Who's messed with a KLX 140?

Discussion in 'Thumpers' started by stephano, Feb 23, 2011.

  1. stephano

    stephano Long timer

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    I have one for my son and its a fun little bike. We've piped it and jetted it but it certainly lacks some needed grunt. I dont even care for the jetting but I cant find anyone who's tried to fine tune their carb. It seems the 100/40 combo and adjusting the air screw is all anyone does. I'm also going to have to change the front springs soon because they feel like something off a 50.
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  2. Tsilatipac

    Tsilatipac Adventure Seeker

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    This is a bit old but my son has a KLX140L. When I first bought the bike I stumbled across a series of articles about uncorking the KLX140. It went through pipe, airbox, jetting, etc in very good detail. I saved all of the articles to my computer...then I got a new computer!!! I'm still looking for the articles.

    Basically most of the things I find are related to: remove the airbox snorkel, install a pipe, and rejet. That is basically what I plan to do. I'm looking for the articles because they played with the jetting to optimize for BBR pipe and modified airbox. Why reinvent the wheel when I'm no expert.
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  3. AWM

    AWM Beard Bros Racing

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    <!-- google_ad_section_start -->KX65 Carb on a KLX140L

    klx 140 different carburetor<!-- google_ad_section_end --> ([​IMG] <!-- BEGIN TEMPLATE: threadbit_pagelink -->1 <!-- END TEMPLATE: threadbit_pagelink --><!-- BEGIN TEMPLATE: threadbit_pagelink -->2 <!-- END TEMPLATE: threadbit_pagelink -->)
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  4. BikePilot

    BikePilot Long timer

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    Depending on how much extra power and suspension you want it might be easier to swap it for a KX100. The 140 is a great mild little trail bike, but its a long way from being a performance oriented machine. I've not owned one yet, but helped a kid at the track set his up a bit and showed him around the course. I was impressed with the KLX, I think its the best of the bikes in its class. Still its not in the same ballpark as a KX.
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  5. TNC

    TNC Candyass Camper

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    The Thumpertalk section that covers the KLX140 has a ton of mods from mild to wild over there on this bike. Quite a few people have done all manner of tweaking on this model.
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  6. stephano

    stephano Long timer

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    I agree too that the KLX140 isn't a race machine but it is one fun little trail bike. Unfortunately Kawasaki really dropped the ball by limiting its performance output sooooo much and making the suspension too soft for even a 50cc mini. So the reason I'm asking if anyone been doing more mild tweaks is because I bought this bike for my son and we thought it would be a great stepping stone before he moved up to the rocket fast KX85. Now the logic I dont understand that many seem to be OK with is.....why would I purchase a $3200 motorcycle, only to spend another $1500-$2000 trying to make it as fast as the $3500-$4000 motorcycle which is far better in every aspect and comes with better all around parts too?:huh Thats simply moronic. This is the reason I'm only willing to spend a minimal amount of money on this KLX and I dont really care about all the high dollar improvements guys claim makes the night and day difference. If we wanted a KX fast bike in a crappy heavy chassis, then things would be different.:lol3
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  7. dirtydeeds

    dirtydeeds I'm alive.

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    Anybody know if there is a larger gas tank available for the KLX140? Maybe 2.5 gallon?
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  8. Wallachian Spikes

    Wallachian Spikes Long timer

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    The KLX 140 is a purpose built trail/learners bike. My daughter has a 140 L & I've been impressed with it for what it is. It is hands down better than the XR 100 (a great bike in itself) I bought my son to learn on. The little KLX totes my 220 lbs up every hill on my property the steepest of which is around 50 degrees & ten feet high.

    The 140 L has 4 settings on the rear shock & I find number 4 to be too stiff for trail riding even with my fat a$$

    I have yet to seek any "power up" mods because my daughter is only just now getting to the point she isn't afraid of what it has from the factory. They say the Honda CRF 150 is way more of a "race bike" than the KLX. If your son is bored with the KLX perhaps it's just time to get that KX you were thinking of? My mind keeps thinking "the right tool for the job" & the KLX is not a race bike.

    Perhaps he should just enjoy honing his skills on a fantastic little trail bike for awhile. I rode under powered trailies for 5 years before my dad let me ride his F-11 250 at the age of thirteen. That bike was heavy & I could only put one foot down but, it had gobs of torque & went like a rocket, at least it seemed like it at the time.
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  9. Wallachian Spikes

    Wallachian Spikes Long timer

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    That would be AWESOME! I've found very little in after markett farkles for the KLX but, Ricochet does make a skid plate for it. I expect the KLX 140 to be in Kawasakis' line up for twenty years so more stuff should pop up eventually.

    I'd like to find a set of risers that don't bend like silly putty. Perhaps it's time to hit the dirt bike shop & find something they feel can be made to fit. At least the handle bars themselves are holding up, bent handle bars & Kawasaki used to be synonomus.
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  10. dirtydeeds

    dirtydeeds I'm alive.

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    1.5 Gallons just seems a little small. The Kwak website says the bike uses the same upper tubes as the KLX250. Does that mean a 250 tank could fit on this bike? Anyone have access to both bikes for an experiment?

    I've been thinking of putting together a little dual sport. A modern equivalent of a KE100. Which brings me to this note; whats a decent cruising speed for these little bikes? With a a 5-2, 110lb rider, would it cruise at 55mph?

    The FMF header/slip on, how much weight will it take off over the factory system?
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  11. Wallachian Spikes

    Wallachian Spikes Long timer

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    55 mph is the estimated top speed of the 140, so I doubt 55 would be a long term cruising speed even with sprocket changes. I'm guessing 30 to 40 mph would be its cruising speed, & 40 would probably only work with higher gearing.

    The KLX 140 is a purpose built beginners/trail bike & I think it's fantastic at that job. It has gobs of torque for a little bike & I have a blast on it just playing around but, it is limited. As a race bike it would be like bringing a knife to a gun fight.

    As a dual sport it could be a fuel efficient commuter for allies & back roads. That little 1.5 gallon tank seems to go on & on but, I'd still like to see the after market produce a 2 to 3 gallon cell for the KLX. I think Rocky Mountian ATV has a speedometer for the 140 but, it could have been some other catalog I saw that in.
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  12. dirtydeeds

    dirtydeeds I'm alive.

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    Looks like I may have one of these little bastards in my garage at the end of the week. :freaky

    I'm getting the machine for a nice price, so I shouldn't lose if the bike does not work out. The gf has a little KE100. It's been a good little machine. Dated now though. I'm hoping this will be a good trail bike for her. She'll love the e-start too.
    If all goes well, I might make the effort to put a DS kit on it. It would not make it legal where I live, but it would prevent a bunch of hassle on back roads.
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  13. Wallachian Spikes

    Wallachian Spikes Long timer

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    I just got a Go Pro & I shot my first video on my daughters KLX 140 L. It's no race bike but, as a trail bike it's an absolute HOOT!

    http://youtu.be/3_dbIlcepcw
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  14. dirtydeeds

    dirtydeeds I'm alive.

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    Cool.

    Just noticed that there is a 180cc big bore kit (jug and piston) and large valve head available for the 140.

    This could turn the bike into a decent travel bike for a smaller rider. It should make enough power to hit a reliable 55mph with the right gears.
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  15. Wallachian Spikes

    Wallachian Spikes Long timer

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    I answered your PM but, my computer was acting funny. Hope you got it. 180cc big bore kit? That sounds like FUN! :evil If you end up with the 180cc kit, I want to hear all about it.
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  16. dirtydeeds

    dirtydeeds I'm alive.

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    Just got your PM, thanks.

    Here is a link to the 180 kit

    And to the big valve head as well.

    I'm waiting to hear about the kit from someone that put it on their KLX150. There is a forum (asian) for guys that SM the little machines.

    I was thinking the air box mod and pipe might be first. That should open it up and take a couple pounds off too. I'll find some new jets for the stock carby. It first needs to be ridden. Then we'll see about appropriate mods. :evil
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  17. Lutz

    Lutz Fuzzy Rabbit

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    Another inmate, ZIGGYND, over on the Long term KLX250S review thread has checked this out here...unfortunately, the answer is no, the KLX250S tank is not even close to fitting on the KLX140L :cry.
    #17