KX100 what in the world to do?

Discussion in 'Thumpers' started by ggamster, Mar 5, 2012.

  1. troy safari carpente

    troy safari carpente Team f5ool

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    While the cubic capacity overlords (they're the ones that tell us all that we need a 900 to 1200 cc multi cylinder motorcycle if you're into "adventure riding" :wink:... and that if you venture into the "woods" on anything less than 450cc enduro-cross superthumper - you're gonna get stuck on a hill somewhere :evil) may cry out at your lil' Kawa' 100cc project... :norton

    Maybe the "patron saint" of this thread should be...:deal

    [​IMG]

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    1989 ISDE Germany... Gold Medal... :deal
    [​IMG]


    [​IMG]

    Or what about this later version; KX 80 motor in a perimeter framed KX 125 chassis... Multiple ISDE Champion Gian Marco Rossi rode a bike similar to this one in the 1990/91 & '92 world championship enduro seasons...
    [​IMG]

    I saw him (close up and personal) ride the wheels off one at the 1992 ISDE in Cessnock Australia... and there was HEAPS of dusty rutted, rocky gnarly single track at that event, not to mention STEEP technical hills with rock steps and ledges...

    Sure, if you're on the portly size of things or just "joe average" who wants to mozy on around the trails... a 350 to 450cc fourstroke is probably going to be the choice...

    But I've noticed of late a big swing back in popularity of sub 250cc bikes (especially 200/125cc two strokes) in the nitt gritty single track enduro scene. Remember when everyone went gaga the year Shane Watts overalled severall GNCC races on a 125... :1drink

    For a trim rider (say sub 65-70 kgs), who is not timid with the shifter and handy with the throttle... a sub 125cc bike will do the job more than well... :clap

    For the good ol' "overlords", let them have their tried and true "big bores" :wink:

    Good luck with gettin' the screamer sorted... :thumb
    #21
  2. Switchblade315

    Switchblade315 Long timer

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    Look into the pit bike world. you'll find a lot of good things there for what you are doing.
    #22
  3. ggamster

    ggamster Been here awhile

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    Troy, thanks for all the info. That is a cool article. I appreciate your time in posting the cool old pics. I rode the bike this evening and it was great. I will have some peg and bar issues and flywheel, but I'm in control the hole time, I can put that bike where I want it and it feels like I can giver hell. (got wait to break it in.) Speaking of break in, I would normally do a few slow rides and let the bike get up to temp then cool down. I would do this a few times to help primarily with gear mesh, but I noticed Kawasaki recommends taking the top end off, removing any scuffing and replacing the rings. Is that necessary. Seam like a bit of overkill but no big deal if I truly should.
    #23
  4. welder

    welder Long timer

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    I don't get it . why not just buy a trials bike?
    #24
  5. troy safari carpente

    troy safari carpente Team f5ool

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    http://www.youtube.com/watch?v=Zfcrm6PbWj4

    These things are current euro 50cc enduro bikes...

    ... though at this point in time (for some balance/perspective to the discussion), it is probably prudent to say that none of these blokes are 6ft 1" and all are a fair bit under 190lbs. :brow As you can see from the earlier posted photo's; LR was of a pretty trim/jockey like stature, back when he rode the 80cc Kawa' in the ISDE... and Gian Marco Rossi was maybe 170 lbs all up, with his riding gear on, and a brick in his bumbag...


    so... just syain'
    #25
  6. pookiebear

    pookiebear Long timer

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    pitbike tall bars.
    EFM auto clutch (optional)
    11oz flywheel weight.
    bigger rear sprocket
    bark busters.
    Taller cables from motion pro, just call them and they will make them. (if you need em)
    Longer stainless brake line up front.
    Ebay wide pegs.
    Coolant overflow bottle. (cant remember if it already has one) if you find it boils in the woods.
    You already got the springs for your weight coming. I would not mess with the oil until you have tried the springs first.
    tall seat if your legs get cramped.

    my qualifications for such recommendations?.... I am 225 lbs and used to ride a kx65 as a pitbike with just springs and a tall seat and bar risers. The naysayers around here can pound sand, jerks.

    One of the things I have seen is to swap the 19/16 tires to 17/14 and it makes it more pitbike-ish in the ride which lends itself to woods very well.
    #26
  7. ggamster

    ggamster Been here awhile

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    Cool thanks, I have a 54T rear sprocket (3 up), a 10oz FWW, 1 1/8" Protaper conversion kit, wider grips, heavy duty clutch springs, skid plate, .5" rear set wide foot pegs, frame protectors, O-Ring chain, Pro Circuit Nature Friendly Silencer, barkbusters, and springs on order. I hope to have them in soon.
    #27
  8. sixstringsteve

    sixstringsteve Adventurer

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    I totally understand your reasons, I think it's a great project.

    I'm 5'6" (28" inseam) and I'm not an expert rider by any means. i enjoy very tight singletrack with switchbacks, steep climbs, rocky trails here in Utah. I'm a 2T guy, and I love the feel of a full-size bike until I dump it on a steep, technical climb. Then I can barely pick it up, and I have a tough time getting my leg over the seat to start it. I realize you don't have any of these problems, but I just wanted to say I totally understand the desire for a little lightweight, flickable bike. If the kx100 had another 4" of wheelbase it'd be the perfect bike for me. Subscribed, and looking forward to your outcome and hearing your results.
    #28
  9. ggamster

    ggamster Been here awhile

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    This could be a bit to much info for most, but I thought it was crazy how detailed it was.:eek1

    http://3cyl.com/mraxl/manuals/chamberdesign/2003exhaust.pdf

    The reason I was reading is I was debating about using exhaust wrap on the upper part of the pipe where it gets close to the tank and carb. I'm still not sure if I'm going to do it, but I was wanting to reduce some noise and keep the fuel as cool as possible. I understand that the scavenging effect of the pipe works off of sound waves and that wrapping the pipe could effect that. This is the reason for the partial wrap, but if there is a down side other than potential rust I won't do it. I have read very mixed opinions on this and don't have my mind made up. Done anyone have results relating to this?
    #29
  10. ggamster

    ggamster Been here awhile

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    Thanks, I do have the hillside pickup problem and it sucks. I have a ton of short super steep rocky climbs and if you don't make it on a full size bike it is all most impossible to get the bike stood up and ride up. You have to drag the bike until the body is above the wheels and stand it up. Screw that. Give me light and fun.
    #30
  11. Tbone

    Tbone off-ramp slayer

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    On 2 strokes I don't think heat will be an issue. I'd skip the wrap.
    #31
  12. ggamster

    ggamster Been here awhile

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    Here is the answer to the above question. I guess I won't be doing the wrap.

    "Another approach to altering the tuned RPM of an expansion chamber is to alter the speed of the pressure waves inside the exhaust pipe. The speed at which pressure waves travel is greatly affected by temperature: higher temperature means faster wave speed. As a result, expansion chambers can be retuned for higher-than-design RPM resonance, by increasing the average temperature of the exhaust gases inside the pipe. Techniques to achieve this increase in gas temperature can include: insulating the pipe (thermal wrap), restricting flow from the pipe (smaller stinger diameter), or by retarding the ignition timing at the correct RPM (a later burn allows more heat to escape into the pipe).
    Conversely, a pipe can be retuned to work at a lower-than-design RPM range by reducing the temperature of the exhaust gases. Injecting water or a water-alcohol mix into the headpipe of an expansion chamber can reduce temperatures significantly, enough to lower the tuned RPM of an exhaust system by as much as 1500-2000 RPM. The heat absorbed as the liquid changes into a gas is responsible for the drop in temperature. As a result, the two stroke exhaust can be tuned to stay "on the pipe" over a remarkably wide RPM range, if the designer takes advantage of all the tools available."



    this is straight from Wikipedia if you can believe that.
    #32
  13. Kawidad

    Kawidad Long timer

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    I like what you're doing. We need more pix......:wave

    :lurk
    #33
  14. mts49

    mts49 Adventurer

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    Cool project, keep us up on it!

    Moar pictures!!
    #34
  15. ggamster

    ggamster Been here awhile

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    Ok, so I got the bars, grips, risers/adapters, and the 10oz fly wheel weight in today. I will be posting photos this weekend of the install and the differences.
    #35
  16. dentvet

    dentvet Long timer

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    Good.

    I found helmet cam footage of mine. Its pretty mundane but it does point out some of the things you might encounter. There is a loose rocky hillclimb that I fail on due to deflection and then poor throttle control/lack of traction. Its a moderate hill that is pretty doable (75%) on full size bikes. I would have done better in a gear or two higher, more corner momentum ,clutch feathering etc.

    [​IMG]
    #36
  17. ggamster

    ggamster Been here awhile

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    So like I said. I got the bars, riser/adapters, and grips yesterday afternoon. Last night I put them on and documented the changes as much as possible. Some of my info maybe a little simple for most to figure out, but I like detail. So here you go.

    The parts are:

    The Bars are Pro Taper Henley Bend (one of the tallest with least bend bike I could find. I wanted to open up the cockpit as much as possible.)
    The adapters are Pro Taper
    The Grips are Scotts
    [​IMG]

    The tools needed are:

    Razor Knife
    Drimmel Tool
    10 mm socket
    8 mm socket
    6 mm allen
    Ratchet
    philips
    Blue Threadlock
    Type 2 Gasket Sealer

    This should be what it look like when you start.
    [​IMG]


    First cut the grip off of the throttle tube. Be sure to remove all of the old grip material.
    [​IMG]

    Now that you have the grip off loose the two philips screws under the rubber guard.
    [​IMG]

    Now using your philips and 8mm socket to remove everything from the stock bars.
    Next use you 10mm and remove the four 10mm hex head bolts holding the bar clamps on.
    Remove the bars.
    You can see the difference in the bends.
    [​IMG]

    Ok, so now you have the bars off and it is time to install the adapter/risers. Put a little blue thread locker on the four black 6mm allen head bolts.
    Bolt the adapter/risers on with the overhang facing outward.
    Tighten them down into the factory bolt holes
    It should look like this when done
    [​IMG]

    Next be sure to spread a little of the red grease that is stuck down in the throttle when the factory put to much in.
    At this point you may want to use your dremmel tool to remove the end of the throttle tube if you are doing BarkBusters latter.(Which I am)
    Then slide the tube assembly over the loose bar.
    Next set the bar in the new mounts
    Apply thread locker to the four 10mm bolts supplied and install the top caps lightly
    I make these tight. I don't worry much about factory torque specs on bars. Make them so they can't move.
    Undo the 8mm bolt on the front number plate and drop all cables and wires under this mount.
    This give you plenty of slack for the extra height.
    You will notice that you have a plastic mount on the number plate that now has nowhere to go. Cut it off.
    [​IMG]
    When done it should look like this
    [​IMG]
    Next loosely mount the bar accessories
    Now apply a bit of gasket sealer or grip glue to the bars. Use enough that you get full coverage but don't glop it on.
    It should look like this.
    [​IMG]
    Apply your grips and wipe off the excess.
    I used carb cleaner for this.
    Now adjust everything to you liking.
    Ziptie your kill switch wire to your clutch cable below your adjuster
    Install your pad and you are done and it should look like this.
    [​IMG]
    The difference is as follows:

    2" in bar height gain.
    The factory bars with grips were 29.25" wide now they are 31.75" wide. I like wide bars for control.
    I couldn't fined a accurate way to measure the front to back change but it is so much more open. I would say my hand set 4" further forward.
    Great change and it cost $110 for all the parts from the local dealer.
    #37
  18. ROUNDSTOCK

    ROUNDSTOCK Been here awhile

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    that tab off the number plate acts as a guide for the front brake line.at full compression the line is going to hook on the back side of the plate and it will not be good!.......
    #38
  19. ggamster

    ggamster Been here awhile

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    I would agree on most bikes, but on the kx100 this isn't a possibility. The shape of the plate in conjunction with the bar pad won't allow that to happen.
    #39
  20. ggamster

    ggamster Been here awhile

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    So here is a video in my woods. It is a great fun place to ride. It was muddy but the bike had unbelievable traction. I am so much faster on this bike than I was on my KTM 125SX or on my G650X Challenge. Keep in mind I was still breaking in the engine so I couldn't get on it hard. It is so much fun. I have the 10oz fly wheel weight on now and I will post the easy how to on Wed. This bike rips!
    http://www.youtube.com/watch?v=TYj1...DvjVQa1PpcFMOSCFl7MMVP0fIaz9BYlrmlES2dji2NhQ=
    #40