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Adjusting TPS to 0.65

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Hello, sorry if this is a repeat question, I did some searching but didn't come up with much. Are most guys buying that adapter to set there TPS? Or is there a free way. I know you could probably just stab the wires but that doesn't sound to good. thanks!

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You can do it with a multi meter. Look on you tube.

Edited by 1 lunger

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It moves the throttle opening up (what the ECU sees) which also changes the timing. Some are concern that you can "run out" of timing on top end causing motor damage. There hasn't been any real proof of that. TPS tool for $25-35 is worth it and is easy to use. If you stab the wires you break the plastic coating and the copper wire will corrode, could cause issues year later.

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This is all food for thought , moves the TP over to the ECU brain view of more open throttle- adds predetermined fuel amount for a more open throttle position than it is really positioned at (richens as far as we know).

But it may also move certain lean spots (for emissions tests at set RPM tests) over as well, does anyone know the true factory ECU map graph? Food for thought emissions testing is done at specified RPM----logic tells me that the OEM will create a map to lean and retard timing at that RPM to burn the fuel longer and spraying less fuel at the spot on the map graph. TPS adjust may simply move that spot over to a higher RPM from 4k to 5k for example(??)

Next issue adding the advance curve earlier, so the ECU advances the ignition at lower RPM (or does it receive a direct separate actual RPM pickup from the engine???) I have been under the assumption that the TPS is the input for the ECU to manage both fuel injection and ignition timing (again food for discussion).

So if the TPS adds advance at earlier RPM (how many degrees???), say a few degrees of ignition advance at lower RPM it stresses the bottom end more along with other too much advance engine issues. Me personally if I was back on a FI fourstroke would never move the TPS, it is what/where it is factory set. I would for sure burn new maps and if the ECU is coded/locked I would go with a piggyback system like PC5, Bazzaz, JD or other to make Fuel adjustments but what do I know...I now ride a 2 stroke with a Keihin carb.

My 2 ex 310 Huskys were FI blackhead had an OEM TXC(race kit) ECU and ran super well, got me a bunch of ammie trophies, my redhead TXC310R was remapped in a good solid race map ran great, never touched the TPS on either machine. I figured I'd check in on this for fun and discussion.

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This is all food for thought , moves the TP over to the ECU brain view of more open throttle- adds predetermined fuel amount for a more open throttle position than it is really positioned at (richens as far as we know).

But it may also move certain lean spots (for emissions tests at set RPM tests) over as well, does anyone know the true factory ECU map graph? Food for thought emissions testing is done at specified RPM----logic tells me that the OEM will create a map to lean and retard timing at that RPM to burn the fuel longer and spraying less fuel at the spot on the map graph. TPS adjust may simply move that spot over to a higher RPM from 4k to 5k for example(??)

Next issue adding the advance curve earlier, so the ECU advances the ignition at lower RPM (or does it receive a direct separate actual RPM pickup from the engine???) I have been under the assumption that the TPS is the input for the ECU to manage both fuel injection and ignition timing (again food for discussion).

So if the TPS adds advance at earlier RPM (how many degrees???), say a few degrees of ignition advance at lower RPM it stresses the bottom end more along with other too much advance engine issues. Me personally if I was back on a FI fourstroke would never move the TPS, it is what/where it is factory set. I would for sure burn new maps and if the ECU is coded/locked I would go with a piggyback system like PC5, Bazzaz, JD or other to make Fuel adjustments but what do I know...I now ride a 2 stroke with a Keihin carb.

My 2 ex 310 Huskys were FI blackhead had an OEM TXC(race kit) ECU and ran super well, got me a bunch of ammie trophies, my redhead TXC310R was remapped in a good solid race map ran great, never touched the TPS on either machine. I figured I'd check in on this for fun and discussion.

+1 however I know several EXC owners that have adjusted their TPS without any issues. These EXC motors are among the leanest out there. No dead spots in the mapping or knocking can be heard in any RPM range. Again no prof raising the TPS voltage results in motor damage while keeping a realistic settings. After a certain volt no change can be felt and thus no more voltage is needed.

 

Your red head Husqvarna's did not respond to TPS adjustment like these newer KTM based bikes. No apples to apples anymore.

 

OP - It's your bike do as you want but when flame outs and jerky low throttle happens you will be seeing a dealer or adding $500+ in tuners. Don't get me wrong tuners are great if you want to add/mod items to your bike. Even stock a tuner will bring out more performance but at a cost well above a TPS tool and not needed/wanted for most owners.

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+1 however I know several EXC owners that have adjusted their TPS without any issues. These EXC motors are among the leanest out there. No dead spots in the mapping or knocking can be heard in any RPM range. Again no prof raising the TPS voltage results in motor damage while keeping a realistic settings. After a certain volt no change can be felt and thus no more voltage is needed.

Your red head Husqvarna's did not respond to TPS adjustment like these newer KTM based bikes. No apples to apples anymore.

OP - It's your bike do as you want but when flame outs and jerky low throttle happens you will be seeing a dealer or adding $500+ in tuners. Don't get me wrong tuners are great if you want to add/mod items to your bike. Even stock a tuner will bring out more performance but at a cost well above a TPS tool and not needed/wanted for most owners.

thanks for the info man, well sounds like more people are doing it than not, so I think I will. I appreciate all the info fellas

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Something to consider, a change from 0,61 to 0,65 is barely a movement on the tps. Actually, its almost difficult to move it that little when adjusting. Its probably around a 1-2% increase of throttle position reading.

This cant be changing ignition advance etc alot.

And it has to be supplying more fuel at any throttle positions! Rpm's wont climb at given X throttle position, as the throttlebody opening is as before. But more fuel will be supplied as the EFI thinks the throttlebody is letting in more air, and lean spots will be less lean no matter what.

Its a well tuned motor for sure, but still has head room for less quality fuel etc, so 1-2 dg ignition advance should be problem free.

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Something to consider, a change from 0,61 to 0,65 is barely a movement on the tps. Actually, its almost difficult to move it that little when adjusting. Its probably around a 1-2% increase of throttle position reading.

This cant be changing ignition advance etc alot.

And it has to be supplying more fuel at any throttle positions! Rpm's wont climb at given X throttle position, as the throttlebody opening is as before. But more fuel will be supplied as the EFI thinks the throttlebody is letting in more air, and lean spots will be less lean no matter what.

Its a well tuned motor for sure, but still has head room for less quality fuel etc, so 1-2 dg ignition advance should be problem free.

yeah that's a good point as well. Thank you

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Something to consider, a change from 0,61 to 0,65 is barely a movement on the tps. Actually, its almost difficult to move it that little when adjusting. Its probably around a 1-2% increase of throttle position reading.

This cant be changing ignition advance etc alot.

And it has to be supplying more fuel at any throttle positions! Rpm's wont climb at given X throttle position, as the throttlebody opening is as before. But more fuel will be supplied as the EFI thinks the throttlebody is letting in more air, and lean spots will be less lean no matter what.

Its a well tuned motor for sure, but still has head room for less quality fuel etc, so 1-2 dg ignition advance should be problem free.

Yep barley any movement just like your PV on a 2t or between jet sizes. Don't be fooled on the size of movement, little goes a long way.

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Yeah not so much, but I can tell the TPS is sensitive to movement. looks like you don't need the adapter plug to set it up you can back probe the plug at the ECM to get a reading

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2 stroke vs 4 stroke. Its not comparable at all.

Point I was making is just how little the PV moves to affect port timing. Lower your cylinder a little 2t or 4t and see what changes. You assume small movements don't make much of a change but in many places it does. TPS is one of them.

Edited by weantright

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Rotate that TPS freely and Fearlessly! It Richens the fuel/ air ratio throughout the entire rpm range when set to a higher output voltage. A setting of .71 or higher only slightly advances the ignition! This is a mild and harmless ECU tuning tweak. Advancing ignition timing slightly is one of the oldest tricks in the book for getting gasoline engines to make more power especially combined with a richer fuel air mixture. I'm sure if you talk to a KTM dealer they'll tell you otherwise but they would gladly sell you the Grand Canyon. They even sell $15 quarts of oil! The performance gains from these mild changes make a radical difference in your bikes performance it is possible to go a little too rich but the magic of this tool is you can make the adjustments yourself at home or on the trail. The process is simpler than brushing your teeth! Now that my bike is set at .71 with a less restricted exhaust end cap I would never go back to the stock settings. Bike flat lips right now it feels like it's gained about 10 horsepower. The increase in throttle response is phenomenal. My bike with the front wheel effortlessly without the clutch in 1st through 4th gear with the stock gearing I ripped a 62 mile an hour wheelie in 4th yesterday! I can assure you there are no lean spots through the entire RPM range I can tell you this with confidence I've been tuning bikes for over 35 years. If this bike had any lean spots anywhere in the rpm range I would know!

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i had stalling issues and a lean bog off idle before turning my tps to .71 (15fc450) .71 was as far as i could go but it made a huge difference bought the tps tool from the interweb for 39 dollars , worth every penny

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