PJPR01 Posted January 23 Report Share Posted January 23 A project years in the making...finally tackled it...but not happy with results. Having finally decided to tackle the TPS setting, despite having no issues, I figured it was time to do the 1 thing I have never done on the Tune up list, after having done absolutely everything else on the list with meticulous attention. I connected the new Casper cable (so that's how it works...aha!), connected the voltmeter, disconnected throttle linkage and see the TPS is registering 0.350mv...well, that's supposed to be .157...hhm, I wonder why the bike runs well despite that, I ponder. Thinking, well surely it will run even better when I set it properly! Premature delusions of grandeur dancing in my head! Ok, remove the old TPS, look inside, pretty oxidized with some crud, so I clean it out thoroughly, re- connect the TPS, back out the idle screws on both sides so they are not touching the cams, snap the RH throttle several times until it's well and truly seated and get it set on the nose at 0.157mv, and snugged in tight. All good, put it at full throttle still disconnected from the linkage, and it reads 4.70...sounds like I'm in the right range. Ok, mission accomplished on the TPS. Connect it all back up again, remove and clean air screws, blow some throttle body cleaner into the TB's, then set the air screws 1 full turn out each, reconnect linkage, get idle screws touching, bike idling like crap, and tons of flat spots and coughing. Put a fresh set of plugs in just for fun also. Cranked it up, idling low, and start adjusting as per the write up here. Played with it a few more times, getting it nicely balanced with the Carbtune, idling beautifully, air screws 1 full rotation turned out, and I still have a flat spot/cough at low rpm's (1.5K to 3k RPMs') that was NEVER there before. Disconnected everything again, and go thru each step methodically, recheck TPS with linkage and idle screws backed out, and still seeing 0.157 closed and 4.70 at WOT, hook it all up again, but no change in behavior. I'm thinking do I have something clogging up fuel lines or something so I take it for a short ride, but not at all happy with the flat spot/cough. So...decided to buy a new TPS as recommended by Docc...came in a few days, installed it today, and noticeably smoother and I can see it moving in increments of 0.01 easily as I gently tap...so here we go again, set to .157mv and full closure with linkage and idle screws backed out...and 4.70 at WOT. Figure it will run better, and it does...but bugger all, it still has a cough. How is it possible that I could have had NO flat spot or cough ever in the prior years of running, with a TPS obviously set at the wrong point, and now with every thing exactly on spec (or obviously I'm overlooking something), I have it idling perfectly, Carbtuned and balanced to perfection at idle and 3K rpm's and I still have a flat spot/cough. I even went around and snugged up all the new rubber intake boots 3 clamps each side, snugged up exhaust headers (no movement), connector pipes (2 each side). It runs beautifully on the highway, but now, every time I come to a stop I know it's going to stumble when I take off again...until I get above 3 k RPM's again. I know it's not relays, since I had no issues before, no exhaust leaks, fresh rubber, valves set, fresh plugs...WTF? and just for fun I went and put a fresh full tank of new gas in it...no change. Back to the drawing board here...surely I'm missing a step somewhere... Link to comment Share on other sites More sharing options...
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