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tps adjustment

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Does anyone know how to adjust the tps, and what is the diffence between the hi and low range. My bike has always been hard to start hot, after a stall. And the valves are adjusted prefect! Can the tps cause a lean or rich setting!

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My bike has always been hard to start hot, after a stall.

Welcome to the 4t era.:):banghead:

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My bike fires up first kick when hot with the hot start. :)

To answer your question, the TPS controls the 3D mapping of the ignition. It does not adjust fuel/air mixture like the FI bikes.

Sometimes you just have to find what works with your bike when starting it hot. Some people have to give the throttle a quick flick, some pull the hot start, some just kick it over without either. Its all just figuring out what works for your bike.

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To see if the TPS is the source of your proble, unplug it from the harness and try to start the bike.

Hard to start hot (are you using the hot start on the carb?) may be due to the wrong pilot jet, improper fuel screw setting, too high a float level, leaking float needle seat among other potential causes.

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Bike has always been hard to start,don't know how come! Yes the hot start is used,sometime it takes 1 kick sometimes 50. I understand that the tps does not adjust the air/fuel mixture, I had read that it can cause the mixture to act like it is rich or lean? Does it advance or retard the ignition.

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Depends if the trans is in neutral or the blue wire is disconnected and if it is a WR or YZ. Generally, the TPS advances timing with a larger throttle opening and higher RPMs. If either of these are low, the timing usually is retarded.

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It's a yz-250f 2004, motor not stock 290 kit #2 cams intake and exhaust, eric gorr head work,and valves, pro curcuit pipe, jd jetting kit, it runs very well, but if you stall it your done! Love the bike better than a 450, But the starting is going to make me buy a ktm with electric start. Any idea if the starter jet has anything to do with this. It has been a pain in the ass to start since new.

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