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Discussion Starter #1
i noticed this the day before my wreck, and again today. the bike is very prone to stalling when starting out for the first ride of the.day. when warm my idle will fluxuate about 1-200 rpms. it has also stalled at a couple stoplights when warm. this seems likea fuel reg issue from what i have read. any other ideas before i go buy a new one?
 

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Make sue your plugs are ok and haven't fouled.
If you decide to get a regulator make sure you get the latest as they have been redesigned a couple of times and as it may be crosslisted they may stock an older one.

Subsailor on an other thread noted they have vacuum lines going to it and if those leak the regulator may malfunction, so check them before you buy one. As RCs seem to have this problem it may be a wise part to stock for spare.
 

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Discussion Starter #3 (Edited)
the stalling started after i changed my plugs, but i attributed it to a low idle cause i was sitting at 1000 rpms after plugs, flapper, and pair mod. after i cranked up the idle to 1300 it is still doing it. i also noticed yesterday that with the fast idle all the way out i never got above 1700 rpms, where previously i was sitting at about 2000


i guess the logical thing would be to pull the plugs and check em

I know on my old bikes a bouncing idle, was normally caused by carbs outta sync, or a vacuum leak. but since there are no carbs on this bike, i should prolly look for a vacuum leak. Is the slight bounce normal? it is literally only +\- 100 rpms over 1300

the other thing is, right after warm up if when it stalls it seems to not want to crank back up. it prolly take s a good 10 sec of hitting the started to get it to start. When it does start it seems to stumble starting. When the bike is at full operating temp, it fires right back up instantly.

im very confused on this, im going to check the plugs tonight when i get home.
 

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Discussion Starter #4
ok so i went for a ride yesterday, the bike was idling low till about 180 degrees and then it smoothed out. didnt shut off at all yesterday. never had a power issue during all of this. never pulled the plugs but if it does it again i will.
 

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Discussion Starter #5
ran perfect all.day.... then after it sat at the gym for 4 hours it stalled at the light leaving. it was warmed up to around 150 degrees at the time
 

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Discussion Starter #7
im guessing since it all started when i did plugs and pair/flapper that maybe i pulled cracked a vacuum line loose or something. my replacement tail came in today so ill be working on the bike anyway so ill check. i did notice that when it was 77 degrees outside it didnt have a single problem with stalling.
 

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im guessing since it all started when i did plugs and pair/flapper that maybe i pulled cracked a vacuum line loose or something. my replacement tail came in today so ill be working on the bike anyway so ill check. i did notice that when it was 77 degrees outside it didnt have a single problem with stalling.
I just did the flapper mod/removal. No issues at all.
 

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Discussion Starter #9
im thinking if i did knock something loose it happened during pair removal due to work
ing around throttle bodies
 

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Discussion Starter #10
im betting the fact that my airbox didnt get hooked back to my oil catch causing a airleak of unmetered air might have been it!
 

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I don't think the airbox would be the main problem.
The MAP sensor for manifold pressure is mounted on the throttle bodies.

A loose hose to the throttle bodies causing an air leak would cause problems.
Especially the hose on the front throttle body that went to the flapper vacuum tank after flapper valve removal.
That should be blocked off.
 

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Discussion Starter #12 (Edited)
that is blocked off, and fuel regulator wasnt leaking into vacuum line that i could tell.( pulled line no gas out so im guessing the diaphram is ok). vacuum lines looked in good shape with no cracks. that was the only thing i could find at all. other than the stalling bike runs great. it only seems to do it between 150 and 180 degrees so far. also never has done it when just idleing before being.ridden
 

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Discussion Starter #13 (Edited)
so i jumped the green connector, all i got was a solid red fi light. does that mean no codes? just looked in manual no blinks means faulty ecm? im confused it says symptoms are engine runs normally
 

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so i jumped the green connector, all i got was a solid red fi light. does that mean no codes? just looked in manual no blinks means faulty ecm? im confused it says symptoms are engine runs normally
Hmmm...says a solid lit FI light means either a short in the service connector wiring or a faulty ECU.

Just to try, have you pulled the ECU connectors and checked for tarnished/corroded pins? While at it, put a healthy dab of dielectric grease on the pins as well.

Plus you've checked to ensure your ground wire on the right side of the frame has a clean metal to metal contact and the bolt is tight? This has caused odd problems as well.

Otherwise, it might be a faulty ECU (it's electronics, and they do fail at times).

If you decide to replace it, Ben at RC51Parts.com has an SP2 ECU far, far, cheaper than a new unit.
 

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Discussion Starter #15 (Edited)
ill check those tonight. it is just strange that it didnt do it till i did plugs and flapper/pair. in the manual under refer to page it just has a "-" could it be throwing this code due to a super crappy stripping job on my jumper wire? when we jump the connector, wouldnt that cause it to show the short in service connector code?
 

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Discussion Starter #16
few pages back........" if the ecm has no problem.data in memory, the mil will come on and stay on"



im a idiot. should have read the whole section and not just the codes
 

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Discussion Starter #17
took the bike out for a lil bit yesterday, and the problem didnt show itself again. im hoping that it was just the tube on the airbox being off. i know on old carb bikes a airbox leak causes all sorts of strange stuff to happen, so hopefully im good now
 

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This damn issue is still going on??? Is there a connector, hose clamp, fastener you haven't touched inthe last month in this bike?:D

I hope you find a root cause and take care of it...this intermittent shit is a killer
 

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took the bike out for a lil bit yesterday, and the problem didnt show itself again. im hoping that it was just the tube on the airbox being off. i know on old carb bikes a airbox leak causes all sorts of strange stuff to happen, so hopefully im good now
I had that same tube off on my airbox for a while and it did nothing to the way the bike ran. I did however have an issue with my fuel pressure regulator and it did all of these intermittent things. I bought a new one and when I put it on I noticed that the old one had a build up of corrosion in it. Someone told me they thought it could be form the ethanol we have here in Florida. Could be bull but there was crap in my regulator I did see that.

Anyway, the new one fixed the problem.

Then again, I also had a bad ECU at one time that would stop my fuel pump for no reason. Had to replace that too. But that was before the pressure regulator issue.
 
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