DR350 Thread

Discussion in 'Thumpers' started by leonphelps, May 16, 2007.

  1. lakser

    lakser Been here awhile

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    Thats what I am thinking to be honest.
    but I really appreciate all the input from everyone.
  2. SloMo228

    SloMo228 World Class Cheapass

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    Plug looks rich to me, too. The fact that you're not having to use the choke seems to support the diagnosis, too. My DR gives me nice tan plug readings and I always have to use the choke to start, even in the summer. It'll be a bit rough until it fully warms up, but once it's warm it runs well. I run the CV carb with stock jetting and stock airbox (for now).

    And as someone who came from only liquid-cooled bikes, the DR does seem to run hot, but like others have said, that's just the way it is, being an air-cooled motor. I've never had a glowing header, though!
  3. MrPulldown

    MrPulldown Long timer

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  4. MrPulldown

    MrPulldown Long timer

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    This is true only if you really want to majorly remap the fuel output. I would not mind having FI. For most air box/exhaust mods the computer will make all the necessary adjustments on the fly. Instant roll on power, perfect air/fuel mixture at ANY altitude.

    Seems like there are carb guys and there are FI guys. For my the FI system seems easy to work with. Intake sensor, fuel injector, exhaust sensor and a computer. Each of these can be checked to see if they are working properly with a Ohm meter (except the computer). If something is bad replace it.
  5. FireDog45

    FireDog45 Mid-life crisis sufferer

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    It was hard to tell in the picture, that's why I asked. Black and moist would be rich while black and dry COULD be a fuel related issue that's been described as alcohol poisoning. People tend to run higher octane fuel thinking that its better for the engine when all that's happening is you're chemically retarding the timing (higher octane = slower burn). Add in that higher octane fuels tend to sit longer in the fuel stations plus the hygroscopic nature of the ethanol then you put it in a vehicle that doesn't get used a lot (lawn mowers, weed eaters, generators, dirt bikes...) the issues associated with bad fuel become greater.

    That's why I asked because I just went through a similar situation with a weed eater. The thing wouldn't run for crap and I was lucky to get it started. I heard about the issues with ethanol fuel in these situations and figured why not try it. I picked up some ethanol free pre-mix and the thing started on the 4th pull. Coughed and sputtered a minute then ran better than it ever has.

    It may be worth trying it before tearing into the carb, it definitely won't hurt anything. No matter what you end up doing servicing the air filter and box would be a good idea just to rule that out.
  6. thump!

    thump! Adventurer

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    There are lots of things I like about the WR250 and a couple that I don't. One of those is that the stock FI on the WR250 is VERY hard to modulate at slow speeds. It seems it's either on or off - very "jerky". Carbed bikes have a much softer transition. It's hard to ride it like a trials bike. WR fans will say, well, you just need a power commander to tune that out of it. IMO, that shouldn't be necessary on such and expensive bike.
  7. MrPulldown

    MrPulldown Long timer

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    Did not know that about the on/offness of the FI at low speed. My bike will also be rough when I chop the throttle. I looked into FI-ing our DR when I was messing with carb tuning trying to get a pumper to work. I am not back to stock CV and air box/exhaust. The thing that killed the DR350 FI project was the power demand. The kit I was going to install had a huge power draw for the fuel pump. Can't remember but it was something like 55watts. That plus the electronics and our bikes even the SE could not realistically support such systems.
  8. GaThumper

    GaThumper Road Less Traveled

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  9. DR350seKING

    DR350seKING Adventurer

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    my header pipe glows red from the motor to were the heat shield starts in a matter of minutes when it idles
  10. 2old2Bbold

    2old2Bbold was 2bold2getold

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    Yep. When I was looking into it, I found a couple of threads on here where guys spent a couple thousand $$$ and a lot of time trying to get them to run "RIGHT". It didn't seem like something I wanted to do. It should be better than that out of the box. FI isn't difficult to trouble shoot, but you have to work around the parameters of the ambient pressure, temp, timing, O2, fuel pressure, ECU, High pressure fuel pump, problems with over size tanks etc. And if that sucker screws up on you out on the trail, your walking. :huh
  11. tkent02

    tkent02 Long timer

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    There was something wrong with the one you rode. I have ridden a few of them, they worked fine. Very smooth throttle response.
  12. mwilliamshs

    mwilliamshs Been here awhile

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    I've ridden 4 wr250r's. 2 stock bikes that were notchy just above idle. Poor but liveable throttle response. 2 modified bikes, both with aftermarket EFI programmers. Both were much smoother in this range than either stock bike but neither was much more powerful till above midrange. The transition of idle to usable torque went from head-bobbing to nary a nod. A person who has only ridden a stock wr250r and then rides a tuned one will probably be spending some $ in short order. The smoothness makes the bike MUCH more manageable on rough/steep terrain. MUCH.
  13. MrPulldown

    MrPulldown Long timer

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  14. thump!

    thump! Adventurer

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    Well, that's the point isn't it. Off idle transition on the stock bike is jerky. If you ride it like a motocross bike you'd never notice. If you ride it slow in rocks and roots (i.e. eastern mountains), it's hard to manage. I rode the same bike after installation of a power commander or the like plus an aftermarket pipe. Much better... for only $800 or $900!!!

    OTOH, an old-school KLX250 was far easier to make "perfect" for my kind of riding with only minor carb tuning. Plus, if you're so inclined, you can bump the Kaw to 300cc with OEM KLX300 parts.
  15. FireDog45

    FireDog45 Mid-life crisis sufferer

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  16. Thanantos

    Thanantos Ride hard.

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    Yep, nice article.
  17. tkent02

    tkent02 Long timer

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    Yeah, right about the grins, but but they are wrong about the gas mileage.

    Mine is always better than that.
  18. DR350seKING

    DR350seKING Adventurer

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  19. tkent02

    tkent02 Long timer

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    Like the other guy said, that looks too rich already. Completely black is completely rich. What makes you think it's running too hot?

    For the other guy, the spark plug is supposed to look dry unless the engine is flooded or burning oil.
  20. veriest1

    veriest1 Minimalist Gear Hoarder

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    I think I'm going to redo my brake light/license plate setup. Do the DR350 dirt models have the same tail light lense as a DR650?

    And does anyone have one they want to get rid of?

    Sent from my HTC using magic.