Originally Posted by soft 02

Iclick. Thanks for the update. Last year I had the freeway stumble and it was the TPS at fault. I too believe that changing them every years is a good idea or keep one on hand.

Originally Posted by soft 02

When it happened to me I took a guess it was the TPS. Now I've changed out a total of six of them. Guess only a few of us have this issue.

Originally Posted by nvsteve

Not too long after the 07 bikes were released a letter went out to owners regarding a re-flash of the ecm. I believe it added fuel in some areas, maybe reduced some timing.
I'd guess that's what he was referring to.
By the time I received the letter I had already added a PC111 from Fuelmoto and had it tuned. Three dealers and a couple tuners suggested I not get the reflash. I think I may have even checked with Jamie.

Originally Posted by kpb46

i never got a letter

Originally Posted by iclick

After starting this thread back in 2010 and watching it stay alive through the past three years I have yet another report to make. Last fall I had a revival of the high-idle issue I reported originally and it recurred several times until the weather turned cool when it stopped for several months. This spring it has returned and has become common lately, sometimes starting as a high idle followed by a low, stumbling idle that would nearly kill the engine. One symptom reported previously but not experienced with the latest issues was a rare and sporadic misfire at highway speeds.

I have been watching TPS voltage on my Power Vision display unit for some time and have noticed that at idle it has been jumping around rapidly between .15-.52v but smooths out and stabilizes as TP and TPS voltage increase. It should read around .50v at idle. Having seen these symptoms before I was sure the TPS was at fault so today I changed it again only 16k miles after the last in June 2011.

I took it for a test ride and noticed that TPS voltage at idle had stabilized between .51-.53v, a marked improvement over the old defective unit. I looked at it and noticed that at the 0% TP position (idle) that the center section that moves with the throttle shaft was looser than in other positions. I put an ohmmeter on it and noticed that if I moved the center section laterally--i.e., not linearly as it would move in normal operation--the ohmmeter would fluctuate, which it clearly should not, but if I moved the mechanism off the idle position it did not change.

My conclusion is that somehow the TPS mechanism is wearing at the idle position, probably due to engine shake. The '07 96" engine on the old frame produced more shake than in previous models and I'm wondering if this is the cause--excessive shake causing the TPS to wear prematurely. A friend with an '06 RG (stock 88" engine) has 47k and he has had no problems with the TPS, but his bike idles much smoother than mine. The '08 had the same frame and engine but had no TPS, so the '07 is the only year model with this combo (old frame, old engine-mount design, 96" engine, and TPS). I also wonder if maybe the throttle shaft may not be quite straight, causing the TPS mechanism to wear prematurely as it shakes at idle.

I think I'm going to have to resign myself to changing the TPS every two years or so, which I can handle. At $32 and taking only maybe 20 min. to install it just isn't a big deal. About 10 min. of that is to remove the AC hardware and another 10 min. to remove and re-install the inner bolt, which is difficult to access. For that I used a small Torx bit that normally fits inside a ź" socket, but for this job I slipped it inside a ź" ratcheting box-end wrench. I thought about going to Ace Hardware and buying an Allen bolt instead, which would be easier to install with a long ball-end Allen socket, but it just isn't that difficult with the stock Torx bolt.