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Discussion Starter #1
I have had the bike in and out of the shop for over a year now. Several mechanics have said the alternator is the problem that is causing the power to cut on and off during riding, and even at idle. The voltage with the original alternator there were spikes showing over 60 volts. I replaced that alternator with a used own which I had purchased from ebay. Now the readings spike as hi as 16 and once hit 18. I am getting so frustrated and have spent so much money on this bike. I love the F4 but I am about to give up. Does anyone have any answers to what else this might be?! This is killing me!
 

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I'm not sure 16 volts is something to worry about, but I think 18 is. The alternator has an internal regulator. The alternator man is Jason Chapin. He's had his in and out dozens of times. Send him a pm, perhaps he might have some ideas.
 

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Your message sounds a bit confusing, you mention power cutting in and out, by this I take it the bike randomly turns itself off or dies, cut's out right ?

When it cuts out, does the dash go dead too ? How do you restart the bike, I mean what do you have to do to get it going again ?
Have you had to replace any blown fuses ?

Sorry about all the questions, but in all honesty, I can't see a alternator problem letting the bike cut out like that without causing other problems too.

Have you checked things like wiring connections and side-stand switch etc ?
 

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Discussion Starter #4
Thank you guys, Donsy, I got a new throttle position sensor, injectors, fuel pump. filter, and neutral switch as the first mechanic told me he thought it was fueling. Which was bullshit. depending on the situation the battery light would flicker on and off usually more after I would rev the engine ( as the rpms decreased) . It does not want to idle it stalls out. The fuses would blow and I have replaced them i bought a battery last year and i had to be another this year. I just replaced the alternator with another used one from ebay and still having the same effect, however the spikes do not seem to be as great.
 

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You're going to need to start chasing wires down and looking for failed insulation and or wear marks. Yep, that means pulling back all the sheathing/wrapping. While at it double check all connections for corrosion. Its all but impossible to properly diagnose an electrical problem over the net but it sure sounds like a grounding/shorting out issue based on what you've reported. Also, don't forget to check your CPS to be in spec and wiring to be ok.

Could be an off chance you got another bad stator/alternator. Its easy to rule out if you just take it to a shop that rebuilds them who would have the equipment to bench test the unit by itself. Most would do it for free, but even if they don't it shouldn't cost very much.
 

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You're going to need to start chasing wires down and looking for failed insulation and or wear marks. Yep, that means pulling back all the sheathing/wrapping. While at it double check all connections for corrosion. Its all but impossible to properly diagnose an electrical problem over the net but it sure sounds like a grounding/shorting out issue based on what you've reported. Also, don't forget to check your CPS to be in spec and wiring to be ok.

Could be an off chance you got another bad stator/alternator. Its easy to rule out if you just take it to a shop that rebuilds them who would have the equipment to bench test the unit by itself. Most would do it for free, but even if they don't it shouldn't cost very much.
+10.....
off to the alternator shop you go:drummer:
 
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