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CRF250X TPS calibration

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Hey does anyone know what the calibration window is (in OHMS) for the throttle position sensor on the CRF250X carb. Its a friends bike and I do not have the manual. Any help is appreciated, thanks!!!

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The standard reading is 4k-6k at 68f between the blue and black wires

adjustment gets a little more complicated, but you didn't ask for that.

If you think it's bad you can run with it unplugged, they run fine.

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Yes, I'm looking for what it should be adjusted to, thanks!!!

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you measure the total resistance which should be between 4 and 6k ohms.

and then once you find that number multiply it by .13 and .15 and that is the window the that the small reading should be in.

So if you have a reading of 5000 ohms... 5000 x .13 = 650 5000 x .15 = 750 so your windows is 650 -750 ohms of the small reading.

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A little more involved than I thought, I get it though, thanks for your help.

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The tps voltage signal can be used for whatever the designer of the ignition 3D map wants. A simple 2D map (graph) would have rpm and degrees of advance as the X and Y. With a tps you add a third (3D) side, Z.

With this you can vary the timing for the load on the motor, for example 5000rpms with the throttle wide open (high load) can be different than 5000rpms with the throttle 1/2 open (partial load). The high load situation has the cylinder being filled more which results in more compression, which require less timing advance. Partial throttle, less fil, less compression, more advance can be given. That's where tps more optimizes the ignition timing.

BUT! the optimization may not always be for performance, it also can be for tuning in emmsions levels, and also has been used for noise abatement, usually at test rpms.

SO, when your talking a an X type , green sticker, offroad type bike, or street bike. You Just don't know what the optimization was gear for? But you can simply run it disconnected and see if there is any benefit or downside, then decide. Another factor with this bike is the effect on the map when you unground the pink wire. For all we know it may take the tps factor right out? or change it? Stuff like this you just have to experiment.

If it runs fine unplugged ,what's the benifit of it at all??? Just curious, !

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doing the pink wire mod on the stock x cam, especially the california x cam, yields no results. BUT do the pink wire mod on the R cam and OH lordy it makes the bike wind out like a crack head high as hell. Its obvious that the pink wire mod changes ignition mapping over to the R map and produces a positive so long as you have the cam to go with it.

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