DR350 Thread

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

  1. heirhead

    heirhead Been here awhile

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    Hello,

    Bet $.05 its the cap, as have had same thing happen twice, with brand new plastic tanks.
    Hope it is. Good luck.

    Heirhead
  2. MrPulldown

    MrPulldown Long timer

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    The acerbis cap is vented.
  3. Anonawesome

    Anonawesome Scenic Rider

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    Just an idea. The petcock on the stock tank is vacuum operated with a hose running to the carb. Whereas the acerbis petcocks are not. Not sure if the pumper carb has this since I just ordered one, but you could have an open vacuum line on the side of the carb, which would need to be capped.
  4. Greg Bender

    Greg Bender Long timer

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    This is true for the CV carb, but not for the pumper carb. The petcock for the pumper carb is the simple on/off/reserve affair with no vacuum connections whatsoever.

    Regards,

    Gregory Bender
  5. dav_dman

    dav_dman Been here awhile

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    its SUPPOSED to be. Unless the mold line has flash and it's blocking the vent, etc.

    i actually had a plasic tee that was blocked from that once that caused my magna not to vent and leave me stranded a few blocks from home.

    Just pull the cap with your ear down close and you'll hear it when you open it. Could also run it with the cap cocked slightly and you'll know pretty quickly...a bit dangerous but not if you're careful
  6. Greg Bender

    Greg Bender Long timer

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    I'm not so sure the pumper is toast. When I decided to replace my old pumper, the symptom that was most annoying me was the inability to return to idle, especially when warm. It still ran pretty good throughout the throttle range, but it would "hang" at high idle. As soon as I fit a new pumper (same jetting), all was right with the world and I also enjoyed a small improvement throughout the throttle range that I had not even noticed before. From the video I viewed, the symptom's with RuggedExposure's DR350 are not similar to my symptoms.

    A worn slide will allow more air in, causing a lean condition, and thereby raising the revs. A worn slide should not, in and of itself, generate a rich condition (at least I am not seeing how that could happen).

    RuggedExposure, I completely understand your frustration, as mechanical bits have gotten the best of me many times over the years. As others have said, I too believe the problem is very simple. I would encourage you not to give up and not to use the DR for target practice.

    I was at a Guzzi rally a number of years ago and a guy had a beautiful Eldorado with a custom paint job. Stunning, really, and I don't say that very often about custom paint jobs on the Eldorados (most leave me with a bland taste in my mouth). The Eldorado would not run correctly. A few of us fiddled with it some (at lot of loose ground wires, etc) and it ran better. But, the owner was frustrated and traded it straight up for a Moto Guzzi SP1000. The SP1000 is a fine machine, but this example was not the equal of the Eldorado (not by a long shot in my opinion). Once home, the new owner of the Eldorado replaced a $3 condensor and the Eldorado ran beautifully.

    For those who don't know, last year I swapped the nearly new pumper carb on my DR350 for a CV carb. My goal was to obtain additional range with my Clark tank without a need to carry additional fuel. I met that goal and remain very satisfied with the performance of my CV carb. Shortly before leaving for a dual sport rally in Nevada, I had fiddled with the CV carb for some reason or the other and I was certain it was reassembled properly. But, it wouldn't run properly. It took *forever* to warm up and then it would cut out horribly starting at mid throttle. I was convinced it was fuel mixture screw or a need for different jetting or some such other problem (CDI, coil, etc). I thought I had it fixed and was all packed up and leaving when the problem reared it's ugly head not a 1/2 mile down the road. It wouldn't pull 50 MPH. Frustrated, disgusted, wasting hours dealing with this on a vacation day, not fun. I replaced the CDI and tested - no change. I replaced the coil and tested - no change. I replaced the spark plug and tested - no change. I replaced the voltage regulator and tested - no change. Finally, I tossed on the pumper carb and the problem was immediately gone. I didn't take the time to investigate the CV then and there (I was off to Nevada), but I later discovered I had failed to seat the rubber diaphragm properly on the top of the CV carb. I had a HUGE air leak and the slide simply wasn't raising to permit more fuel/air into the engine. A simple problem caused by yours truly that took me many hours to sort out.

    Here is a thought on something to check - are you certain that the choke (an enricher, really) is sealing when it is closed? You might take a look at that just to see. It could be that it is continuing to dump fuel into the circuit even when it is physically closed. If memory serves, there is an o-ring to seal the enricher to the body of the carburetor, and then a rubber seal on the front of the "piston" that closes the passageway??? Sorry, I'm a bit hazy on those details. Anyway, that is something to check.

    Don't give up! Hope this helps :>

    Regards,

    Gregory Bender
  7. jmderyke

    jmderyke Miner

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  8. dav_dman

    dav_dman Been here awhile

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    Agree. And sometimes it's good to take a break for a day or two and go riding or do something else then come back to it a little less aggravated with it.
  9. cwc

    cwc Been here awhile

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    I think there might be some significant wiring harness issues trying to adapt different electrical parts. I've no experience with the DR250 so probably shouldn't offer advice on that.

    On the other hand the ignition system draws very little current, so if you had a charging system failure you could just run off the battery charging it occasionally. You would want to unplug the lights.

    If you really want part interchangeability you should consider a 98-99 DR350 instead of the DR250. The earlier e-start 350's have different parts such as sprockets, rear wheels, wheel bearings etc.

    On the other hand, you aren't going that far and if everything is in good shape now you probably won't need anything.

    AND, you really don't want to carry all that stuff with you.:deal
  10. RuggedExposure

    RuggedExposure Now with more rugged

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    FI is supreme in my book. Almost every carbed bike I've owned has givin me hell and ended up being the demise of those bikes. I started out with a '94 Kawa Vulcan 750. It was incredibly fast for such an old heavy bike, but it would not start if the bike was cold. It would not start if the bike was hot, would not start on any sort of an incline/decline. Even the local stealership couldn't figure that one out. I ended up parting it out on ebay.

    I had an '05 Honda Shadow 750 that was great, luckily the carb never gave me many problems on that one.

    My '98 KTM 620 developed carb problems and ended up getting traded.

    The '03 Yamaha TTR I just sold last week was traded to me since it had carb problems. I worked the gremlins out of it to where it was more reliable, but it still had some ghosts.

    I have an '08 Kawa MeanStreak 1600 with FI and nearly 20k miles on it. Since the day I bought that bike I have thrashed it, modified it, and put it through hell. But it still goes like a champ and passes almost anything on the road, except for the gas station.

    I cannot wait for my tax return so I can drive my happy ass with cash in hand over to Tuscon or Albuquerque (both are 4 hours away) and get a Terra 650.

    I will give this a shot by taking the cap off and stuffing a rag in there to ride around.

    I have the carb completely apart and sitting in a citric acid solution since yesterday. I will also poke through the passages with a torch tip cleaner (carefully) to make sure no grit or sand is lodged in there and reassemble to see if anything if it helps.

    ya, you're right. But its incredibly frustrating for me considering that I'm having to drive my truck or wife's car to work everyday when I should be riding this suzuki on my hour long commute to save some money.

    Don't get me wrong, I enjoy taking things apart to see how they work and fixing them when they go bad. But when something is down for months on end, and seems to stop working for no reason because the motorcycle gods have frowned upon my bike, it chaps my ass. I make too much money to have a junker that gets worked on more than it gets ridden, and its worth more to me to throw money at the problem and fix it than spend time working on it to no avail. I work a 50-60 hour week and have 2 hours drive time in my commute everyday. My spare time is worth gold to me.

    If ammo wasn't so scarce right now this bike would be my new target stand out in the pasture.

    Thanks for the encouragement guys, I will keep trying.
  11. mouthfulloflake

    mouthfulloflake Not afraid

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    I had forgotten its an enrichment circuit and not a choke flap

    I think bender is on it.

    thats pretty much the only way for it to be so rich if the jets are in fact screwed into place in the carb body, and the needle is in fact not being prevented from dropping down all the way for some reason.
  12. RuggedExposure

    RuggedExposure Now with more rugged

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    I meticulously reassembled the carb, and cleaned every jet, orifice, nook, cranny, hole, and surface.
    Installed it on the bike, and it fired up immediately.
    Idled fine with the choke pulled out, warmed up nicely.
    Took it for a spin, and right away it began getting flooded again...

    Before it had a chance to cool I yanked the carb off. once again the intake was wet with fuel, and smoke poured out of the intake.

    I decided to give the carb a sort of bench test by hooking it up to the tank but leaving it off the bike so I could see what it is doing.

    Hooked the fuel line up, turned on the gas, the float bowl filled and that was it. No gas came pouring out as expected, the bowl didn't overfill... So I turned the cable assembly to simulate some throttle. The pumper squirted a fair amount of gas out and that was it. I wonder if the fuel I'm finding in the intake is just from the pumper and my problem is an electrical gremlin???
  13. Greg Bender

    Greg Bender Long timer

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    Spark plug cap?
  14. BigD_83

    BigD_83 Adventurer

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    Having read through the posts, this certainly makes me think it is a timing/weak spark issue rather than carburation. I've seen this happen with some of my other bikes, but not to the extent you are describing. In one case it was a bad coil, another was bad spark plug leads.

    There are plenty of cases of coils/CDIs/ignitors failing when hot, at least in the Suzuki GS and Honda CB world.

    I'm new to the DR game, but thought I'd throw my point of view out there. I hope I can learn something from this for when I finally pick up my DR 350/450 setup similarly to yours.
  15. Wadester

    Wadester Rides a dirty bike

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    Don't know if this would help diagnose your issue - but a trick I used to use back in automechanic days for finding a miss/bad spark wire/plug would be to use an inductive pickup timing light. It can tell you if and when you're getting spark, since the inductive pickup only "fires" if there is enough electricity flowing. That would show you if the spark was failing when it was running bad.
    Biggest problem is that you also have to pull the trigger on mine. If you have to be moving (under load) for it to happen, you'd have to secure the timing light and strap down the trigger (and the excess lead wires of the TL).
  16. RuggedExposure

    RuggedExposure Now with more rugged

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    ok, lets sum things up:

    Bike ran perfect for a few months.
    Adjusted the valves, put about ~700 miles on it, no problems.
    Installed Acerbis tank,
    Bike began popping from the exhaust.
    about an hour later it began sputtering and losing power.
    half an hour later it would barely run.

    Installed a new coil, bike ran a little better.
    Installed new plug, bike ran even a little better.

    After a few minutes of riding, it went back to having problems.

    Bike will fire up easy, idles fine, once you start riding around and giving it throttle it bogs down and dies. Plug will be fouled and fuel is in the intake (possibly from the pumper jet).

    Carb has been thoroughly cleaned and inspected, no leaks at all.

    I am now inspecting for an electrical problem. I checked the kill switch, seems to be no issues there.
    I even took off the security switch I installed next to the coil, no difference.
    I checked for spots where the wires could be rubbing, or loose connections. Flexing and bending the wiring to the CDI and stator made no difference in how the bike is running.

    Bike will idle now with the choke on, but barely idles with the choke off. Problem is now at its worst.

    CDI? Regulator? or Stator?
  17. RuggedExposure

    RuggedExposure Now with more rugged

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    Here is the stator:
    [​IMG]

    How can I tell if this is operating properly? Anyone see any problems?
  18. MrPulldown

    MrPulldown Long timer

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  19. RuggedExposure

    RuggedExposure Now with more rugged

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  20. Wadester

    Wadester Rides a dirty bike

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    In the cap at the plug:

    http://www.ngksparkplugs.com/products/performance/resistor_covers.asp

    [​IMG]

    Also - I always thought that resistors in spark systems were for noise reduction, but:

    http://www.ultralightnews.ca/articles/resistorcapsandplugs.htm

    "At a voltage of about 7KV the plug fires (irrespective of resistance). Until that happens NO CURRENT FLOWS. Whether you have resistance or not does not matter. A paltry 5KOhms does not do anything when compared to the nearly infinite resistance of the gap itself (until the plug fires that is). Once the plug fires the resistance comes into play. The coil cannot get rid of its energy in the shortest possible time due to the resistance.
    This reduces current flow in the spark and it takes quite a bit longer until the energy in the coil has expelled itself via resistor and spark gap. This results in a longer spark. However the spark is weaker due to energy loss in the resistor."