Any Honda Dominator NX650 owners out there ?

Discussion in 'Thumpers' started by KeithDommirider, Jul 31, 2007.

  1. 2manyrides

    2manyrides shifty charactor

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    Can't you just get a whole master cylinder cheap enough on ebay... Here's an example of one for an ascot. I'd have to look closer to see if they are the same.

    https://www.ebay.com/itm/273773857917
  2. scrambler66

    scrambler66 Been here awhile

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    there are 18mm sight glasses on ebay that fit https://forum.nx250.de/viewtopic.php?f=23&t=735 I had one at my dommie for a couple of years with no issues, but than I cleaned the reservoir with brake cleaner. Soon after that the glass broke - apparently its not resistant against alcohol.

    [​IMG]
  3. Rockman

    Rockman Been here awhile

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    Not cheap actually - shipping to Aus is $48 US!

    I have ordered an 18mm sight glass from china $1.48 and free shipping, but I expect it'll take a while to get here.
  4. 2manyrides

    2manyrides shifty charactor

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    I see...
  5. 2manyrides

    2manyrides shifty charactor

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    So, It's the new to me 89 nx I have put about 400 miles on it since I got it. Today was my longest ride on it and I ran out of gas at the end.

    I "close to almost all the way" filled it and headed out today. I got about 110 miles. But what shocked me was how very little reserve lasted. I think I got about 10 miles out of reserve. Is that about right?
  6. Griff2

    Griff2 Griff

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    Seems a bit low. Perhaps check the air filter ?
  7. mas335

    mas335 xendurist

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    does it have the original petcock?
  8. 2manyrides

    2manyrides shifty charactor

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    This bike has 8,400 miles on it. Runs and looks new. Almost stock, but has been de-smogged and re-jetted. Shamefully I admit that I've yet to take anything apart to have a look. It was a "turn key" purchase. I have not had the seat or side covers off.
    I think the p/o installed a k+n air filter. Petcock original to my knowledge, but I do not have a reference to check it against.
    When I ran out of reserve and looked in the tank, it seemed that though it only draws from the left side, it was quite efficient at emptying the whole tank out.
    IE, leaning it over wouldn't result in a little more available gas.

    The whole scenario makes me want to do some test runs to better guage how far it will go on a tank and on reserve. So I know... but I thought I'd check here. Good at drawing all gas out of the tank? How far can you go on reserve?

    In general I expected to get at least 30 miles and wasn't worried when I hit reserve, but was red in the face when it went dry.
    I am not concerned with the actual mileage I get, just how far I can go.
  9. Griff2

    Griff2 Griff

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    You won't get 30 miles from reserve but 10 is too low. Perhaps the rejet was a little on the rich side.
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  10. 2manyrides

    2manyrides shifty charactor

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    Thanks griff2
    I think I will run some out of gas tests and find out exactly what I do get.
  11. 2manyrides

    2manyrides shifty charactor

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    DSC00042 crop 2160.jpg
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  12. mas335

    mas335 xendurist

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    The question is was the tank really as full as you think it was? If you filled it while the bike was on the side stand then it was not all that full.

    There is another possibility that could make you run out of gas without much warning. Since we don't know anything about the service history we will assume everything is original. That means the very thin O ring at the base of the fuel tube inside the petcock could be leaking from decay, loss of flexibility and cracking from just plain old age, it is after all 32 years old. If the main source of fuels used in this bike have been alcohol/ethanol treated then this problem is only worsened as common O rings hate those type fuels. This condition could allow fuel to in effect "by pass" the fuel tube O ring and let fuel flow as if it was always on reserve. The portion of the fuel tube that separates the upper section from the lower half, which is the reserve intake area, would become ineffective and you would have little to no warning of being out of fuel.
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  13. 2manyrides

    2manyrides shifty charactor

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    Your assumptions mas335 are right on. This bike must of sat a lot over the years as I am the 6th owner and it now has 8,400 miles. Yet it is in real nice shape.

    If this always on reserve behavior is common to the 89nx for those reasons, then I may have that going on here. Thanks for the tip!
  14. heirhead

    heirhead worlds worst mechanic

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    Hello,
    Any easy way to get carb off for a non mechanic, or should I say a mechanic, just the worlds worst!!

    Thanks,

    hh
    wwm
  15. mas335

    mas335 xendurist

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    Sorry, No "easy" way. I didn't like the idea of moving the air intake manifold which I think the manual calls for. Instead I loosened and removed what was needed to be able to slide the airbox back and that worked for me. You would also need to remove the fuel tank and the rear tank mounting plate which is bolted to the frame. Once that is done the Carb can be lifted upwards through the frame, it was a close fit but that worked for me.

    Still not a simple task but at least I didn't have to worry about damaging the air intake manifold and possible risk a mounting screw frozen/corroded in the head. I once had two screw heads shear off from being seized or corroded into the engine casting. Since then I preferred to not try and remove screws that are not necessary and risk that happening again, if I can find a way around it I'll do that. Removing the carb on a NX is just not a easy task even for a mechanic, thankfully you don't have to do it very often.

    Why are you wanting to pull the carb?
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  16. heirhead

    heirhead worlds worst mechanic

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    Hello and thanks for responding.

    Just bought bike, not running. PO said carb was gummed up??
    Turned gas on, fuel leaked all over, been sitting long time.
    Any other ideas where to start?
    Thanks,
    PS LOVE your work!!! I thought the Transalp in Fleamkt was your handy work, beauty!

    hh
    wwm
  17. mas335

    mas335 xendurist

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    Thanks and Yes, guilty as charged. I restored that bike two owners ago. When I get a bike I like to start with the basics to make sure that everything works correctly before hunting for the bigger issues. Rebuilding the Carb on a poor to non running bike is just a good place to start. If it has been sitting a long time then look for those items that simple decay over time. The leak can be anything from fuel lines, to a float stuck, petcock may be leaking, finding the actual source of the leak is where I would start. As a rule of thumb I don't assume anything right about a bike that has been sitting and does not run. I once found harness wires that had been chewed on and some sort of nest in the airbox. I would carefully just inspect the bike and look for possible problems. I would also do the basics like change the oil and filter, new spark plug and air filter, get ride of all fuel that is in the system, drain tank, see what it looks like inside before going much further. Perhaps clean out the petcock, I have seen some amazing decay inside them which will just ruin your Carb after just overhauling it.

    Buy a genuine Honda shop manual if you don't already have one.
  18. Kolb Driver

    Kolb Driver Been here awhile

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    Thank you very much. Riding the back roads today, me on my FT500 Ascot, bro-n law on my NX, he went on reserve at 125, totally out at 132. (As he coasted into the Sunoco...) Now I know what to look for.
  19. mas335

    mas335 xendurist

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    Since I brought up the fuel tube O ring I thought I would post this image, I stumbled across it while looking for another picture. The O ring gets compressed when the petcock is tightened to the tank which it should do. But when these O rings get replaced you can see the "pancaked" effect that takes place over time. This is a Transalp petcock but the NX looks just like this when you remove one. See the small. shallow recessed area on the casting below the fuel tube, that is were the O ring drops in the area and gets compressed and seals the petcock from leaking at this point. This small O ring is all that is keeping the the tank / petcock connection from leaking.

    cl 006.jpg
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  20. 2manyrides

    2manyrides shifty charactor

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    And that oring separates reserve supplies from normal "on" fuel supply?