Klx 250/300 Acerbis tank How to get all the fuel out of it mod

Discussion in 'Thumpers' started by MartinDKtm, Apr 27, 2008.

  1. MartinDKtm

    MartinDKtm Been here awhile

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    Ok a few people have ask me on a few forum how I did install fuel lines in the tank and a fuel pump to gell all the fuel out of that tank so heres a small sketch and picture of the pump installed. I got the idea from a guy tha was on here, or tumper Talk or Kawasakiforums...I don't remember so I don't have to become famous because of this setup I posted.

    Ok I did not took any picture of the internal mod so I did draw on the instruction sheet of the acerbis tank to TRY to show you what I did...

    [​IMG]

    So now some explanations...first, remove petcock, 2- unscrew petcock filter #2. Now you will find a small rigid plastic tube under the filter. In the petcock you will see a small hole beside where the rigid plastic tube is insert. Thats the reserve hole. You can try to insert a line inside in it, I had to grind the line to fit it in. Or you can try to find another rigid plastic tube and insert it or cut in half the existing one...then put the line "D" +/-2" long with a 90 degree elbow with the other end in the petcock or on the other plastic tube that cut/find somewhere...I think its better not to grind the line and find cut a part of the existing one. (I will mod mine later with a second plastic line insted than inserting the line in strait in the hole, makes too mutch restriction).

    So after that you need to make the lines that will go to the bottom of the tank. You need a plastic "T" with 2 long enough piece of tubing so they can reach the bottom of the tank wings. On the last "T" connection you need to put a +/-2" long tube (line "C"). Put that assembly in the tank by the gas cap. NOW for some peoples..you got to start taking beer or pray any god that you belieive in or have a punching bag or a friend to vent off frustration...And pic the steel wire of you choice and try to push or run the lines that needs to get in the bottom of the wings as I tried to draw on the picture...Yes its possible I done it in about 15 minutes...Don't forget that gravity can be your friend.

    Once this is done, the +/-2" lines from the "T" (line "C") should point towards the petcock hole. Have another beer/pray or punch...and push that line thru the petcock hole so you can catch it from outside the tank. Plug it to the 90 degree elbow that is on the petcock and install the petcock on the tank.

    Its now over for the tank part. Fuel pump following ....
    #1
  2. MartinDKtm

    MartinDKtm Been here awhile

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    Ok fuel pump part. Now its easy. I bought a Mikuni snowmobile fuel pump. And installed it on the bike...a picture is worth a thousant words so heres the pictures...

    <a href="http://picasaweb.google.com/MartinDKtm/PhotosBikes/photo#5194005805527640946"><img src="http://lh5.ggpht.com/MartinDKtm/SBTQwtfKq3I/AAAAAAAAAD0/b5KP04OoBT0/s800/IMG_0594.JPG" /></a>

    <a href="http://picasaweb.google.com/MartinDKtm/PhotosBikes/photo#5194005869952150434"><img src="http://lh4.ggpht.com/MartinDKtm/SBTQ0dfKq6I/AAAAAAAAAEM/stSROULctDc/s800/IMG_0597.JPG" /></a>


    So I will only explain the tubing routing here...Petcock line goes to the pump input, the output of the pump to a online filter then to the carb. And the darker line you see is the vaccuum source for the pump...It is plugged to the nipple left on the front of the carb when you remove the anti pollution thing.

    So installation done. Im still experimenting that installation and its not perfect yet. I have some bubbles running in the lines somtimes so I think my pump may be faulty, Im still not sure of the vaccuum source. I may try to plug it to the crankcase vent to get the pumping action of the piston going up and down like on a 2 stroke engine or I may also try a pump that is design to run on a four stroke intake vaccum source instead of a pump design to have big succion from a 2 stroke engine base. I also want to add a second plastic tube to the petcock instead on inserting the line in the petcock hole.

    So you now have the basic idea. Refine it and post your result you may have better ideas than me...Im open to suggestions.

    Martin
    #2
  3. MartinDKtm

    MartinDKtm Been here awhile

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    The actual pump is not good. Its design for big pulse from the up and down motion of a 2 strokes pistons since its normally connected to the base. I have a 4 strokes atv vaccum pump on order that is design to run in the intake vaccuum. Ill let you know how it works.
    #3
  4. MartinDKtm

    MartinDKtm Been here awhile

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    So I got my new pump yesterday night and installed it. Now works like a charm. I end up installing an Actic-Cat Atv mikuni pump Arctic-Cat part number 0470-758. Its design for the 4 stroke intake vaccuum source.
    #4
  5. a16tony

    a16tony Been here awhile

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    Nice application. Didn't know those pumps existed.
    #5
  6. MartinDKtm

    MartinDKtm Been here awhile

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    FOr the one who wants to know...I did test the range yesterday on the road. I had put road tires on it with a winshield and did a 535 miles (700 kilometer) trip yesterday. I did 165 miles (266 kilo) before engine stall. Then switched to the reseve and went on road back back again for another 48 miles (77 kilo) befor getting to a dead stop. I had bring some spare fuel to refuel...So I did a total of 213 miles (343 kilo) on a tank. Speed was steady at 68-74 mph (110-120km/h) at 6000-6500 rpm. Bike has a 300 barrel with wiseco piston, fmf Q4 with power bomb, n1tc, 132 main, 35 pilot.
    #6
  7. DaveRMS

    DaveRMS Long timer

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    If you are looking for 2009 model issues, see this thread.

    [​IMG]
    #7
  8. redpillar

    redpillar Been here awhile

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    Thanks for the great idea, I bought the other pump and mounted it this way, I paid about 35 bucks for it. Part number is: Arctic-Cat part number 0470-758. I made a couple of different couplings for the outlet of the tank, to try to clear the choke knob. I also fed the fuel lines into the tank from the outlet hole, up and over between the holes in the side of the tank. It only took a about fifteen minutes and some mucking about to get them in. Here is a shot of the first coupling.

    [​IMG]

    This one worked the best.

    [​IMG]

    The line on the lower right goes to the vacuum port on the front of the carb. The left hand fuel line is from the tank fitting via the stock petcock and the upper right line with the inline filter goes to the carb inlet.

    [​IMG]

    Another shot with the plastic tank mounted

    [​IMG]

    Another with the choke problem solved, I used a silicone gasket maker to seal the aluminium plate to the tank outlet.

    [​IMG]

    Here is a shot of the shadow of the fuel line inside the tank.

    [​IMG]

    And another looking inside the filler hole at the tee.

    [​IMG]
    #8
  9. redpillar

    redpillar Been here awhile

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    I have had a chance to run a few tankfulls through the bike and have easily got 300 KM out of a tank with about 4 inches left in the wings, I would say I could go another 20 to 30 KM before the tank runs dry. Mostly pavement but not being gentle on the throttle.
    #9
  10. slvrblt

    slvrblt Adventurer

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    What size fuel line did you use?
    #10
  11. redpillar

    redpillar Been here awhile

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    I think it is 3/16 inside diameter but not sure. I bought some and it was too small. I wanted something I could see through to ensure fuel flow.
    #11
  12. mic_detonator

    mic_detonator ride

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    I tried today to get the two bolt holding the tank in place. And to my suprise the left one is stripped. Must have been the time i took it off an\d put it back on while doing the rebuild. any ideas it HAS to be the brass thread in the tank. I cannot seem to get around the rubber grommets though :cry .

    pm me if any one has any ideas! time to go ride, Hey at least it runs now :D could be worse.
    #12
  13. redpillar

    redpillar Been here awhile

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    Sorry....A little late on the answer but, I took the metal washer/inserts out of the rubber grommets on the frame, this gave me a bigger diameter hole to work with and I was able to get the bolts in place. I guess you could retap the threads in your tank with a bottoming tap to fix your problem.
    #13
  14. Tom Blum

    Tom Blum Been here awhile

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    hi folks!

    I bought a 2006 KLX250S last fall.

    I'm late to the party, but I have recently installed an acerbis tank and am installing the arctic cat fuel pump.

    things are going great, but I'm a bit unsure of the vacuum source. I don't "speak" carburetor like some of you and hate to jump in and get killed by my own ignorance.

    Could someone post a picture or a link to the carb with the emissions stuff removed and the vacuum port in clear sight?

    Thanks
    Tom
    #14
  15. redpillar

    redpillar Been here awhile

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  16. Tom Blum

    Tom Blum Been here awhile

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    Thanks a million Red Pillar.I had the wrong place in mind.

    I see it now."I can see clearly now"!!!

    Tom
    #16
  17. redpillar

    redpillar Been here awhile

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    You will be very happy with how it works out.
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  18. Tom Blum

    Tom Blum Been here awhile

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    incidentally, I am making one change to your approach. I am only running a siphon tube to one side.

    I'm not smart enough to do without a reserve.So, when the inevitable happens, I will tip the bike over and drain the other side across and then drive to the nearest gas station <G>

    Tom
    #18
  19. redpillar

    redpillar Been here awhile

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    Not a bad idea. It is nice to have the warning. I just use my odometer and when it reads 330 km I know I need to find fuel pretty fast.
    #19
  20. AlsXZ

    AlsXZ n00b

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    Hi there!
    I'm installing my new Acerbis tank and going to do that mods with fuel pump. I want to use only one fuel pipe to one tank wing as I want to have fuel reserve. Can you explain more detail how to connect fuel pipe (1/4" or 3/16") that going into tank's wing to petcock ? It's totally unclear for me. I have unscrewed petcock filter #2 and found thin rigid plastic tube and small hole (reserve hole). But what the next to connect fuel pipe (1/4") to it ?

    Thank you in advance, and I'm sorry for my English, it's not my native.
    #20