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NX250 Thread -- official ADV owners manual

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

  1. scrambler66

    scrambler66 Been here awhile

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    Thanks for the flattery :D

    I'm not sure about the XR250 frontwheel, the axel diameter might be different? the XL350R/XL600R front wheels are plug and play http://forum.nx250.de/viewtopic.php?f=20&t=864

    In the rear I have not found a plug and play solution for the AX1 swing-arm. A KTM 620/640 wheel can be used with new spacers http://forum.nx250.de/viewtopic.php?f=20&t=1572
    PTC likes this.
  2. jimmatas

    jimmatas OutdoorMechanic

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    Thanks a lot! It is going to be a bit tricky i reckon but my priority now is finding some wheels because it seems that there arent any here locally in greece.
    About the axle on the front you are correct! Honda nx/ax1 front is 15mm and the rear 17mm.
  3. scrambler66

    scrambler66 Been here awhile

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    I forgot to mention one option - you could take the NX250 (steel) swingarm for drum brake wheels - than you could use the 17'' XL350R rear wheel
  4. Jblok

    Jblok Been here awhile

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    did anyone lower there footpegs, if so how did you do this?
  5. Jblok

    Jblok Been here awhile

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    You think that a bigger main het is needed for this mod?
    would be perfect since #145 seems slightly to big for my nx
  6. Zic00

    Zic00 n00b

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    hey guys, anyone manage to get a front disc guard on? ive seen pictures of it being done but i cant find anything online. would the acerbis Xbrake fit?
  7. valvecrusher

    valvecrusher tractus pro pensio™

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    It depends on your Altitude above sea level, your compression ratio, your cam timing, exhaust system backpressure,
    and your fuel....
    Other than that, :lol3
    it's probably fine stock. lol
    $.02

    I think the bottleneck in the NX power is the airbox opening, and the Typical Honda quiet muffler..

    Now, if your muffler is 'blown out', and the airbox is opened up, well, it is still hard to determine..

    What does your spark plug look like?


    I opened my airbox with about 80 holes, used a K&N filter (instead of sheet foam like MuddyRabbit's picture),
    and my muff-less(muffler) sounds like a Beast on a Trumpet screaming demon songs of Hell.

    But my fueling is PERFECT at 500-3000 feet elevation, lugs a little at 6700 feet elevation, fueling gets a little rich...
    (on a stock jet)
    your results might vary.
    :-)
  8. Too Old for This

    Too Old for This Adventurer

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    jimmatas, PTC, Spurlock and 2 others like this.
  9. eldomike

    eldomike Who Cares Supporter

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    I could use a headlight cowl for a 1988 NX250 if anyone has a extra one...color not important
  10. DEEPSIX-1

    DEEPSIX-1 n00b

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    Hey all, I'm thinking of parting out my NX250 just so I can buy a newer bike that doesn't require as much tinkering, as its my first motorcycle. I have every part for a 1989 NX250 except the side fairings and front brake setup (they're NISSIN but setup for NX250 and would be willing to sell). If there is enough interest in parts I'll sell them all off. I have a full working engine, carburetor, gas tank with no dents, full rear fender assembly except for the top cowl, pretty much everything. Let me know if you're interested in any parts.
  11. Spurlock

    Spurlock Long timer

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    Nice weather in the Napa Valley wine country today.

    [​IMG]

    -Bill
  12. valvecrusher

    valvecrusher tractus pro pensio™

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    @Spurlock @Too Old for This

    I admire both of your excellent creations and executions of 'home built chain sliders.'

    I understand it is 'too late' to measure the hole to holes, and index lengths for the 'side tabs' etc....
    But is there any chance you might be able to 'back into' these measurements for Future NX250 Owners' Needs...

    ? Like if you started with a 2" wide sheet of HDPE, or Teflon impregnated plastics, in a sheet...
    It would be a specific length from x to y, and put your holes at Z, side tabs A and B....
    THEN bend it with the heat...

    Thank you for allowing me to make this request...

    b
  13. Spurlock

    Spurlock Long timer

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    Good idea. I actually wanted to do that but found that the plastic stretches a bit during heating/bending around the swing arm, changing initial guesses on hole locations somewhat. But I think it would work well to complete one of the holes for the oval mounting washer but leave the other mounting area oversized and not drilled. Then screw the one mount to the swing arm, heat and make the middle bend, then locate the second mounting hole to line up correctly.

    If I ever need to remove my swing arm again I will do that, but right now I have no reason to tear down again. Maybe if my buddy's slider fails I will have a chance to figure out a pattern as above.

    -Bill
    valvecrusher likes this.
  14. Citronodlaren

    Citronodlaren Adventurer

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    About 21" front wheel, I have it on my bike, be aware that space between tire and fork brace is tight. It do not allow for anything but the skinniest tires. I have a 80/90 tire and that work but something could easily jam between tire and brace. It was like this when I got it. I am going to fit the 19" wheel back again as it came with the bike as well.
  15. Jblok

    Jblok Been here awhile

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    Guys and galls,

    trouble on the Nx,
    I did an oil change (10w40 full synthetic) and now she smokes on start ups.
    Probably a leak valve seal, but I do suspect the the full synthetic oil to be part of this problem, any body had the same troubles?

    also I might try one of those seal conditioner additives.
  16. PTC

    PTC Turd polisher

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    masshole mofo
    Don’t use an addictive, for your bikes sake. If you were stuck in the desert being hunted by zombies, sure use one. They turn rubber and plastic to mush. Yes it will swell the seal. But it will also weaken it to the point that it can be liquified and do terrible damage. ALL the rubber and plastics in contact with oil will be harmed.
    That said... it didn’t smoke before the oil change??
    Going from conventional to synthetic won’t cause a valve seal leak.
    valvecrusher likes this.
  17. valvecrusher

    valvecrusher tractus pro pensio™

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    You may have OVER-filled the NX with too much oil?

    When you check the oil dipstick on the NX250, the bike must be UPRIGHT,
    NOT leaning on the kickstand.


    If the bike takes 1.5 liters, and you put in 1.9 liters, smoking is a possible result.(some are more picky than others.)

    I'll let the smart guys chime in next.

    v
  18. Jblok

    Jblok Been here awhile

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    I checked again today, oil level with the bike straight up is on 3/4 of the dipstick.

    to be clear, set the bij straight up, dip the stick, do not turn the dipstick in and then check.
  19. valvecrusher

    valvecrusher tractus pro pensio™

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    I do it like this for a 'quick check',
    then screw it in for 'fine tuning', or precise measurement..

    If the bike is upright, and the oil level is between the UPPER and LOWER both times/both ways,
    I'm happy with it..






    with the bike straight up, it should only go APPROXIMATELY 10mm from the bottom end....
    There are 'index marks'(FULL is upper, ADD is lower)
    on the 'scale',
    and the scale is on the bottom of the stick...
    [​IMG]

    See the Two Lines (bumps) on the bottom(flat end) of the dipstick?
    The lines are on the flattened end, both of them....

    The upper line is FULL, and the lower line is ADD OIL(too low)

    If your oil level goes up past the rounded part of the stem, its WAY high...
    and overfilling the crankcase will cause smoking BAD..on any combustion engine..


    It needs to be between those lines on the flat end,
    with the bike straight upright, as if you were riding it...

    And the NX only holds 1.6 liters of oil, total.

    I'm sorry for the difficulty of my poor explanation, I barely speak English well
    v
  20. scrambler66

    scrambler66 Been here awhile

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    Have you checked the crankcase breather? It has to be drained every 6000km or the condensate will back float into the air filter box. Usually, especially when driving in wet conditions, a lot of water and few oil is coming out of that breather tube. If you filled in too much oil a lot of oil is coming out of that tube I guess (haven’t tried that though :D).


    [​IMG]

    In that case the air filter box has to be checked – there is likely also a lot of oil inside (usually its dry) which has to be removed.

    [​IMG]