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TPS & Solenoid? HELP

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Hey guys I had a pwm will be upgrading to pwk air striker 38 for my 99 yz250

My old carb only had the solenoid connection (red) Throttle Position Sensor (yellow) want on it

My two questions are what are those for?

&

Will there be a problem from me going to only having the solenoid connection to not having none at all on JD pwk 38 ?

Please help me understand thank you who helps .

IMG_1145.PNG

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I have just done this exact same thing. I bought a pwk 38 off a 2004 yz250 and have just finished the conversion to make it work without the electrics on my 98 wr250z basically same as your bike but has lights. It's not too hard to do. So what I did was pull out the solenoid and find a 8 mill bolt with the matching thread. I then cut off enough to give me a decent amount of bolt in the hole. I cut a grove so I could use a flat screwdriver to screw it in and used blue loctite to seal it. Under that is the little jet labelled 1 in the top pick of your post. I found a small bolt that matched that and did the same. Some use a grub screw. I just sealed it with the loctite again. The TPS in yellow in your picture you can just leave but I found that it fouled on the frame. This stops the carb from sitting in the intake boot properly. So I took it out and got rid of the black sensor. I cut out the shape and mounting holes from 3mm aluminum plate. I lapped it flat and used blue loctite again to seal it. I have not tested the carb and jetting yet as the carb bowl seal is stuffed and it was leaking fuel everywhere. Just waiting on the seal from the dealer. Good luck. 

I have just done this exact same thing. I bought a pwk 38 off a 2004 yz250 and have just finished the conversion to make it work without the electrics on my 98 wr250z basically same as your bike but has lights. It's not too hard to do. So what I did was pull out the solenoid and find a 8 mill bolt with the matching thread. I then cut off enough to give me a decent amount of bolt in the hole. I cut a grove so I could use a flat screwdriver to screw it in and used blue loctite to seal it. Under that is the little jet labelled 1 in the top pick of your post. I found a small bolt that matched that and did the same. Some use a grub screw. I just sealed it with the loctite again. The TPS in yellow in your picture you can just leave but I found that it fouled on the frame. This stops the carb from sitting in the intake boot properly. So I took it out and got rid of the black sensor. I cut out the shape and mounting holes from 3mm aluminum plate. I lapped it flat and used blue loctite again to seal it. I have not tested the carb and jetting yet as the carb bowl seal is stuffed and it was leaking fuel everywhere. Just waiting on the seal from the dealer. Good luck. 

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I have just done this exact same thing. I bought a pwk 38 off a 2004 yz250 and have just finished the conversion to make it work without the electrics on my 98 wr250z basically same as your bike but has lights. It's not too hard to do. So what I did was pull out the solenoid and find a 8 mill bolt with the matching thread. I then cut off enough to give me a decent amount of bolt in the hole. I cut a grove so I could use a flat screwdriver to screw it in and used blue loctite to seal it. Under that is the little jet labelled 1 in the top pick of your post. I found a small bolt that matched that and did the same. Some use a grub screw. I just sealed it with the loctite again. The TPS in yellow in your picture you can just leave but I found that it fouled on the frame. This stops the carb from sitting in the intake boot properly. So I took it out and got rid of the black sensor. I cut out the shape and mounting holes from 3mm aluminum plate. I lapped it flat and used blue loctite again to seal it. I have not tested the carb and jetting yet as the carb bowl seal is stuffed and it was leaking fuel everywhere. Just waiting on the seal from the dealer. Good luck. 
I have just done this exact same thing. I bought a pwk 38 off a 2004 yz250 and have just finished the conversion to make it work without the electrics on my 98 wr250z basically same as your bike but has lights. It's not too hard to do. So what I did was pull out the solenoid and find a 8 mill bolt with the matching thread. I then cut off enough to give me a decent amount of bolt in the hole. I cut a grove so I could use a flat screwdriver to screw it in and used blue loctite to seal it. Under that is the little jet labelled 1 in the top pick of your post. I found a small bolt that matched that and did the same. Some use a grub screw. I just sealed it with the loctite again. The TPS in yellow in your picture you can just leave but I found that it fouled on the frame. This stops the carb from sitting in the intake boot properly. So I took it out and got rid of the black sensor. I cut out the shape and mounting holes from 3mm aluminum plate. I lapped it flat and used blue loctite again to seal it. I have not tested the carb and jetting yet as the carb bowl seal is stuffed and it was leaking fuel everywhere. Just waiting on the seal from the dealer. Good luck. 

So basically just plugged the solenoid with a screw and the #1 on a picture with a screw aswell ? & Shouldn't is jetting carbs should already have this done ?

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I believe the solenoid only triggers at 8400 RPMs to shut that circuit off to lean it out for over rev. Why not just leave it unplugged? Granted the #50 power jet is a lot of fuel so maybe just throw in a #40 and leave the solenoid unplugged.??

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I believe the solenoid only triggers at 8400 RPMs to shut that circuit off to lean it out for over rev. Why not just leave it unplugged? Granted the #50 power jet is a lot of fuel so maybe just throw in a #40 and leave the solenoid unplugged.??

Okay I'm a just try that I just purchased a new jd pwk 38 W kit so I'll see how that will work out

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Kinger317 So do you think I should not have blocked that jet off?

Possibly, the OP was talking about a 99 YZ250 and I know that on the late-model bikes if you unplug everything going to the carburetor most people could not tell any difference. Not sure about your project but that carburetor was designed with that power jet circuit. The solenoid just shuts it off at 8400 RPMs for over rev...who cares? Most people would never notice if it was unplugged. Same with the throttle positioning sensor, if it doesn't have anything to talk to… who cares! Most people would never notice if it was unplugged anyway, the newer bikes CDI just goes into a separate default mapping when it doesn't see it I believe. If it was me, I would throw a 40 power jet in it put it in the bike with everything unplugged and try it. You will probably end up going leaner on the other jets as well given it's going in the WR. There's a lot of people around here who have a lot more experience with swapping and conversions than I do, maybe this will spark some other comments. Good luck

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