Any Honda Dominator NX650 owners out there ?

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

  1. Pasoren

    Pasoren Adventurer

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    Any experience with Dave's mods on stock exhaust/air filter? I have read it may not have any effect on stock systems.
  2. Bounder

    Bounder ExternallyDisplaced

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    No idea, Mine came with a Supertrapp and I fitted a BMC filter.
    I also had a California model Carb on mine which I changed for a German market carb and I have removed the top of the airbox snorkel.
    I see at the bottom of that page they say that the mods might make it run worse with stock airfilter and exhaust.
  3. mas335

    mas335 xendurist

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    I may be selling a Acerbis NX tank soon, pm me if interested in details.
  4. adkfreeridex

    adkfreeridex Adventurer

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    I have not modified my carb yet. Reason being, if bike is stock jetted lean(at sea level), and after market mufflers are on (which should lean it out further), and I'm at 5000' I still might be a hair lean, but problems should dissipate by climbing through to 8500'. Creating a richer mixture which is what the mod will do, would only make thinks worse up high. I think. My bike feels like it has plenty power at 5000'. But the 35mpg(at best) seems 10-15 low. This is the only motorcycle if ridden besides a gs1200r, so I don't have anything to go by in terms of power. It won't wheelie, not sure a properly tuned one can, but if that's an indicator I hope it helps. I'm inclined to try Dave's mods, but don't want to permanently alter anything if I don't have to. Thanks!


    Forgot to add that someone before me Desmogged it but left oil separator on
  5. adkfreeridex

    adkfreeridex Adventurer

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    [​IMG]

    [​IMG]

    here are two pics of the plug (one with flash and one without), i tried to compare them with photos of plugs on the internet and my conclusion is that im running lean, can anyone confirm this? however, If i am running lean, why does my problem get worse with altitude?
  6. Bounder

    Bounder ExternallyDisplaced

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    I can't answer any altitude questions.
    But looking at the available specs from the XR650L engine it would seem that the usual jetting for over 5000ft is 55 pilot and 155 main,
    All bikes are different, but I would strongly recommend Daves Mods its not just richer its also the way the mixture is delivered at different throttle openings.
    Raising the needle is easy enough and reversable if necessary,
    What condition is your air filter in? Its easy for them to get all clogged up with the oil mist in the airbox.
  7. jeepinjeffery

    jeepinjeffery n00b

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    Utah
    Just found this site, again. I'm going to read all the previous posts but I am about to pull my Dominator out of storage and prep for riding this season. :clap
  8. adkfreeridex

    adkfreeridex Adventurer

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    So in an effort to try and find the cause of my poor mileage and loss of power, I adjusted my valve clearances. All were pretty close to spec, but the right exhaust took about five full turns out before I could get the gauge in. I buttoned everything back up, and the bike runs good, seems smoother but it could be because I want it to. But now I'm getting loud tapping from what I think is right exhaust valve. I have searched and found that it is connected to a decompression unit and that my method for clearance wont work. can anyone tell me how to properly set the clearance on this valve? Thanks!
  9. FLICKIT

    FLICKIT Long timer

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    You need to turn the engine just past TDC (top-dead-center) so the decompresser releases that valve before you check it ;)

    EDIT:
    From memory you usally hear a "clack" as the decompresser lets go, you only need to go about 5 degrees past TDC...

    With the valve loose as it is now, you should be able to turn the engine past TDC and see when the gap opens up to know when the decompresser has let go...

    Good luck :)
  10. FLICKIT

    FLICKIT Long timer

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    How bad is your mileage? (just out of interest)

    My bike ran great... but mileage varied a heap depending on how hard I was pushing it...

    Best was around 20Km/L (47mpg) when cruising slow n easy ...
    Worse was around 13Km/L (31mpg) when hammering it around offroad...
    (average was 16-17Km/L (39mpg) when cruising around the forests without hammering it too hard)
  11. adkfreeridex

    adkfreeridex Adventurer

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    I get 32-34 mpg no matter how I ride the bike around town. I will be satisfied if I can get 40.

    Flick, thanks for the tips on that valve. Bike is back together and it sounds and runs good. It seems be accelerate quicker and throttle response is snappier, it also seems to chug less at low rpms. I hope this helps my fuel economy. The guy at the parts place looked at my plug, and with mods bike has recommended a 165 main. Ill run ~50 miles with valve adjustment and re calculate mileage to see if it will help. If not ill try that bigger main.
  12. Dr LC8

    Dr LC8 ...soon or later

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    Location:
    Manchester...but from Rome!
    Any chance to find one still around for sale?

    Nic
  13. Skapegoat

    Skapegoat Adventurer

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    I assume your air pump on your carb is working correctly?
    Where the throttle cables attach to the carb is like a cam, there should be an arm with a rubber tip tracking along this.
    Sometimes these arms stick open with dirt/corrosion etc.
    Mine ran like a sick puppy until I realized this was the problem.

    Now it's much better!
  14. Carlossal

    Carlossal Professional dreamer

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    Mid North Coast, NSW, Aus
    Hi all,

    Posted on here a coupla years ago but have been lurking ever since. Still have an '89 Dominator with about a million k's on it but have a couple of tech questions:
    1) I'm reading the workshop manual trying to pull my forks to pieces to check bushes as I'm replacing fork seals and oil. I've removed the fork slider socket bolt (on the bottom of the forks - allen bolt with copper washer) and now the fork piston and return spring have slid out the top. The manual says to move the fork slider in and out, "tapping the bushing lightly" until fork tube and fork slider separate. Does this mean, just keep working it in and out until they separate - the slider pulling out the bushing? I can't see any other way I can tap it.

    2) I have the brake off too, and am trying to replace the pads. I say trying because I successfully took the old pads out, but now the new ones won't fit in :huh. I suspect my piston is very very sticky, and wondering how people get around this. Put the old pad back in and hit it with a drift? Soak the whole lot in WD-40? I did stick a screwdriver in there when I was taking the old pads out; but didn't notice that the pistons didn't move. I notice now :D

    Any help much appreciated. I was getting spongy braking, really soft suspension and repeated diving and rising on braking, so figured suspension and brakes both needed work. I'm replacing disk as well as pads, but wasn't planning to do any more on the suspension than fork oil and seals.
  15. MartinPetren

    MartinPetren Swedish Adventurer

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    Hi everyone, I have a NX650 from '91 that has a blown rear shock. I am currently searching thru Ebay for a used one. Is there by any chance any other shock from another model or brand that also fits?

    I hope to get some advice as I'm sure the bike is still bouncing up and down in the garage from today's ride.

    Thanks in advance!
  16. FLICKIT

    FLICKIT Long timer

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    I put the fork leg in a vice with some rag around it and pulled the inner slider in and out so the bottom of the slider hits against the seal, I started with taps but it took hard yanks to break the seals loose and get them out, I had to be fairly brutal, who-ever put them in didn't put any grease around them... also, make sure you remove the circlip that sits above the oil seal, under the dust seal....

    I had the same issue getting the piston to go back in... I put the old piston side pad back in and squeezed with a F-clamp while cracking the bleed nipple open, .... Don't try pushing the piston back in by putting force straight on the face of the piston, for heat insulation they have a thin metal covered fiberglass disk on the end of the piston that could easily be damaged...

    I always had a fairly spongy front brake... I suspect it was due to the old rubber brake hose expanding... If your brake overhaul doesn't fix the issue it might be worth trying a braided brake hose...

    Good Luck :)
  17. Honda Scoot

    Honda Scoot Time To Ride

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    See the rear shock post that I have adding info:
    http://advrider.com/forums/showpost.php?p=20773556&postcount=2770
  18. adkfreeridex

    adkfreeridex Adventurer

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    Mar 29, 2011
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    So the valve adjustment increased mileage by about 1 mpg. I got 35 for the last 70 miles. I threw in the 165 main, an the engine ran down here (5000') like it does at 8000' with the 155. I think I'll try a 150 main. Also, what is the function of mixing screw, I can't seem to notice what it does when I adjust it. Also, my carb kit came with two o-rings one for the tip of mixing screw near the spring and another is supposed to go somewhere on shaft according to the parts diagram but I can't figure out where, it is also a larger diameter. There was no existing one to compare to. Any recommendations on a high flow air filter? Can anyone else think why my mileage is so bad? I can incorrect jetting really throw off mileage by 15mpg?
  19. Honda Scoot

    Honda Scoot Time To Ride

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  20. dstriffler

    dstriffler Been here awhile

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    Can't wait to see it finished! :D