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Discussion Starter #1
Hey guys I’ve been browsing forums for about two months looking for someone who has had the same problem but I may be alone on this one. Looking to get some fresh ideas on this issue.

Bought an SP1 from a mechanic who got her running after she was wrecked on the track. The last problem he had ended up being a wire shorting against the frame causing the bike to stall. After I purchased the bike and 3 months of happy riding The FI light would come on when I’d hit a bump and it would stall for about 2 seconds then kick back to normal. This progressed over the next week to the point it would just stall every 10 feet or so making it more of a bucking bronco then a bike.

Cleared the stored codes and now I’m getting no fresh codes. I’ve checked all the wires and can’t find anything that would be shorting against the frame. I took the plugs out, cleaned them, and it seemed to clear the problem for about a month. Ordered new plugs, but problem still exists.

The bike idles fine, can lay on the throttle, shake it, it, and nothing will cause it to stall until you ride it, especially riding a bump or the such on back roads, highway isn’t as bad.
I’m out of ideas here other than combing every wire on the bike. :confused:
 

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It seems like I'm always saying this but, man one time I'm gonna be right..lol

I would try cutting the wires to your kickstand switch and splicing them together. I have seen this happen on many different bikes of all makes and models. The safety switch goes bad and it gets worse and worse over time. It also could be that the spring on the kickstand is not holding the stand up all the way and it's getting weaker and weaker as time goes by and when you hit a bump, the stand goes down just enough to cut the ignition for a second then the bike bump starts itself back up.

Keep us in the loop.
 

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Enough lurking...

I bought my SP1 a few months ago and it ran perfect on the test ride. Got her home and on a proper ride she instantly started doing the same as you describe on aggressive accel or while hitting bumps.

I went through all electronics in the tail, cleaned with contact cleaner, followed up with dielectric grease, and never had a single problem since. Also make sure things are nice and secure with plenty of zip ties.

Oh, hi everyone!
 

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Thanks for the quick replies guys!

First off the bike is an electric nightmare, everything is taped off. I mean everything; the guy before me went to town trying to fix it, and just stopped soldering. I found a new connection tonight that looked shot and will solder tomorrow. I've gone through the tail end and checked everything over, and it looks good from what I can see. Unfortunately the snow will be barring me from testing it anytime soon =(
 

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To be more specific, the problem on mine seemed to be the connections with the ECU. It was also just sitting loose in the tail, free to bounce around. Nothing visually stood out but it was after messing with those connections and securing it down that the problem immediately cleared up.
 

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Discussion Starter #6
I actually did go through all the ECU connections and it looks surprisingly good, still all greased to boot. Going to keep on soldering all these iffy crimps and see if it clears up.
 

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So took the bike out in 32 degree weather today (dedication) to test it out and ran fine. Found one crimp that looked botched, soldered her and a few more up and seems to be running fine now. Hopefully stays that way for spring!
 

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If it is doing it when you hit a bump it is definitely electrical. First thing to check is the battery connections. Even if you already looked at them, check them again with a wrench to make 100% sure both are tight. Those are the culprit 19 times out of 20.

After that start looking for any exposed wires running up and down the subframe. You would be amazed how many times I have seen wires pinched by a hasty install of exhaust hanger brackets or subframe bolts etc.

Lastly the bank angle sensor can cause similar problems, but those cases are rare.
 

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If it is doing it when you hit a bump it is definitely electrical. First thing to check is the battery connections. Even if you already looked at them, check them again with a wrench to make 100% sure both are tight. Those are the culprit 19 times out of 20.

After that start looking for any exposed wires running up and down the subframe. You would be amazed how many times I have seen wires pinched by a hasty install of exhaust hanger brackets or subframe bolts etc.

Lastly the bank angle sensor can cause similar problems, but those cases are rare.
Not 9 times out of 10, not 99 times out of 100. 19 out of 20 times! :p :D
Good advice here; I've been my own victim of lowering the tank and pinching a wire or a vent hose...
 

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i had this happen once when i had put a battery besides a yuasa in the bike, the modified battery tray had been formed to hold a shorter battery, i put a taller one in, and it arched off the frame everytime i hit a bump. long story short...new rear wiring harness, 9/10 if it cuts out while riding its electrical, happy you got it figured out
 
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