Craig Posted February 28, 2015 Share Posted February 28, 2015 I decided to adjust the TPS and balance the throttle bodies today. The bike is running fine, so I am not trying to solve a problem, just due diligence. I have the transfer rod disconnected, the choke cable loosened, and the idle adjust screw backed off completely. I am measuring 631mV! Far from the expected 150mv. I have not ruled out something internal to the throttle body keeping the butterfly open, but I have a different problem. I can't get the TPS screw loosened. They appear to be 3mm pan head cap screws. I can't get them to budge and I do not want to round them out. Any hints here? Link to comment Share on other sites More sharing options...
czakky Posted February 28, 2015 Share Posted February 28, 2015 From the factory they are "star" bits. Make extra sure you have the choke cam out of play as well not just the cable. Also could be some gunk in the way of the butterflies in the throttle bodies, give em a spray with some carb cleaner. Link to comment Share on other sites More sharing options...
Craig Posted February 28, 2015 Author Share Posted February 28, 2015 From the factory they are "star" bits. Make extra sure you have the choke cam out of play as well not just the cable. Also could be some gunk in the way of the butterflies in the throttle bodies, give em a spray with some carb cleaner. I pulled them out using vice grips. I replaced them with stainless SHCS. They didn't look like TORX bits, I will have to look again. They had a yellow seal marker that looked undisturbed. Was that from the factory? I am the second owner. I reset everything according to the procedure. Seems to run fine. Next fuel up will tell more. Link to comment Share on other sites More sharing options...
fotoguzzi Posted March 1, 2015 Share Posted March 1, 2015 yep the yellow paint is from the factory after they supposedly set and balanced everything. Link to comment Share on other sites More sharing options...
docc Posted March 1, 2015 Share Posted March 1, 2015 There are two idle set screws, one on each side, and two high idle cam fasteners. Be sure they are all released and the butterfly is not sticking in the throttle bore. The factory yellow paint is there to help you find all the points that need to be fettled. 1 Link to comment Share on other sites More sharing options...
Kiwi_Roy Posted March 1, 2015 Share Posted March 1, 2015 If you flick the throttle with your finger you should be able to hear the butterfly making contact with the throttle body. I found setting my high mileage bike with the butterfly closed the mV would change slightly each time I blipped the throttle, so I modified the procedure a little. I use a strip of paper as a feeler to find the point where the zero screw makes contact. wind it in from there one flat then with the throttle just resting on the stop I adjust for 150 mV. Dropping the TPS from 631 to 150mV the bike will run leaner but not as much as you might expect. I had a fuel mixture meter on mine for a while with a pot that would allow me to offset the mV on the fly, I had to add a lot of millivolts to change the mixture by 1% Link to comment Share on other sites More sharing options...
Craig Posted March 1, 2015 Author Share Posted March 1, 2015 I like the instrument cluster! I may do this again and completely pull the throttle bodies to clean them. It seems to run fine, but there is a bit of surging around 3K that wasn't there before. Link to comment Share on other sites More sharing options...
stewgnu Posted March 1, 2015 Share Posted March 1, 2015 Damn that 3k surge. Well worth checking intake bootses for any crackage... Link to comment Share on other sites More sharing options...
docc Posted March 2, 2015 Share Posted March 2, 2015 I like the instrument cluster! I may do this again and completely pull the throttle bodies to clean them. It seems to run fine, but there is a bit of surging around 3K that wasn't there before. At least on the early RedFrame, the throttle body assembly will not come free without separating the frame and driveline. Link to comment Share on other sites More sharing options...
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