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Discussion Starter #1
Hi guys,
1998 panther 440 was bogging on acceleration and found out is was my tps.
I saw some videos on how to bypass it but before I do that I noticed that I had quite a bit of play in my throttle cable, maybe 1/2 an inch before it pulls the cable. Do you think this will cause the tps to act up and if so how do I adjust the cable to take out the slack.
thanks for your input.
 

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If I recall, those carbs had throttle safety swtiches, not TPS. The switches are activated by small magnets inside the carb which let the electric system know where the slide is. If there's a mis-match between the throttle position and the slide position, the engine is killed.

The TSS can be a problem with too much slack or too tight a cable. There are also a couple small neoprene bushings on the throttle pin that wear out and can cause a problem with the switches in the throttle block.

To adjust the slides, first turn the slide stops counter-clockwise so that the slides bottom in the carb. Then loosen the jamb nut on the throttle cables and tighten until each slide starts to lift. Then tighten the jamb nut. That should give you a pretty good initial adjustment for the slides.

For an initial slide (idle RPM) adjustment, turn the idle screws in until they barely touch the slide. Then depress the throttle to get the slides out of the way and turn in the idle screws two full turns.

Then check the throttle lever free play. It should be about 0.030". There may be an adjuster on the throttle cable to get that measurement. If the throttle cable does not have an adjuster, rotate the swivel adapters on the top of the carbs equally until you get to that measurement. If the cable is too tight, the TSS will activate and kill the engine. Which is good, if it did not activate, the sled could take off and leave you standing there watching. Not good. ;)

End result is both slides should be just off the bottom of the carb barrel when idling and should lift equally and completely clear the barrel when the throttle is fully depressed.

Aren't carbs fun!
 

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If indeed a rack style short answer yes, give yourself very little movement in cable to bring off idle and adjust that if you adjust air screw and idle speed
 

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Discussion Starter #5
If I recall, those carbs had throttle safety swtiches, not TPS. The switches are activated by small magnets inside the carb which let the electric system know where the slide is. If there's a mis-match between the throttle position and the slide position, the engine is killed.

The TSS can be a problem with too much slack or too tight a cable. There are also a couple small neoprene bushings on the throttle pin that wear out and can cause a problem with the switches in the throttle block.

To adjust the slides, first turn the slide stops counter-clockwise so that the slides bottom in the carb. Then loosen the jamb nut on the throttle cables and tighten until each slide starts to lift. Then tighten the jamb nut. That should give you a pretty good initial adjustment for the slides.

For an initial slide (idle RPM) adjustment, turn the idle screws in until they barely touch the slide. Then depress the throttle to get the slides out of the way and turn in the idle screws two full turns.

Then check the throttle lever free play. It should be about 0.030". There may be an adjuster on the throttle cable to get that measurement. If the throttle cable does not have an adjuster, rotate the swivel adapters on the top of the carbs equally until you get to that measurement. If the cable is too tight, the TSS will activate and kill the engine. Which is good, if it did not activate, the sled could take off and leave you standing there watching. Not good. ;)

End result is both slides should be just off the bottom of the carb barrel when idling and should lift equally and completely clear the barrel when the throttle is fully depressed.

Aren't carbs fun!
Thanks for the info, I’ll mess with it this weekend.
I would love to get some more riding in before the snow is gone.
 

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I have put on more miles this year than the past couple combined!
All from my shop and no travel!
 
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