ok guys so I got Rubi running and driving after replacing the entire harness, carb, petcock, cleaned gas tank, oil change, coolant flush. The bike is a 2002 rubicon 500, I put an 05 carb on it due to the awesome price I paid for it. The bike runs great at full throttle but 0-1/4 throttle it spits and sputters randomly. I decided to calibrate the TPS sensor before adjusting the mixture screw, well when I checked the sensor it was showing a erratic reading on my ohm meter so I checked the pins coming out of the sensor and they were loose. I then re soldered the pins on and now I get a much more consistent reading but it still seems to jump around some when I turn it with a screwdriver. I am wondering if all Tps sensors jump slightly when calibrating or if it is a steady reading. I don't have another one to compare to so here I am. I dont want to replace it if it's not necessary considering that sensor is $100. Thanks for the input
02 Rubicon 500 TPS
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Well, first of all the TP sensor is not interchangeable between the '02 and '05 Hondamatic electrical systems. You will require an '02 TP sensor, as they operate in a lower resistance range than the '04 & up TPs do. You may also need the matching '02 carb to make it work... dunno if they are otherwise identical or not, other than resistance range? Let us know more about what ya got and we might be able to help you set it up.
Have you got a copy of the service manual yet? You will need one for the TP initialization procedure and can find them in the manuals and schematics forum.
Have you got a copy of the service manual yet? You will need one for the TP initialization procedure and can find them in the manuals and schematics forum.
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Well the part# for both 05 and 02 throttle sensor show the same but in the catalog they list 2 options for the 05, so are you saying the part# 16061-HP0-A01 would be for the 05 and the part#37890-HN2-006 would be for the 02? not sure since i am just looking at an online catalog.
The bike caught fire under the carb due to birds building a nest under the carb, so thats why I had to change out the things listed above. Started on 2nd pull of the pull start after sitting for about 8 years. Haven't put a battery in it yet, could that be causing me issues?
Don't start the motor again until you put a good battery in it!! You'll fry stuff! And no, it won't run right without a good battery installed. What were you thinking?
I don't know about part number differences, just going by the TP resistance specs listed in each of the service manuals. That said, I would attempt to complete the re-initialization procedure using your '05 carb and TP (after you put a good battery in it! And after you adjust the throttle cable slack) and see if it works.
I don't know about part number differences, just going by the TP resistance specs listed in each of the service manuals. That said, I would attempt to complete the re-initialization procedure using your '05 carb and TP (after you put a good battery in it! And after you adjust the throttle cable slack) and see if it works.
I only have general knowledge of mechanics, sorry I don't know everything YOU do. Thats why I came here to ask. I had no idea it was bad to run it without the battery, I only knew it should run without it and that I have been working on this thing on and off for about a month so i was excited to see it run. I will get the battery and try your suggestion and post the results. Still doesn't explain why the sensor readings jump around, I would assume that is not normal
The sensor resistance jumping around indicates a bad sensor, as you suspect. Those TPs are sealed up though, so in case those erratic ohm measurements are being caused by your meter leads connections to the TP pins, I'd want to test the TP in normal working conditions on the carb before spending money on a new one. You may learn that the TP works fine after initialization and having a new battery installed...? Its worth a shot.
Once you get your new battery installed, check the DC charging voltage (across the battery terminals) while the motor is idling. It should rise to 13.5-14.5 volts DC as the battery recharges after using the starter motor to start it. Then put your meter on the AC volts range and check for any stray AC voltage reading across the battery terminals. There should be no more than 15-20 millivolts AC observed, else the regulator/rectifier is damaged.
Just some future FYI here... Running the motor without a good battery installed can fry the ECM, the CDI, and any low-voltage sensors on the bike. It can stress and overheat the regulator/rectifier as well, causing internal diodes to short (or open) and fail. If you run the motor with a badly sulphated/shorted battery in it the alternator stator windings can fry as well.
I'll be looking for your good news posts...
Once you get your new battery installed, check the DC charging voltage (across the battery terminals) while the motor is idling. It should rise to 13.5-14.5 volts DC as the battery recharges after using the starter motor to start it. Then put your meter on the AC volts range and check for any stray AC voltage reading across the battery terminals. There should be no more than 15-20 millivolts AC observed, else the regulator/rectifier is damaged.
Just some future FYI here... Running the motor without a good battery installed can fry the ECM, the CDI, and any low-voltage sensors on the bike. It can stress and overheat the regulator/rectifier as well, causing internal diodes to short (or open) and fail. If you run the motor with a badly sulphated/shorted battery in it the alternator stator windings can fry as well.
I'll be looking for your good news posts...
The sensor resistance jumping around indicates a bad sensor, as you suspect. Those TPs are sealed up though, so in case those erratic ohm measurements are being caused by your meter leads connections to the TP pins, I'd want to test the TP in normal working conditions on the carb before spending money on a new one. You may learn that the TP works fine after initialization and having a new battery installed...? Its worth a shot.
Once you get your new battery installed, check the DC charging voltage (across the battery terminals) while the motor is idling. It should rise to 13.5-14.5 volts DC as the battery recharges after using the starter motor to start it. Then put your meter on the AC volts range and check for any stray AC voltage reading across the battery terminals. There should be no more than 15-20 millivolts AC observed, else the regulator/rectifier is damaged.
Just some future FYI here... Running the motor without a good battery installed can fry the ECM, the CDI, and any low-voltage sensors on the bike. It can stress and overheat the regulator/rectifier as well, causing internal diodes to short (or open) and fail. If you run the motor with a badly sulphated/shorted battery in it the alternator stator windings can fry as well.
I'll be looking for your good news posts...
Thanks for the info you have been a big help and you learned me something as my pops would say. I will check all things noted and post the results. However I think I need to go ahead and invest in a new sensor considering the back casing on it was in the bottom of the box when I got the carb in the mail and I glued it back on just to see what happened. Thanks again
Ok so I got the new TP sensor and a new battery, I set the TP sensor ohms at .500 and it was smooth and easy to set like I was expecting. I did the initiation procedure for the TP sensor and it runs great. However now I am running into a vapor lock problem I think. It runs great for a while then it runs out of fuel as if there is a blockage in the line. The petcock, carb, and line are brand new also I can see that there is not anything blocking the petcock screen inside the tank. When it does this taking the fuel cap off doesn't help at all but if I squeeze the fuel line repeatedly it will start flowing again. Not a huge problem as we dont ride very far usually but I would love some help on this issue. Thanks guys
Well, if it is starving for fuel ya obviously gotta clean them all more thoroughly. Or did you put a cheap china carb kit in it...? If so, ya gotta put the OEM parts back in it and set the carb up exactly as the service manual says. Just in case, don't put any ethanol fuel in it either. It rots very fast.
Well I have discovered that the fuel is boiling in the line right where it gets closest to the top of the engine as it goes down to the carb. So I wrapped my fuel line in a bigger hose with heat tape around it and it helped but it seems to need more of a heat barrier so I'm not sure if I am missing a piece as it was burnt up when I got it and have never owned one.
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