DR350 Thread

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

  1. psmcd

    psmcd Long timer

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    I typically ride with arches on the pegs, toe under the shifter when accelerating, over the shifter decelerating. I only place ball of foot on pegs when in a deep rut or large rocks. My racing days are long past but even then placement was slightly behind ball of foot.
  2. ghebinkim

    ghebinkim n00b

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    Oddometer:
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    Mountain View, CA

    Hey DR350 experts,

    Sorry to quote such an old post, but I've got a question for you all:

    I'm riding a '91 DR350S that has a 13/43 gearing. From what I understand, 14/43 is stock for this particular model. According to Gregory Bender's gearing calculator, I should be seeing 5700 rpm at 60 mph. However, I'm hitting an indicated 7k rpm at an indicated 50 mph. So... something is wrong or different!

    Has anyone had any trouble with their tach over-reporting or the speedo under-reporting? I know speedos generally have a large error, but not THIS large... The only other thing I can think of is that the clutch could be slipping at high speeds, but it feels pretty grabby when I accelerate. Could someone have changed out the gearing in the transmission itself? Ideas would be appreciated... Thanks!

    Kevin
  3. Greg Bender

    Greg Bender Long timer

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    Hi Kevin,

    To give credit where credit is due, that calculator is not mine (I just posted it on my website). Instead, it was created by Jim Randall.

    Sorry, I don't have much in the way of helpful input. The tach on my 1999 SE seems pretty close to what the calculator predicts.

    Regards,

    Gregory Bender
  4. Dark_flame221

    Dark_flame221 Adventurer

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    Oddometer:
    27

    cuted the ktm grip about half an inch, and cuted the end guard brace but, still not exactly like i want them since their is interference between clutch cable and the hand guard brace.

    Info : cycra hand guard with pro motion mounts, it's not a direct fit for a dr350se 98 :( or at least use some Tusk Handguard Adaptor instead should be way better
  5. psmcd

    psmcd Long timer

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    My tach was wack with a bad battery. Showing 9,000 at 60 with 15/43.
  6. ghebinkim

    ghebinkim n00b

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    Hmmm interesting, I'll have to check that out. I assume you're talking about the main battery... there's not a separate battery hidden in the instrument cluster?
  7. thump!

    thump! Adventurer

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    An almost identical mirror (to the Ken Sean) is available from EMGO. Local shops around here have them on the wall. Mail order from Dennis Kirk and others.
  8. MrPulldown

    MrPulldown Long timer

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    I broke the main batteries negative terminal. Seems common as I have repaired this on my friends DR350 as well. Looks ok but it is cracked and gives intermittent battery grounding connections.

    My tach too was wacked when this was happening. Very noticeable erratic swings in the tach needle. Only did this for a short ride before I figured it out and fixed it.
  9. Askor200

    Askor200 Adventurer

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    Maybe the tach/gearing calculator isnt working for your bike because the final drive ratios are different(?) between the early years and the later years(?) not too sure about that but it may be the problem
  10. thump!

    thump! Adventurer

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    The calculator deals with the primary drive ratio change that was made with the '94 model.
  11. aceofspades991

    aceofspades991 n00b

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    Sep 29, 2013
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    5
    Hi all,

    Are there any compatibility issues year to year with the bottom ends of the DR350? In other words, would I be able to take a case/transmission from an older bike and put it on my 99 DR350SE as long as the case came off an e-start bike?

    Thanks in advance for any replies.
  12. veriest1

    veriest1 Grand NOOBlet

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    Ok pumper carb is still giving me issues.

    It was running fine but still dieing at high rpm last week. Traced it back to my ghetto intake boot setup that came with the carb since it wasnt sealing. Called Jesse and problem solved with his "biscuit" and spacer.

    Got the carb in but now it won't start and when it does it dies if I touch the throttle. So...

    TM33 pumper
    137 pilot (or whatever comes in a new tm33)
    145 main 'cause I was chaing high rpm problems but it shouldnt effect starting)
    Fuel screw is 1.5 turns out.
    Idle air is just touching the pulley.

    Set like this it will start and idle 1/2 the time but that's all it'll do.

    Sent from my SAMSUNG-SGH-I727 using Tapatalk
  13. dav_dman

    dav_dman Been here awhile

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    no expert but sounds like you're not getting a transition to the higher speed circuit, which means the needle stuck in the seat, float stuck, or something in that part of the carb.
  14. MrPulldown

    MrPulldown Long timer

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    Pretty sure it will all bolt up. First gear got a little lower in 97 at 2.5 from 2.416.
  15. ghebinkim

    ghebinkim n00b

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    Thanks everyone, turns out my battery wasn't holding a charge after sitting in storage. A new battery fixed the tach issue and it reads out more reasonable values now!
  16. markk900

    markk900 Been here awhile

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    The calculator bases everything off of a reading of indicated speed and indicated rpm from the creator of the calculator (ie. 5300 rpm in 6th at 60mph on a specific brand of tire). Everything else is a % of that single reading, so there is a great deal of variability that could be had.

    Use it as an approximation only, though most readings should be reasonably close (ie +/- 500rpm).

    There also appears to be one insignificant error - while the calculator deals with the primary ratio change, at least in comparison to my 95 SE the first gear ratio in the 94+ column is wrong. According to my manual it didn't change from the earlier bikes.
  17. thump!

    thump! Adventurer

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    That's exactly how the calculator was developed. My bike, my instruments. It was intended as a predictive tool for the effect of sprocket changes.

    The tachometer, being electronic is probably the more accurate instrument and we all know the speedometer is several mph optimistic. However, IF the observed speed and rpm cells in the spreadsheet are adjusted for YOUR bike (the tire is the biggest variable), the calculator should be very accurate since the mathimatical relationship of the gears is fixed. Keep in mind the indicated speed on the DR350's mechanical speedometer may NOT match up at all speeds but that will be due to the limitations of the crude rotating magnet instrument.
  18. boboneleg

    boboneleg we can rebuild him.

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    That did the trick :clap

    As you can see there was a fair bit more wear on one side of the bearing compared with the other side.

    [​IMG]

    [​IMG]
  19. Greg Bender

    Greg Bender Long timer

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    Hi all,

    I've been finalizing the build of a 1993 DR350 with a 1991 engine (dirt model). The other day I noticed that the petcock was leaking externally. Rather than investigate a fix to the original, I decided to purchase a replacement petcock. A quick stroll through eBay found this unit:
    http://www.ebay.com/itm/190618007951?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

    At $12.50 delivered, it was certainly inexpensive enough. It arrived quickly and functions correctly (no leaks when closed, flows fuel when open).

    However, I do have one significant complaint: the barbed hose connection is ~6mm in diameter, whereas the OEM DR350 carburetor's hose connection is ~8mm. 1/4" fuel line is loose on the 6mm side (you'll have to use a clamp) and tight on the 8mm side. Liveable, certainly, but not optimal. I much prefer the OEM Yamaha Raptor petcock I purchased several years ago for ~$25.

    This may seem like a insignificant detail, but it is one that I find annoying. Liveable, certainly. But annoying.

    More on the superior Raptor petcock here:
    http://thisoldtractor.com/gtbender/dr350.htm#gtb_petcock_replacement

    Regards,

    Gregory Bender
  20. jules083

    jules083 Long timer

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    Found this one for sale locally. He said he'll take $500, I don't know. Seems high to me, I was thinking $250-$300. Any thoughts? He said it runs but needs a carb, has good title. Not sure of the year yet.

    [​IMG]

    Sent from my SAMSUNG-SGH-I747 using Tapatalk 2