RHill Posted July 4, 2016 Report Share Posted July 4, 2016 Need some help figuring out this problem: Seemingly cleared up right at the end of the video, but on the final turn on the front straight, the bike feel back on it's head as I pitted in. Only things done since the previous track day where the bike ran fine; changed oil and swapped out steering damper. Disconnected Power Commander and quickshifter. Fuel flow from the tank seems fine (primed the pump into a bottle). Exhaust temp across cylinders seems even via IR gun and wet rag test. Charging system is disconnected to isolate another issue. Upon the last test 2 minutes ago, the bike was a bitch to get fired up and idling, but after it heated up a little and a restart; the throttle response seemed close to normal. Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted July 5, 2016 Report Share Posted July 5, 2016 Sounded like fuel starvation. Intermittent problems like that are a real bitch. You could swap in a known good fuel pump, or maybe find a way to monitor pressure at the fuel rail while riding to see if it is indeed dropping. Aside from that, go over all associated wiring and make sure there isn't an issue there. This is why I prefer carbureted bikes. 1 Quote Link to comment Share on other sites More sharing options...
RHill Posted July 5, 2016 Author Report Share Posted July 5, 2016 I've got another fuel tank/pump that I can throw on......have to swap the gas out that is in the tank though, been sitting for over a year. Plan to check & swap the plugs out with the ones from my 600, probably swap the tank after....just so I'm only making 1 change at a time. Earlier in the day, putting around in the pit, it definitely had a miss going on as well. Really hoping it is just a coil that is just sitting on top a plug or some other stupid thing. Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted July 5, 2016 Report Share Posted July 5, 2016 Did it feel like it had only dropped one cyl or more like a total failure? Single cyl might point to c.o.p., or maybe single injector failure but not likely. Sounded to me like you went way lean all the way across the bank for a little while. Quote Link to comment Share on other sites More sharing options...
Bubba Posted July 5, 2016 Report Share Posted July 5, 2016 (edited) Not gonna claim to be know-it-all when it comes to modern FI bikes, but while you've got her unbuttoned, you might do a comprehensive check of your electrical connections and the major ground points for the wiring. Could be something like a loose ground strap or oxidized/corroded/burnt connector in the loom wreaking havoc with your voltage to the ECU or pump. Nothing says "electrical" more that an intermittent problem. Just a thought. Edited July 5, 2016 by Bubba 2 Quote Link to comment Share on other sites More sharing options...
RHill Posted July 5, 2016 Author Report Share Posted July 5, 2016 1 hour ago, CrazySkullCrusher said: Did it feel like it had only dropped one cyl or more like a total failure? Single cyl might point to c.o.p., or maybe single injector failure but not likely. Sounded to me like you went way lean all the way across the bank for a little while. Rolling around the pit, just a single cylinder for sure. On track, in the video, I initially thought I had lost it all, but it didn't throw me forward like the bike was trying to bump start itself. Had a loose ground once; it would kill the bike, then bump start, then die, bump start again. The deceleration from the loose ground was MUCH worse, so I'm assuming it wasn't all 4 cylinders; it didn't feel much different from coasting. "c.o.p.?" Might just be coincidence, but the two time it happened on track were both left hand turns 1 minute ago, Bubba said: Not gonna claim to be know-it-all when it comes to modern FI bikes, but while you've got her unbuttoned, you might do a comprehensive check of your electrical connections and the major ground points for the wiring. Could be something like a loose ground strap or oxidized/corroded/burnt connector in the loom wreaking havoc with your voltage to the ECU or pump. Just a thought. I'll have dive into that a little deeper.....checked continuity on all the fuses and some connections, but once the tank and airbox are back off, the search will continue. Did notice that my Power commander TPS light comes on when the tank primes, but turns off after.....then comes back on after the bike fires up(and moves with the throttle like it should). Not sure if it is suppose to turn off if the bike is not running. Only FI code that is being thrown is the PAIR valve, which I disconnected and installed resistors in place of, but it keeps throwing the code.....same code has been thrown for the past 6 months with no issue. Quote Link to comment Share on other sites More sharing options...
Trackbikez Posted July 5, 2016 Report Share Posted July 5, 2016 2 hours ago, RHill said: I've got another fuel tank/pump that I can throw on......have to swap the gas out that is in the tank though, been sitting for over a year. Plan to check & swap the plugs out with the ones from my 600, probably swap the tank after....just so I'm only making 1 change at a time. Earlier in the day, putting around in the pit, it definitely had a miss going on as well. Really hoping it is just a coil that is just sitting on top a plug or some other stupid thing. I think you're going down the right path here. Both my bikes had similar issues at different times One time it was a bad tank of fuel, the other was dirty spark plug. Issues corrected themselves with fresh fuel and new plugs on both bikes. Simple stuff first before you go tearing into the TPS and FI system, especially if it's not throwing codes (or any "new" codes in your case). Quote Link to comment Share on other sites More sharing options...
RHill Posted July 5, 2016 Author Report Share Posted July 5, 2016 Well, after changing the plugs for some old ones, removing the quickshifter wiring and checking over some of the remaining wiring, the issue persists. Plugs looked OK, running rich, but not bad. Started up easier(did just fire it up before changing anything to verify it was still being a pain). When blipping the throttle, there is a split second delay and then it takes off. Didn't bother taking off the trailer yet, but I'm 99% sure if I putted around, it wouldn't feel good. Just checked the part numbers, 04/05 600&750's all have the same injectors, so my plan is to swap them from an engine I have laying around....unless something else clears it up first. I don't think it is a clog in the tank pump or filter, because I wouldn't think that would cause instantaneous blip lag. At a loss and getting more and more frustrated. Any input or ideas are greatly appreciated! Quote Link to comment Share on other sites More sharing options...
Vagabound Posted July 5, 2016 Report Share Posted July 5, 2016 In my experience, issue like this could be fuel pump. But I'd make sure tank is clean, fuel filter replaced. Also dump the fuel out of the gas tank and put known good gas in. Quote Link to comment Share on other sites More sharing options...
RHill Posted July 5, 2016 Author Report Share Posted July 5, 2016 7 minutes ago, 0hi0 said: In my experience, issue like this could be fuel pump. But I'd make sure tank is clean, fuel filter replaced. Also dump the fuel out of the gas tank and put known good gas in. Just got off the phone with someone who said about the same thing.....guess who is going to swap tanks now....damnit. Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted July 5, 2016 Report Share Posted July 5, 2016 Oh it's not that much of a job. At least you can just swap the entire tank, pump,filter as a unit. If it fixes the issue you can check individual items you took off. If it doesn't fix it, you can rule out everything up to the fuel rail. Quote Link to comment Share on other sites More sharing options...
RHill Posted July 5, 2016 Author Report Share Posted July 5, 2016 Well, swapping tanks didn't seem to change anything. Not trying to make a big deal out of changing the tanks; I'm just frustrated grasping blindly at straws trying to figure this out. I'm starting to wonder if swapping the plugs and ensuring the coils were seated corrected the issue....firing up easy everytime now, but it is also heated up. Rolls on smooth, but if I snap it open there seems to be a moment of hesitation.....could have been there before and I just never paid attention to it. I'm going to let it cool down fully to see if it gives any trouble starting like it did before. Have to say though, it would barely idle when I brought it home....swapping the plugs and reseating the coils gave it a nice steady idle from the first start. Quote Link to comment Share on other sites More sharing options...
RHill Posted July 5, 2016 Author Report Share Posted July 5, 2016 Plugs are less than a season old iridiums. It could have just been a loose coil, but they seemed secure when removing them initially. Quote Link to comment Share on other sites More sharing options...
RHill Posted July 5, 2016 Author Report Share Posted July 5, 2016 Other thing I just thought of...when running it yesterday(in an enclosed garage), the exhaust fumes got to me much quicker.....this time, it wasn't nearly as bad after running longer and harder. If it was spewing unburnt fuel before, that could be an explanation....if it is burning now, would make sense the fumes would be a little less harsh. And yes, running an engine in an enclosed space is stupid. Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted July 6, 2016 Report Share Posted July 6, 2016 We all agree you're stupid. Check resistance on coils, coolant temp sensor against values in fsm. Failing that, cram a grilled cheese sandwich into the intake funnels for number 2 and 3 cylinders. Quote Link to comment Share on other sites More sharing options...
RHill Posted July 6, 2016 Author Report Share Posted July 6, 2016 fun fun fun pulled the airbox off and hit the kill switch....the svta jiggled around, but didn't actuate. Weird! I had already checked this the first time the airbox came off. Hit the killswitch a few more times while stressing the connector...could disable and enable it with very little pressure. Quick google of how to fix it, popped it apart and re-soldered the connections and reinstalled. First time I only soldered the one connection that was visibly broken. Put it back together and it still didn't function. Pulled it back apart and re-soldered all 4 connections, works now while applying pressure to test it.. Hoping that was the issue, but I have a few other things I want to take a look at while I've got everything apart. I've been getting a C49 code constantly which is the pair valve malfunction. Tore into the the bike and verified the resistors were correct(20ohm) and traced it all the way back to the ECU. There is no reason it should be throwing a code?!? Printed out the coil resistance info; need to verify that and a few other things before it goes back together tomorrow. Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted July 6, 2016 Report Share Posted July 6, 2016 Munster and Havarti on sourdough. Quote Link to comment Share on other sites More sharing options...
RHill Posted July 6, 2016 Author Report Share Posted July 6, 2016 both on one sandwich split into both cylinders, or one cheese per cylinder? velocity stacks matter? Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted July 6, 2016 Report Share Posted July 6, 2016 Don't dwell on details. Just mash it in. Or make 2 sandwiches and I will come eat one while I demonstrate proper motor sandwich mashing technique. Quote Link to comment Share on other sites More sharing options...
motocat12 Posted July 6, 2016 Report Share Posted July 6, 2016 Use the velocity stack to punch off the crusts Gixxers hate crust. 1 Quote Link to comment Share on other sites More sharing options...
RHill Posted July 6, 2016 Author Report Share Posted July 6, 2016 made myself a crustless PB&J using the velocity crust cutters 1 Quote Link to comment Share on other sites More sharing options...
Jester_ Posted July 6, 2016 Report Share Posted July 6, 2016 1 hour ago, RHill said: made myself a crustless PB&J using the velocity crust cutters Little circles of Heaven. As long as its grape jelly.... 1 Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted July 6, 2016 Report Share Posted July 6, 2016 What have I created? Quote Link to comment Share on other sites More sharing options...
Jester_ Posted July 6, 2016 Report Share Posted July 6, 2016 PB&J Oreos apparently. Quote Link to comment Share on other sites More sharing options...
RHill Posted July 6, 2016 Author Report Share Posted July 6, 2016 only if they are double stuffed we need more paraffin! 1 Quote Link to comment Share on other sites More sharing options...
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