WR250R Data, Specs and How-to's

Discussion in 'Thumpers' started by MoBill, Jan 2, 2010.

  1. mo_rider

    mo_rider the dude abides Supporter

    Joined:
    Nov 29, 2016
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    After being a bit frustrated with the "snatch" of the throttle on my WR250R, I did some research and decided to give adjusting the TPS a go. Below is a video I made showing how I adjusted the TPS using a low-profile ratcheting bit wrench I found on Amazon with a cut-down t-25 torx bit. Hope someone finds it helpful.

    Video:
    Low-profile ratcheting bit wrench: https://www.amazon.com/Neiko-03044A-Ratcheting-Screwdriver-Close-Quarters/dp/B000XYOUS6/

    After going from 15 to 19/20, the throttle snatch is a bit better at low speed and the engine braking doesn't seem as exaggerated as it was before. I'm happy with the results but will probably be looking to a fuel programmer in the future to see if it helps any.
    #81
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  2. eakins

    eakins Butler Maps

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  3. advmgm

    advmgm Long timer

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    Omaha Arkansas - Motorcycling Paradise
    G2 throttle tamer works miracles on the WRR.

    Sent from my SAMSUNG-SM-T377A using Tapatalk
    #83
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  4. mo_rider

    mo_rider the dude abides Supporter

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    Cool. I may have to purchase one to try it out. While I believe the TPS adjustment helped some, I'm still not happy with the initial on/off of the throttle. I've largely gotten used to it though so it's become less of a priority for me.
    #84
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  5. mo_rider

    mo_rider the dude abides Supporter

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    Well I got one. It's probably made a 50% difference in the snatch getting on the throttle and allows more to provide very little throttle to maintain a low speed, something I couldn't do before. It has not, however, improved the engine braking much. Not sure what could other than maybe a new programmer.

    All in all, a worthy upgrade.
    #85
  6. Chickenmunga

    Chickenmunga Been here awhile

    Joined:
    Jul 14, 2014
    Oddometer:
    284
    Location:
    Hillsboro, Oregon
    I've done the TPS, which did nothing noticeable
    I've done the G2 throttle tube, which was marginal
    I switched to 14/52 sprockets on a 130/90/18 D606 (which would be a 13/47 on a factory tire, if I recall?). I just finished that up tonight, took a first ride, and that really tamed it up. I'm not sure if it's a combo of the gearing and G2, or if the gearing would have done it by itself. However, there's a lot more smoothness on shifts. I can still get some snappiness on dumping the throttle, but nothing like before.
    The bike seemed happy enough up at 75mph, with some bit of pep to keep going.

    20180430_213948.jpg
    #86
  7. Chickenmunga

    Chickenmunga Been here awhile

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    Jul 14, 2014
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    Hillsboro, Oregon
    Yes, all stock engine parts, no tuners. I did a bit more commuting around Wednesday, and there's still some chop in 1st, but I feel I have to be more deliberate about it. Possibly because I have to move that big amount of extra mass back there on the rear tire (43T to 52T is certainly a size change)
    Not really sure I'm keen on disassembling the spark arrestor since I don't want legal ramifications. From the brief info I've read, removing that part is leaning out the bike, so maybe you are decreasing the throttle response enough to make a difference, but I'd be surprised since the people who take it off completely aren't reporting any perceived changes other than noise... maybe butt dyno is compensating any throttle difference.
    #87
  8. Traveller128

    Traveller128 Long timer

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    SW Idaho
    I've run both aftermarket mufflers and my modified stock muffler, and the power is actually slightly better with the modified stocker. Noisier with the aftermarket by a bit. Big difference was taking out the stock spark arrestor and changing the pipe in it to a bit larger pipe, duplicating the bell end in the muffler side of the pipe, but moving it away from the end cap of the spark arrestor so that it could actually move some air through it unlike the stocker. Only went from 86 dB to 88-89 dB, but made quite a difference in power. I put it back on last fall after experimenting with a Tusk muffler setup I built. The Tusk didn't feel like it made any more power, was just noisier going down the road. The modified stocker is probably what I'll keep. Mine is a 280cc upgraded bike with an AFR+ for tuning.

    Mind you, the modified muffler picked up quite a bit of power over stock along with cutting a 3 X 3 hole in the top of the airbox and mounting Frogzkin over it. Keeps the water out, lets it breath a bit on both ends.

    I have both the G2 tamer and tweaked the TPS to 19, and it's still not perfect, but it's vastly improved at low speed. Gearing it down makes it worse, gearing it up makes it less snatchy. I'm geared at 13/48 and with the big bore I'm thinking of going back to 13/46 or 47.
    #88
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  9. Two Moto Kiwis

    Two Moto Kiwis Homeless Somewhere

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    Location:
    Wanaka, New Zealand, ....What Trip!!!
    Heya Traveller128, I have just bought a WR250R for my travel, really only looking to remove the AIS and decat to take heat out of the factory muffler so I don't burn luggage straps.

    Interested to know if you believe any fuel adjustmets need to be done leaving the rest as is, all my knowledge and reading says it should be ok but I don't have my bike as yet so not rider time on it, would prefer not to have annything else module wise because this is a travel bike thus will be out in the styx and simplicity works better IMO.

    Thansk Andi
    #89
  10. BygDaddee

    BygDaddee Long timer

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    Bris
    How did you go with this, did you add fuel, change anything else ?

    #90
  11. Cuttlefish

    Cuttlefish Riding to disappear.

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    Location:
    Sunshine coast Qld Australia
    My Booster plug just left Brisbane "forwarded for delivery". It will be interesting to see if it makes an appreciable difference. Probably won't see it until Monday. AIS and flapper mods tomorrow morning. One more exploratory into Glasshouse on Sunday.
    #91