NX250 Thread -- official ADV owners manual

Discussion in 'Thumpers' started by valvecrusher, Mar 17, 2008.

  1. scrambler66

    scrambler66 Been here awhile

    Joined:
    Oct 5, 2011
    Oddometer:
    346
    Location:
    Germany
    Hi,

    I don't think its the CDI. In this case it wouldn`t start at all for a while and then suddenly fire up. After starting the cold engine, is the rev very low, even with choke? Then you can try to raise the choke engine idle. Just screw in the slotted screw a bit, 1/4 rev would be a good start. With a tool build from a little screw-driver that can be done even without pulling out the carb.
    [​IMG]
    By the way: imo there is a mistake in my 1988 factory manual. Here this srew is supposed for setting the free play of the accelerating pump.

    Cheers, Michael


    [​IMG]
  2. valvecrusher

    valvecrusher tractus pro pensio™

    Joined:
    Feb 15, 2007
    Oddometer:
    1,764
    Location:
    Dos Circlos
    I ALWAYS, always(repeat:always) have to twist the thottle(pump it) about 5-10 twists on each cold start...after i've ridden the bike (that day) i can usually just hit the button, and it fires..
    That being said, i usually twist the throttle unconsciously even after riding earlier that same day...

    The Accelerator Pump (AP) style carb here in the U.S. is for emissions, and overall, it's a lean setup
    until you twist(pump) the grip.

    You can read up(google) Edelbrock quicksilver carb for reviews on this particular style carb. and it's characteristics..
    The NX carb is not an Edelbrock, but the Edelbrock Quicksilver IS an A.P. style carb, not a CV style(constant velocity)
    They just have different power characters, and the A.P. style doesn't start as quickly as a CV style...imho


    gasoline today is much different than what was coming in the pumps back in the mid 80s, when Honda designed the (MD21) NX/AX-1/XL250 degree engine.~
    (much less volatility, and BTU's in today's 2012 gasoline)


    The A.P. style carb is for higher efficiency...
    It gives a 'quick squirt' of additional gas when you twist the throttle...so it is generally lean,
    and when you grab some throttle, it gives extra fuel at that very instant, but then goes back to normal metering of fuel(lean-ish)...so it's a little more frugal than most carbs...



    On a different useless tidbit:
    The ALL time best carbs were the dual carbs off the XL/XR's, and some TT'sXTs?...
    between 100-125 mpgs:deal, and it was EVEN faster (by far) than the NX powerplant....
    it's the XR vibrations(at 3k+ rpms that suck....so pretty much at any running speed)
    make a DualCarb NX manifold~setup...well...who is crazy enough for that?..:norton
  3. showallen

    showallen Adventurer

    Joined:
    Dec 6, 2011
    Oddometer:
    14

    I have to prime it 5-7 twists hit the start and it runs and dies I repeat this process about 10-15 times until it will run. Also I have the choke on full this whole time. After 20 min of running consistently I can turn off the choke... This is 30 F temp.
  4. valvecrusher

    valvecrusher tractus pro pensio™

    Joined:
    Feb 15, 2007
    Oddometer:
    1,764
    Location:
    Dos Circlos
    hmmmm

    that does sounds suspicious


    I've ridden (alot) at 30F, and i can agree that i can ride around with the choke on for 4-6 mins, up to 10 minutes...without turning off the choke..(so that is normal in the extreme cold for AP carbs, then run lean)

    And sometimes the NX will start, and then die a few times in that sort of temperatures..


    *ok, just read about your bike having 2500 miles(is it a Ross White '90?) and that you took your carb 'apart and cleaned' it.
    So you should have great compression, and assuming you did the other 'normal' maintenance.....
    1. new spark plug(gapped correctly)
    2. clean air filter
    3. cleaned the electrical grounds
    4. made sure connections were good and tight

    It's still sounding sort of like a CDI acting up...(but nowhere near conclusive)

    1.When the bike is cold(start) have you checked for bright blue spark?
    1a.have you pulled the spark plug, and hit the starter?(describe the spark initially, and 30revolutions in,50 rev.s in...)
    2.What oHm reading do you get off the pulse generator?

    Before replying, i can also guess that as sensitive as the A.P. carb is on the NX, you might have something adjusted incorrectly...

    being off even a little bit in idle speed will also make it not run well cold..
    IDLE speed correctly set is: 1300rpms ±100
    .
  5. Goofy Footer

    Goofy Footer Been here awhile

    Joined:
    Jan 28, 2011
    Oddometer:
    575
    Location:
    San Diego
    So I pulled my carb today. Looks clean but I'll still use carb cleaner and compressed air on it.
    The jetting is #42 and #138.
    Not sure if that has anything to do with my mid-rpm-range bog. I don't know what exact rpm the bog was occur as I have no tach/speedo nor dash! ha

    I'm going to the shop to see if they have a #38 and #142 or #145.
  6. PTC

    PTC Turd polisher

    Joined:
    Nov 20, 2008
    Oddometer:
    316
    Location:
    masshole mofo
  7. RollingJ

    RollingJ The mud in your eye

    Joined:
    Jun 4, 2010
    Oddometer:
    236
    Location:
    Bastrop, tx
    I have 42/145 and my bike runs great at 600ft.
  8. showallen

    showallen Adventurer

    Joined:
    Dec 6, 2011
    Oddometer:
    14

    Yes I do have 2500 miles but mine is a blue 89. I have checked for spark it checks out. I don't recall how intense the blue was. I will check the pulse generator soon. I do have a update that might help in figuring this out. Today I went to start it and was experimenting with the choke level and it would fire when the choke was only 1/4-1/2 on. If they choke was full on it would not fire and just crank over. I still had to do the 5-10 prime with the throttle. But I could actually get it to run for 2-3 sec with the choke 1/2 way on. And this is on a cold engine in 30 F temp.
  9. CurtW

    CurtW Thumper

    Joined:
    Jun 26, 2009
    Oddometer:
    62
    Location:
    Houston, TX
    Well, I can report that the CDI works fine. Something tells me there were multiple issues with the old one, as the idle speed jumped up ~500 rpm, and the whole system seems to be idling at a lower voltage (12.2).
  10. valvecrusher

    valvecrusher tractus pro pensio™

    Joined:
    Feb 15, 2007
    Oddometer:
    1,764
    Location:
    Dos Circlos
    CurtW ~ *added* the Ebay CDI to FAQs post#14...



    if at ANY time it develops issues, please PM me..

    hesitant to post things like this, and if it fails,
    don't want to be responsible for continuing to suggest it for NX'ers..
    So, please continue to update us, just as you did,(thank you) and that being said...

    AWESOME!
    Glad it works, and wish you the best with it!
  11. Jacl-Kampuchea

    Jacl-Kampuchea Booze Merchant

    Joined:
    Sep 27, 2010
    Oddometer:
    772
    Location:
    I see Drunk People.
    [​IMG]

    Small detour on the way to the coffee shop.

    [​IMG]

    The descent was even more fun:)
  12. CurtW

    CurtW Thumper

    Joined:
    Jun 26, 2009
    Oddometer:
    62
    Location:
    Houston, TX
    Wilco.

    As a side effect, as I had my hand in the frame, adjusting the idle, I felt a breeze. Found a big slit in my crankcase vent hose. STILL not riding...:cry
  13. scrambler66

    scrambler66 Been here awhile

    Joined:
    Oct 5, 2011
    Oddometer:
    346
    Location:
    Germany
    Probably everyone who tried to use a taller handle bar had the same problem: the clutch cable is too short, especially with a jacked up front fender. The stock length was just sufficient for a rather flat Acerbis handlebar. But since that required narrow bending of the clutch cable, pulling the clutch was rather hard.
    The first try, a XL250 cable failed. The length was ok, but it lacks the pipe bend the original NX cable has at the lower end. This was probably the reason that pulling the clutch with the XL250 cable was also hard.

    [​IMG]



    A cable from a Kawasaki GT550 (1983-1988, the version from 1989 onwards is too short and without the pipe bend) proved perfect. It’s about 8cm longer and it’s bended at the lower end.

    [​IMG]


    There is also a pipe bend at the top end of the GT550 cable, rather beneficial, since this way the cable is already forced in the right direction. Pulling the clutch is easy, just as stock, and now I can finally use a higher handlebar.







    [​IMG]



    I got this cable for about 16$ (plus shipping & taxes) from blitz for bikes http://www.ebay.de/itm/180822649090?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 , thus I do not know the OEM number.


    [​IMG]
  14. valvecrusher

    valvecrusher tractus pro pensio™

    Joined:
    Feb 15, 2007
    Oddometer:
    1,764
    Location:
    Dos Circlos
    Great find, sir!
    A LOT of NX'er's are going to be very very pleased..

    Please show OEM Kawasaki part number, or PM it to me(so i can include it on the FAQs)..thank you





    Added this to the front page FAQs #14 post, also added to 'Mods' post#1
    thank you :thumb

    needed this myself!
  15. IheartmyNx

    IheartmyNx Ihave2draft

    Joined:
    Apr 10, 2009
    Oddometer:
    3,859
    Location:
    Nashville TN, no chit, police state.
    SPOTTED!!!!

    Black NX250 burning it up on the show "Criminal Minds"...

    Episode: "Psychodrama".


    I think the rider was Pex... :evil Have a look at the getaway scene and you'll see what I mean lol.


    They dubbed the sound tho :-/


    VDA: Viewer Discretion Advised:


    20:33 :clap

    http://www.youtube.com/watch?v=9D2P0XrqwKQ
  16. ArthDuro

    ArthDuro quarantined

    Joined:
    Apr 12, 2008
    Oddometer:
    3,045
    Location:
    Westsideistan


    :rofl
    nice riding
  17. ArthDuro

    ArthDuro quarantined

    Joined:
    Apr 12, 2008
    Oddometer:
    3,045
    Location:
    Westsideistan
    Part number seems to be listed here
    http://www.cmsnl.com/products/cable-clutch_540111164/
  18. valvecrusher

    valvecrusher tractus pro pensio™

    Joined:
    Feb 15, 2007
    Oddometer:
    1,764
    Location:
    Dos Circlos
    Thanks ArthDuro..added to FAQs#14.





    IheartMyNX, check your pm's.

    There are only two things i ask about this thread...
    Don't start anything with 1. 'A' or a 2. Greek letter 'K' by name

    Don't take it personally, i nearly posted one 'familiar' photo, myself...:lol3

    Being they violated ADVrider terms of use, they do not exist here

    ______________________________________________________


    Thanks for the link...Good eye..
    *added* to the 'spotted in film and TV' section'...

    Yep, a new section!
    Front page, post #1, bottom.




    now if i could only recall that one 90s(80s?) movie where the girl is riding the '90 Seafoam/teal, and white one...
    they try to get away, the lady rides the NX

    Was it 'Cool as Ice'?
  19. Goofy Footer

    Goofy Footer Been here awhile

    Joined:
    Jan 28, 2011
    Oddometer:
    575
    Location:
    San Diego
    Hey CurtW, from your report my friend replaced his CDI too and it works fine. He said its a slightly different shape (shorter and fatter) but it fits. Thanks!
  20. thirstybuck

    thirstybuck Adventurer

    Joined:
    Jun 14, 2011
    Oddometer:
    82
    Location:
    USA
    I dragged the Honda out of the basement today. The battery was dead so I had to give a push start down the street. Why didn't they make this bike with a kick starter too?? I put in a new speedo gear and somehow the speedo is still not working. I will need to take the wheel off to see if I managed to shred my ($25) cog.

    [​IMG]