Bagstr 288 Posted August 7, 2014 Learning a bit from the TPS Testing thread. Moving here to work with actual adjustment issues. KTM Manual lists TPS output voltage @ 0.601vdc +- .004 Idle approximately 2000 rpm These Injected KTMs are typically hard starters. The Dealers roll their eyes, as if to say get used to it. My 350 with 215 hrs has never started from cold without the choke from new. I set the TPS last year with minor improvement. Significant popping on deceleration. (Lean? ) xcw Map. Typical routine is Choke / Crank, Crank,,,Crank 5-10 seconds - reluctant start. If I don't leave the choke on for 4 minutes or so, the bike will stall and be even harder to start. Then u need wait 5 minutes and resume choke/crank. Never an acceptable situation. New Strategy The TPS Cable Thread started by Chad put my mind in motion, and you know a mind in motion is a danger. The Testing Cable will be a good tool to verify results, but I have come the the conclusion that running condition is a superior indicator than the factory setting. Really, they may have different priorities. Reading the ADVrdr TPS post from '13 mentions the alternate strategy of what I call " Free-hand" adjustment. Mmmm. While waiting for my cable connectors, let's do experimenting! A. Loosen locking screw, fudge cap counter clockwise, tighten. = From Cold, bike started immediately. While riding, little to no popping on deceleration. Unfortunately, a little hesitation off idle. B. Rotate cap to middle of adjustment range. = Started immediately from warm. While riding, smooth off idle response. C. Rotate cap just a schooch counter clockwise. = Started immediately from warm. While riding, good throttle response. This morning from overnight cool-down, Just barely will not start without choke. With choke, started immediately. pushed in choke after 30 seconds and bike continues to idle. I bought one of the $15 Hour / Tach from MotoW and will use to set idle at 2k rpm. Conclusion: The goal is to have a well behaving moto even if that means creating a new spec. It will be interesting to read-out the voltage when I get the cable made. Thanks to PbdBlue, Amgems, Chad and others for adding to the discussion. Bagstr Share this post Link to post Share on other sites
paulmbowers 236 Posted August 7, 2014 Wow. Something's up. My 500: Turn key to ON. Press button. Ride. Share this post Link to post Share on other sites
Bagstr 288 Posted August 7, 2014 I sincerely hope (sic) your bike continues to perform well once you get more than 15 hours on the motor. Wow. Something's up. My 500: Turn key to ON. Press button. Ride. Share this post Link to post Share on other sites
PbdBlue 46 Posted August 7, 2014 My 350 (eu map, tps = .61 volts) starts right up. Only need the start idle button on very cold mornings after setting for awhile. Share this post Link to post Share on other sites
paulmbowers 236 Posted August 7, 2014 I sincerely hope (sic) your bike continues to perform well once you get more than 15 hours on the motor. Yeah, me too! But I suppose that asks the question- what about the number of hours on the bike might explain the problem? Engine wear? Injector wear? Share this post Link to post Share on other sites
PbdBlue 46 Posted August 7, 2014 One concern is fuel quality. Since dirt bikes sometimes sit for long intervals between usage there is ample opportunity for the fuel to degrade and cause contamination to form. I've been using Seafoam in the fuel when I think the bike will sit awhile. Share this post Link to post Share on other sites
Chad 0 Posted August 7, 2014 I was having starting problems similar to Bagstr prior to my tear down. Most days, cold start was a kick. I have heard that this might be due to battery not having quite enough juice to kick the engine over. I did experience consistent deceleration pop. (I am running an FMF MegaBomb and 4.1 RCT muffler (both Ti). I understand that may add some varialbles...) Hadn't really noticed any hesitation off idle, but could've easily just not noticed. At rebuild, I set my TPS at .61 per spec with the bike running using a TPS harness (Thanks Kevin!). I wasn't able to accurately asses cold start ability because I had run my battery down to far (wouldn't crank). And I couldn't kick start. I jumped it off my truck, but still wouldn't E-start. (So I guess there's my answer.) Was able to kick start it at that point. SIDE Q? - We tried for 5+ minutes to kick it with the battery low and she wouldn't start. Speculate there was not enough voltage to get the fuel pump to prime the system. Can anyone confirm? After start, ride was great. The deceleration pop is still there, but seems to be lessened some. I plan to play with the setting a bit too. Will try BDS's recommended setting and see what that does for me... Look forward to hearing other's input and results. I'm riding again this weekend, but do not have the harness to "accurately" play with the TPS. May try Bagstr's "freehand" method and see what happens. Will post up if I have anything worth relaying... Thanks! Share this post Link to post Share on other sites
dirt dame 561 Posted August 7, 2014 I like my carburetors. Just sayin'..... Share this post Link to post Share on other sites
Spaugh 1 Posted August 7, 2014 Wow. Something's up. My 500: Turn key to ON. Press button. Ride. Dito, the idle may need to be turned up dave. Try running 3k and see if it helps. You are barely above the auto decomp point at 2k. Guarantee factory ktm race bikes have the idle set 2x higher than yours.Also just barely crack the throttle open while pushing the starter button. Does tjat help? Share this post Link to post Share on other sites
Chad 0 Posted August 7, 2014 I should add... I have the standard US MAP, but have the KTM factory MAP switch and primarily run it on "wild". Also, just put on an FMF Grunt where the pipe meets the cylinder. I run a Golan 10 micron mini filter b/w the tank and injector and StarTron enzyme fuel treatment. Also just replaced the filter on the fuel pump inside the tank. Even with the StarTron, my throttle body was gummed up with a yellowy crud that resemble scale from water. I've heard talk that is related to various additives CA requires in fuel sold in the state. Haven't researched it and don't really intend to start a long discussion on that topic at this point... Share this post Link to post Share on other sites
kato 54 Posted August 7, 2014 Guarantee factory ktm race bikes have the idle set 2x higher than yours. 4000 rpm idle really?? Share this post Link to post Share on other sites
Chad 0 Posted August 7, 2014 Not to take the thread off direction... This gent in OR has done some pretty cool stuff with his '12 350 EXC-F and he's done one hell of a job documenting it. I've made a number of the mods he explains. Thought it might be a good resource for other 350 owners who might not be aware of it. Here's the beginning of the thread: http://www.omraoffroad.com/forum/viewtopic.php?f=40&t=11373&sid=96ec942bc3ba20cbaeabf811b0eb270f Here's a link to the page within the thread that has a hyperlinked Table of Contents of sorts (about 1/3 down the page): http://www.omraoffroad.com/forum/viewtopic.php?f=40&t=11373&start=180 Hope this is helpful to some... Share this post Link to post Share on other sites
paulmbowers 236 Posted August 7, 2014 Yeah- it's swiped from KTMtalk... Share this post Link to post Share on other sites
amgems 79 Posted August 7, 2014 Just as a reference point: My idle is set to 1950-2050 as per spec. The idle speed adjuster knob has clicks and if I go one click left or right the idle speed gos out of this range. I think it ended up like 2025 or 2045. The tps is set to spec .601 +/- .004. It starts within 1 - 3 seconds with "choke" when cold. Once it's warmed up it will start without choke in 1 - 3 seconds. Have only ever kicked it once or twice. Just to see if I could. The tps is super super sensitive when adjusting it. Just the smallest (really really small) movement will change the voltage drastically. I think that is why it goes out of adjustment after time. Heat, vibration, etc. allow it to move a few 1/10's of a degree over time and then it is no longer in spec. There are other things to consider if after setting everthing to spec, and you still have starting that takes more than a few seconds, or you have to kick it to start it. Fuel pressure has to be 50 psi. The filters have to clean. The injector may need cleaning. If this is all good, then it's time to look deeper at compression, electrical, mechanical, etc. Share this post Link to post Share on other sites
robertaccio 412 Posted August 7, 2014 FI bikes are set up very lean in mapping. . old fuel. fuel filter. fuel injector (ask me or Rev5 how I know this). Fuel pump. fresh plug. nice machine get er dialed!! Share this post Link to post Share on other sites
HotRod82 2 Posted August 7, 2014 ......this thread (and 100's just like it on ktmtalk) is why I just dumped $4K into my old 07 525 instead of buying something new. I must be getting old and cranky. lol. Share this post Link to post Share on other sites
paulmbowers 236 Posted August 7, 2014 Aw, come on. Plenty of carb issues in the past. Bikes is bikes. Share this post Link to post Share on other sites
Strega 0 Posted August 7, 2014 Wow. Something's up. My 500: Turn key to ON. Press button. Ride. Share this post Link to post Share on other sites
Bagstr 288 Posted August 7, 2014 Like my grandpa, I like solving these issues. Although, I have thought seriously of building a Steve McQueen issue Triumph. Share this post Link to post Share on other sites
