Yamaha WR250R Mega Thread

Discussion in 'Thumpers' started by Sock Monkey, Apr 7, 2008.

  1. OSU

    OSU Adventurer

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    im going to college for electrical engineering, its my job to make things overly complicated haha :lol3
  2. Sock Monkey

    Sock Monkey 99% bullshitter...the other 1% is just lies

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    LOL.

    FWIW, I was told this mod only changes the idle circuit (lower revs), and NOT the entire range. That may have been BS, but I erred on the side of caution (since I opened up the airbox and replaced the pipe) and ended up getting a FMF Power Programmer. YMMV, etc.

    -SM
  3. OSU

    OSU Adventurer

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    ill be checking my plug to see if it gets really black from running too lean and I think ill put temp a gauge on the case
  4. cug

    cug --

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    Quick question: what is the largest rear sprocket I can mount on a WR250X with the OEM chain? I googled and found it for DRZ and YZ models, but not for the WR250X.
  5. skierd

    skierd Wannabe Far-Rider

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    44, maybe 45T. Stock chain is 108L. You'll need 110L for a 46T rear.
  6. cug

    cug --

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    Thanks. Bummer. I see only 42 and 47 so far. Have to search a bit more. Not too big a deal as I'm not planning on really technical stuff, but was hoping to find a 43 to 45T that'll fit X hubs.
  7. skierd

    skierd Wannabe Far-Rider

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    Steel sprockets ok?

    Part number JTR2452.xx where XX is your tooth count for JT steel sprockets. For a 44T it would be JTR 2452.44. I'm running a 42T right now (JTR2452.42) and have used a 46 and 47 in the past.

    For reference the front sprocket is a JTF1590xx. JTF1590xxSC if you want the lightweight steel version with holes drilled in it, otherwise it'll be solid.

    Unsure of other brands, so far my sprockets outlast my chain as it is and they're cheap so I haven't had any incentive to switch.
  8. skierd

    skierd Wannabe Far-Rider

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    BT-003 RS Ordered, 140/70-17 rear and I'll burn up my take off OE BT090 front for this change. Sportbike Track Gear had them for $112, about $10 better than the next nearest site.


    I have a small to medium conniption every time I see or think about that luggage setup, I think I pack lighter for a month on the road... :rofl. Looks like the beverly hillbillies got themselves a motorsickle. :D

  9. SR1

    SR1 Back in S. Korea

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    Well, that's the danger of being 7 time zones ahead of you guys, I miss out on all the hot deals.

    I'm glad someone posted a link to that 4.7gal tank ad, because gol'dang that fucker is wide. Yup, happy with the direction I plan to go, but I still appreciate all the inputs.
  10. SkidMarx

    SkidMarx Long timer

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    That's backwards. White is lean, black is rich.
    I'm sure that was just a test to see if anyone was reading your posts.
  11. ArmyJoe

    ArmyJoe Long timer

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    Is it any wider than the stock shrouds that it replaces?
  12. ironbrewer

    ironbrewer Hopefully Riding

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    I use my GPS for a speedometer and odometer. Can you in fact put your WR into permanent CO diagnostic mode to have a tach all the time? Would you just permanently ground the wire? And if you did this would you have to go through the program every time you started up the bike??
  13. bhd1223

    bhd1223 Been here awhile

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    Just some info regarding the BT-003 and the BT-003RS. They are 2 different tires. Very different in fact. The 003 is a straight race tire. It's not designed to work well in the wet, racers use rain tires for that. The 003RS is a "racing/street" tire. It's designed to work for people commuting on their bikes and going to trackdays. I actually ran/run the 003RS on my EX500(Ninja 500) track bike. I say used because I didn't race or do any trackdays this year due to the WR consuming my track budget. For the events and trackdays I did on the 003RS I was very impressed. No experience with rain though. They stick well until you start really pushing them to borderline expert club racing level. They slide predictably from what other have told me, I've never pushed them to that point.

    YMMV.
  14. GotMojo?

    GotMojo? Long timer

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    ]

    Ya, I think most people (like me) in this thread are referring to their tires as the BT-003, but we actually have the racing/street version (BT-003RS). Is the racing BT003 even street legal?
  15. cug

    cug --

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    Awesome info! Many thanks, I'll find one now! Wheels are ordered, now all the other related hardware has to be decided (tires) and ordered (tubes, bands, ...). I'll use my existing rotors and whatever else I need for the time being so save some money as I need so many other things for this bike for my November trip.
  16. GSBS

    GSBS FunHog

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    I've had the MT-43 DOT Trials-type tire on my WR-R for just over 1,800 miles now and thought I'd post some photos to update how it's wearing. To my eye the center lugs are about halfway gone, but the tire still grips about the same as when it was new as far as I can tell.

    'Course, with all that gas a-sloshing around in my big-ass IMS tank, this could just be a byproduct of the worn, shorter knobs counteracting a jello-like effect caused by the longer knobs when they were new and gummy, but what do I know? :lol3

    I'm pretty much running 12 psi all the time in this tire based on advice from inmates here that running more on-road would accelerate wear in the center.

    Looks like this tire will have a longer "useable" life than the D606s I had been running. I'm thinking this one might see 3K miles before it needs replacing. The D606s were almost completely gone at 2,500 miles and were all but worthless off road long before that.

    Will update again as they wear out more...

    [​IMG]

    Closer view...

    [​IMG]
  17. bpg

    bpg Off Trail

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    That was one of many eye-opening experiences I had with the MT43 - when a knobby is half-worn, traction suffers quite a bit; when the 43 is half-worn, only mud traction seems to suffer. They'll still crawl their way up a slick rock face with less than 1/4" of "knob" remaining..:wink:

    I experience the same thing with regards to wear and PSI. It's very cool to be able to run the same pressure on and off road, no need to carry a pump for the transitions.

    That right there nails it. I'd personally rather have great traction most the time on the MT43, rather than good traction for a bit, then mediocre and always diminishing traction the rest of the time on knobbies.
  18. IdahoRenegade

    IdahoRenegade Long timer

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    ...and silver (aluminum) is way too lean!
  19. IdahoRenegade

    IdahoRenegade Long timer

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    I haven't tested leaving it grounded, but I think it just enables diag mode, you would still need to hold down S1 & rst while turing on the key to get into it. Still, it would be nice to have the option. I learned a fair amount just playing for a few minutes, as far as rpm (on the tach) vs how it sounded/felt. There's not much there below 6k...
  20. cug

    cug --

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    It will go back to normal whenever you turn off the bike. I have it permanently grounded (previous owner did that) and you have to go through the normal procedure.

    Also it doesn't turn on the odo in that mode. So no mileage recorded. Which is not what I want.