1 1985 K100RS throttle position switch Mon Mar 26 2012, 14:17
brickrider
Life time member
I've read with interest all the postings I could find related to the mysterious throttle position switch (TPS). I foolishly moved the one on my bike in the course of renewing the fuel hoses and other rubber bits. Now its all back together and I find the overall running is worse that when I began the work
I've done all I can to refine the set-up of the bike, following the description in the Haynes workshop manual and various posts here. I now have concluded the TPS was not functioning when I bought the bike last autumn, because it accelerated and slowed without a trace of lurching. Having adjusted the unit, the bike now is not nearly as smooth running. Okay, so much for preamble. My question is this: to render the TPS non-operational, can I just loosen the set-screws and slide it down to its extreme (lower) range of adjustment or must I physically remove the plug-in cable?
In spite of all the posts on this subject, I continue to be unsure of its role in engine management. If it cuts fuel to the injectors at closed throttle, why does the engine continue to idle at all? I've read that there are actually two switch modes. The first "click" should be heard as the TB plates just begin to open, and another "click" at WOT to increase fuel to the injectors. I was able to adjust the unit so it clicks when the TBs first open, but I do not hear a click when the TBs are completely open. Would this indicate the TPS is defective?
Thanks for your advice and insights.
I've done all I can to refine the set-up of the bike, following the description in the Haynes workshop manual and various posts here. I now have concluded the TPS was not functioning when I bought the bike last autumn, because it accelerated and slowed without a trace of lurching. Having adjusted the unit, the bike now is not nearly as smooth running. Okay, so much for preamble. My question is this: to render the TPS non-operational, can I just loosen the set-screws and slide it down to its extreme (lower) range of adjustment or must I physically remove the plug-in cable?
In spite of all the posts on this subject, I continue to be unsure of its role in engine management. If it cuts fuel to the injectors at closed throttle, why does the engine continue to idle at all? I've read that there are actually two switch modes. The first "click" should be heard as the TB plates just begin to open, and another "click" at WOT to increase fuel to the injectors. I was able to adjust the unit so it clicks when the TBs first open, but I do not hear a click when the TBs are completely open. Would this indicate the TPS is defective?
Thanks for your advice and insights.