Trottle position sensor K2 400 carb

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Peterp1per
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Trottle position sensor K2 400 carb

Post by Peterp1per »

Does anyone know what purpose this serves? It wasn't on the X/Y carbed models and obviously not on the K3 onwards as no carb.
Nice Mr Haynes gives no clue, other than how to test it. Curiously it is retained by anti-tamper screws so they don't want you to get it off.

But whatever does it do???

More to the point if it is duff what happens.

Anybody??

kayz1
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Re: Trottle position sensor K2 400 carb

Post by kayz1 »

Tells the ecu where the throtle butterfly is, if the wheels are doing 20mph and the throtle is wide open the ecu then no's you want a bit more from the motor so will alter the timing
just helps smooth out the pulses..i think that is all the early version did but Data will no more..

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Data
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Re: Trottle position sensor K2 400 carb

Post by Data »

Yes, about right Kayz1. It's a buffer between the throttle control and the engine/ecu to give maximum control of engine settings by providing very accurate butterfly/throttle position data (oh...that's me!) to the ecu for optimising engine efficiency.
Probably not ugly enough for the 'Ugly Bunch'! :lol:

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Bluebottle
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Re: Trottle position sensor K2 400 carb

Post by Bluebottle »

Out of interest, on those early models, does it report rate of change?
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Data
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Re: Trottle position sensor K2 400 carb

Post by Data »

Yes...
Probably not ugly enough for the 'Ugly Bunch'! :lol:

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Peterp1per
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Re: Trottle position sensor K2 400 carb

Post by Peterp1per »

Hang on a minute, there is no ecu this is a carbed version, so you are saying there is some intelligence in the ignition control module, beyond just being a cdi unit. So it has engone revs from the pulse pick up and throttle position to work with together with some indication of ambient temperature from a ptc resistor.
I can't see any engine coolant sensor input on the wiring diagram though.

It then outputs the ignition pulses to the coil and a feed to the auto enrichener heater thingy on the carb (just replaced it 100 quid!)

This is all good stuff and I may be able to sort my K2 out after all. Just now I've had to lay it up as I will be away for a bit and it is frustrating me more than somewhat.

Thanks for your help.

SH125Paul
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Re: Trottle position sensor K2 400 carb

Post by SH125Paul »

TPS / resistor value is used by the ECU to sort out the advance / retard of the ignition timing...

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Re: Trottle position sensor K2 400 carb

Post by Data »

Peter, sorry didn't notice this is carbed. Have to say I'm not sure about the full TPS functions and reporting on the carbed version. But it's likely it will still be reporting back to the cdi in some form.
Probably not ugly enough for the 'Ugly Bunch'! :lol:

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