The XR400 Thread

Discussion in 'Thumpers' started by Hayduke, Jan 16, 2008.

  1. jphphoto

    jphphoto jphphoto

    Joined:
    Aug 14, 2007
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    38
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    Brooklyn
    Hi folks,
    Been reading along and learning some new things to look out for on my newly acquired XR400. Got it running Sunday after some fiddling and cleaning the carbs out. Think I need a new sator rewind or Ricky's Stator since we had to resort to pushing to get it going the first time after winter hibernation. Always been a little hard to start since top end rebuild.
    My question is, Can I replace the float bowl needle and floats with the carb still on the bike? Would probably require setting float height while on the bike too. Not sure if this is possible. It's a bear to carb off and on but its leaking like a stuck pig when the fuel is on so somethings gotta be done. Flooding may be affecting starting too?

    Any advise is appreciated. I'll get some picks up once get this sorted.
    Riding Pachaug this Saturday. :D
    Jason
  2. Wallrat

    Wallrat Been here awhile

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    I'd wager that 100% of your starting issues are due to the carb and the stator is fine. The easiest way to deal with the carb is to just spend the bucks and get a pumper. It aint cheap but you get 1-2 kick starts in any weather and a nice increase on the bottom/mid range. You can tweak the stock one but if the bike has been sitting around neglected you're probably going to need a complete gasket replacement if nothing else.
  3. jphphoto

    jphphoto jphphoto

    Joined:
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    Let's hope so. I have a gasket kit and a new float needle on the way from service Honda. Once started and run it will start with a kick. Cold, not so much.
    I'll let you now how it goes.
    Thanks,
    Jason
  4. hughrk

    hughrk Adventurer

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    Set your float height after you fit the new float needle, this IMOP is the cure for most cold starting issues.

    Cheers :ear
  5. tonusmaximus

    tonusmaximus maximus

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    nky
    Am looking for a chain sprocket set. Anyone know of a good deal on a quality product? M-superstore was way too pricy and eBay doesn't have the reviews I need to convince myself..
  6. AMCJEEP

    AMCJEEP Been here awhile

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    Try www.rockymountainatvmc.com
  7. RideFreak

    RideFreak Torque Junkie

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  8. MartiniUp

    MartiniUp Long timer

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    CK the pilot jet while you are in there. Should be a 60 or 62 for best starting. Try a 160 main. They come way too lean from the factory. I would also bet three nickels the stator is just fine. I have had four XR4s and feel the stock carb is not a problem at all.
  9. hughrk

    hughrk Adventurer

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    +1
  10. wvridgerider

    wvridgerider Been here awhile

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    Wow, I wonder if it was a bad bore job? I wouldn't think it would go bad that fast.
  11. G600

    G600 Been here awhile

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    +2. Spot on.
  12. DrLewall

    DrLewall The Human GPS

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    I've told this on here before, and I don't mind telling it agn..I had starting issues with the stock carb and had it apart several time trying to figure out what the deal was.

    Had the 62 pilot jet in it and we kinda felt for some stupid reason, it just wasn't big enough. Was at my friends shop using his "carb work bench" where he rebuilds his carbs and he has a set of super tiny drill bits. Had the 62 in my hand and was looking for a drill bit that would not fit into the 62. Found one that would and got the next size bigger that would not fit. Used it to ream or drill out that 62. My best guess now would be that my converted 62 is probably a 65 or a 70 now. Since then, no starting issues! :clap It lights up now on less that 3 kicks, when before it would take 50-60 kicks.

    We don't have a clue as to why the 62 wasn't doing the job, when everyone else's 62 seemed to do :dunno But I am happy with it and it's working for me. And thats what I did to fix it.
  13. mvg2

    mvg2 Been here awhile

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    That's exactly what the guy said. Nothing to do with it going bad, it just never started out good. So if that KTM of yours ever has to go under, you may want to find a new guy.

    But even with that cylinder it still ran! Now that everything is back together I got to take it for a spin yesterday and the motor certainly is a little more snappier. :clap

    Now (always something) that I have put a new front tire on, the front end has got a annoying wobble/pulsation when riding down the road. I balanced it once, but no help. So I may rotate the tire a bit and start over....
  14. XR4EVER

    XR4EVER 919 excuses to ride!

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    Make sure the tire is "centered" in the rim lock. My usual procedure is to leave the rim lock loose and take the bike for a short spin off road around the house to let the tire self-center and settle into the rim, then I come back and tighten the rim lock. Otherwise, you can pinch too much (or not enough) of the bead inside the rim, giving you a low (or high) spot on your tire.
  15. mark1150

    mark1150 Been here awhile

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    Wisbechistan UK
    As per the header I have a couple of questions for you guys.
    The first concerns the fuel petcock; my original one was leaking past the valve when in the off position, which I replaced with a used one from e bay and that one has the same problem.
    I drilled out the rivets, and found that the diaphram had some wear on it so I turned it upside down and inside out re assembled.
    At first I thought that all was well because it holds air pressure, BUT, when on the bike it still drips fuel while in the off position.
    My question is does any one know of a diaphram that could replace this? or can one be fabricated at home, and if so what materials will I need, as officially Honda do not sell this part as the petcock is not rebuildable?.

    The second one concerns the rear mudguard / fender, what modern shaped one is available (similar to a DRZ 400) to replace the integral guard rear light?

    Thanks in advance.
    Mark.
  16. Clem Kevin

    Clem Kevin Nude With Boots

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    My shop gave me a yamaha seal for the petcock, it had four holes rather than the 2-3 that the stock honda one comes with, but I haven't had any leaking since.

    pictured here...

    [​IMG]
  17. AndyCap

    AndyCap Mineral Oil Anyone?

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    Decided to bite the bullet and get myself a Pumper carb from XR's Only. I love this bike, but it is a bitch to start, and now it won't idle worth crap. I hope this carb is as good as all the hype I have heard.
  18. wvridgerider

    wvridgerider Been here awhile

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    Hopefully it will last but will be doing the head soon. When I broke ithe 400 in I took it easy and no constant throttle. I hope this holds up for you, kinda feel bad. Tha orange bike rocks. Trying to plan a long dual sport ride this weekend.
  19. MartiniUp

    MartiniUp Long timer

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    Nothing wrong with the stock carb that proper jetting and a good fuel filter will not fix. I have had four xr4s and after jetting each and one that was severely clogged I have had zero issues.
  20. creaky

    creaky Been here awhile

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    On the flip side of that..... my son and I have had 2 400s, a '96 and an '02,still have a '96. In each case, dumping the stock carb for an aftermarket, a MIkuni 34mm flat slide non-pumper for the '96, an Edelbrock for the '02, BIG improvement across the board.