Switch for TPS

Went for a ride the other day, It sure felt good to get out. Like I said in a earlier post small difference in performance and much less surging. To switch the TPS off you also have to shut the Engine off to reset the CDI.

I installed spdp switch for now, still cant figure how to have the return voltage back to the CDI work with that switch. It is to cold outside to do any testing. William1 let me know if you come up with any ideas.

LOL, I've been letting you d the leg work.... :p

Went for a ride the other day, It sure felt good to get out. Like I said in a earlier post small difference in performance and much less surging. To switch the TPS off you also have to shut the Engine off to reset the CDI.

So you've found you need to shut the bike off to 'switch modes' with the TPS? If you flip the switch while riding, what happens? Certainly there must be some effect as the variable voltage has gone away. Have you found you must be in CDI 'limp mode' to make this useful?

You mean to say the snow, the housework, the chores, and finding the switch are just excuses for me to do all the legwork, your a funny guy :p William. I guess I was having to much fun:ride: to do much testing but once the weather gets better again I will try again,

Oh I almost forgot WE need to figure out how to wire the switch to still get voltage back to the CDI when the TPS is turned off, I think it is necessary Will we have to use a second switch or some other kind of switch.:p

Nah, my excuses are valid. I just figured you seemed more motivated than I and appeared to be thinking this through much more throughly than me so I did not want to get in your way. But seriously, I cannot find the switch. I'm going to have to buy one I guess.

Let me see if I can help. You want the full power to go through a resistor (about 6 K ohm) from the yellow lead to go the blue wire and at the same time, taking the TPS pot out of the loop, right? This will tell the engine the throttle is at WOT. To do this, you'll have to have either a double pole, double throw switch or relay. One side disconnects the blue wire from the TPS, the other connects the blue to the yellow with the resistor in line.

Is this what you wanted to do? If a DPDT switch cannot be sourced, the bar switch could energize a relay and the relay could easily do the disconnect/jump with the resistor. You want to do it on this side as if the system had a problem, you'd want it to be in in regular 'WR' mode plus the fact that 99%, you'd be in this mode anyways.

I Forgot about using a Relay that will work. We have such a vast area of riding here sometimes we have to travell a 100 miles or more to get to the next road or trail and I dont like the surging its very annoying. Thanks William

See, even though I have not actually touched the TPS on my bike yet, I was able to help.

I have now gone seven days since my last cigarette (Export A Green).

Cruising along 50-60 mpg :lol: no stutter,jerking,hunting or surging, mes very happy:banana: :p:lol::cry:

Cruising along 50-60 mpg :lol: no stutter,jerking,hunting or surging, mes very happy:banana: :p:lol::cry:

Is it switched or un-plugged?

It is switched :p

It is switched :p

So I've been following this thread but can't tell if you have shorted the voltage back to the CDI or not?

If not, is it "switch on the fly" or do you need to shut the bike off for a successful switch as mentioned above?

Thanks Dok :lol:

I still have not completed the switching to allow the voltage to return to the CDI, But that is the theory. When the switch is in off position the voltage will return to the CDI and hopefully it will allow for switching on the fly. Not that this is relevant but I installed soft foam in my seat to save my ass. ( what a difference ) Guts Racing. :p

I still have not completed the switching to allow the voltage to return to the CDI, But that is the theory. When the switch is in off position the voltage will return to the CDI and hopefully it will allow for switching on the fly. Not that this is relevant but I installed soft foam in my seat to save my ass. ( what a difference ) Guts Racing. :p

I've had a soft GUTS seat for years and love it:thumbsup:

OK so it's 1. shutdown 2. switch 3. ride.... I think I can handle that for now.

Thanks Dok.

Well William1 How are you making out with your switch, Did you find one that will work for you. Just about all the snow is gone around the house but we had a few flurries the other day WINTER just wont let go.

No, not lifted a finger. But.... my other bike a 470 DRZ SM just lunched the engine so I have been putting my spare time into swapping the blown engine for another I had. Just finished the tear down to determine the extenet of the major damage.

I am going to have to buy a switch. I will take apart a couple on bikes I have hear to see what the contact choices are to determine what one I should get.

My 2006 doesn't sputter at all, only en Neutral holding the throttle a little open. In the trail or road never....

I would like to retract my statement about holding the throttle steady, that was a bad example. I am also curious about the 470 too, would you let me know what you find.

A bit off topic but... Appears to be detonation, caused the piston to kant in the barrel, blowing out the skirt and shattering the barrel. A full tear down, cleaning, new barrel and valve inspection is all it should need. Will lower the compression slightly on the next build and not ride the same way (was about two hours of slow, chuggy, hot riding, not what a SM is designed for.)

Not hat anyone cares but I just complete step one. This was a measuring of voltages at the TPS to get values to duplicate when the TPS is disabled but emulated to retain most of the performance

Throttle Black Blue/Black

Idle .62v -4.2v

1/4 1.16v -3.71v

1/2 1.95v -2.98v

3/4 2.78v -2.27v

WOT 3.51v -1.32v

The other connection used was the Yellow. I am hoping I only have to be concerned with the Yellow and Black wire. It will make switching and total amount of wiring simpler.

My first series of tests will be riding the bike and confirming where exactly on the throttle the issue occurs. Then I'll select resistor to emulate the TPS at a slightly wider throttle opening and retest with the emulator. The goal being to have a the CDI provide enough ignition advance to make the bike perform but not so much to induce detonation. I plan to use slightly aged 91 octane fuel (3 weeks old) to make the test as real world as possible. I expect performance at idle and just off of idle to be poor and I think that will be an acceptable trade off. Anyways, this mod should be switchable on the fly and only needed when cruising so having to hit a switch for 20 miles of easy smooth riding is worth it.

Stock ride testing is done. TPS stutter mostly occurs at about 1/3 throttle. So I am now going to figure out what resistors to use to provide a TPS signal of about 2.8 volts. This will emulate the throttler being at about 3/4's, which is sort of what I was hoping for. This will need about a 3.5 K-ohm resistor. For the Blue/black wire, I'll need a 2.25 K-ohm if it turns out I need one there too. LOL, I just checked, none of either in stock here so off to Radio Shack I go...:worthy:

OK, I am back from Radio Hack. Total outlay there was $6.00 I got 5) 3.3K and 5) 2.2K resistors. I also got a triple throw, double pole switch. Not water or vibration proof, but good enough for testing. It will enable me to test and run the engine in three distinct states. Stock, TPS engaged, TPS disconnected and the third will be with the resistors in a circuit to emulate the carb being at about 3/4 throttle. If the testing produces viable results, I'll work on a better switch and mount. For testing, I will just make a small bracket and have it on the side of the radiator shroud. I also already had in stock, some of the water/dust proof OEM style three pin connector. These were purchased from Electrosport (Part# ES143) a while back. What I am going to do is make a little harness to plug in between the TPS and the OEM harness. Nice, simple and noninvasive. I'll wire it up today and test tomorrow, maybe.

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