Where are your XT250's...let's see them.

Discussion in 'Thumpers' started by MEDIC-0372, Nov 4, 2008.

  1. mnuttall87

    mnuttall87 Been here awhile

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    He has been posting it up piece by piece on that Facebook group.
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  2. millman84

    millman84 Been here awhile

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    I have recently found out that Dynojet has discontinued their fuel controller for the XT250. I am going to see if procycle has one in stock but if not does anyone know if there is any other fuel controller options? I do have a resistor in the AIT sensor wire but I am now looking for something with better control.
  3. Unclviny

    Unclviny Been here awhile

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    It's called a Fuel Commander, I forget who makes it though. OOPS, that is the Dynojet one
  4. Bobbyh83

    Bobbyh83 Adventurer

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    What does the resistor in the sensor wire do? Anyone have a link to a write up?


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  5. twinrider

    twinrider Pass the catnip

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    Why bother trying to get more power out of this motor, put the money into suspension. :thumb
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  6. RL Lemke

    RL Lemke Long timer Supporter

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    Often times people will install something to "adjust" the temperature the sensor sends to the computer to enrich the fuel mixture. Often done when an owner feels that the engine is set to run too lean.

    Other times owners add more complicated and expensive sensor adjusters to enrich the fuel mixture across the RPM range in order to produce a little bit more power at the expense of fuel efficiency.

    I find it humorous when people put a lot of effort and money into forcing more power out of an engine, when a more prudent decision would be to purchase a motorcycle with the power they desire. Motorcycle ownership isn't a lifelong obligation, a we can switch between motorcycles at will. The little XT250 is not now, nor ever will be, considered powerful. Not the point of the little bike. It is intended to be a fun, reliable and quiet toy. Yamaha never intended it to compete with any KTM.

    Can the XT250 be enhanced so as to be a much better fun, reliable and quiet toy? Darn right it can.

    Can the XT250 be enhanced to compete with modern real-dirt-bike 250s? No way. Better to sell and get a RDB.

    How many XT250s have you seen compete in a Red Bull event?
  7. Bobbyh83

    Bobbyh83 Adventurer

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    I bought the bike knowing exactly what it is, which is exactly what I want at the moment. If given a choice, I tune a little rich which is why I was asking. I don’t care to go beyond that. I also like to tinker, I’m sure the engine is happy where it is.


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  8. RL Lemke

    RL Lemke Long timer Supporter

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    The simple temperature sensor in-line adjuster will enrich the fuel mixture a bit. Maybe what you desire. People on the BMW forums report that this does reduce the fuel mileage somewhat.

    If the headers glowed red when operating at lower RPM and slow speeds, some sort of enrichment would be helpful. Otherwise, not so much. Yamaha knows how to build and fuel all sorts of engines very well.

    I had a KTM 640 LC4 that was jetted too lean from the factory and the header did indeed glow when operated slow on the technical trails, or even idling. Enriching the carb with a jet change fixed that. No Mo Glow
  9. millman84

    millman84 Been here awhile

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    It is not the destination but the journey. I like to tinker with motors and see what I can get out of them. Unlike most people that get something large and american and throw more money at it I like to get something small and throw money at it.

    I did find another fuel controller for the XT250 but it is out of japan (that means instructions in Japanese) and a lot more expense.
    https://japan.webike.net/products/21292816.html

    Other options would be something arduino based and home made. I don't know if I am that good.
  10. RL Lemke

    RL Lemke Long timer Supporter

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    I hope you find that which you are seeking.

    My riding season starts in a month and I'm preparing my XT250 for the Moab Slickrock trails: Renazco seat, Cogent Dynamics suspension and sticky tires.

    We each find our bliss in so many different ways.
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  11. RL Lemke

    RL Lemke Long timer Supporter

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    Thinking more about engine performance, I wonder to what degree engine performance is affected by fully seated rings and completely free ring lands?

    In other words, can the Yamaha designed performance characteristics be met with poorly seated rings, which results in coked lands and the resulting blow-by?
  12. mnuttall87

    mnuttall87 Been here awhile

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    What tires are you running? Have you tried the IRC TR8 / Dunlop D606 combo? I haven't found anything that comes close to biting as hard as that setup does with this bike.
  13. mnuttall87

    mnuttall87 Been here awhile

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    @ben2go - I see you are tagged as Upstate SC. Where do you usually ride at? I've ridden Carolina Adventure World on the XT250, their trails are nice but the place is way too pricey. I'm in Charlotte NC.
  14. twinrider

    twinrider Pass the catnip

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    In the case of the XT250, throwing money at the suspension will make it faster than throwing money at the engine. At least offroad...
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  15. millman84

    millman84 Been here awhile

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    The motor in the XT250 also gets used in the 250 raptor and some of those do get setup for racing, there is more to be had out of that motor than you might think.

    As for faster, learning to ride this thing better would make a bigger difference than motor or suspension upgrades and that is probably what I need to be doing.
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  16. ben2go

    ben2go Long timer

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    I live in northern Spartanburg County about 15 minutes from Polk County NC. I ride the forest service roads around the Blue Ridge Parkway between Price Lake and Cherokee. I occasionally ride the FS roads around the GA/TN/NC area. The main area I ride is the FS roads around the hwy276 and BRP area.
  17. RL Lemke

    RL Lemke Long timer Supporter

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    Funny how I have photo examples of where I ride and have ridden.
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  18. ben2go

    ben2go Long timer

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    I have ridden all of those roads. I despise Tail of the Dragon. To many dangerous people trying to race around there. It used to be a fun road until the internet.
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  19. RL Lemke

    RL Lemke Long timer Supporter

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    The Dragon is just fine before 8:30 AM.

    When we ride, each days start is 7 AM.

    Frankly, I have countless fun roads in California that are empty. Roads so twisty that you beg for a straight section to recover.
  20. Cyclepath

    Cyclepath Lost wanderer

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    Yup ! :-)