transcribe all the specs from my "personl spec. sticker" that Jim taped to my fork tube.

    Anyone over 200lbs would benefit FOR SURE. I was borderline on Jim recommending a stiffer rear spring for me, so for you bigger guys, I'm sure you're making your compression knobs work harder than they need to...

    Just IMHO....

    Cheers folks!
    #18
  19. Mack

    Mack Gone, but never forgotten. RIP, Mack...

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    Good info, thanks Flanny, guess I'd better loose some weight or start saving. :):

    PS. Hope Charlie's doing ok. Man I feel for the guys on these last few stages.
    #19
  20. Flanny

    Flanny Flanny-it-up!

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    Yeah...I've been watching them both (Arredondo and Roseau) at every checkpoint as soon as I get up. The last two days look like they were awful, and today is huge as well...

    Both Charlie and Franscisco are listed as not having started this rmorning...looks like their Dakar is over...

    Bummer...

    But man...inspirationsal...those guys (Charlie especially) were fdoign so well before stage 7...
    #20