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 Post subject: Need electrical help...I'm dying here!!!
PostPosted: Fri Oct 13, 2017 3:03 pm 
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Joined: Wed Jul 12, 2017 3:34 pm
Posts: 71
Location: Virginia
Bike was running great but needed to fix first gear in the transmission.

Pulled stator to get the transmission cassette out, replaced the gear cluster and installed new shift forks. put everything back together.

start the bike and the lower cylinders are running fine but the top cylinders are missing and farting and weak exhaust output.

new plugs....same
swapped coils....same
swapped orange and black wires from upper coil to lower coil and vice versa.....same
different plug wires on upper cylinder....same
Ohms on pick up leads checked out ok
Ohms on windings were alittle high, but barely
has a 4 degree key on the crank, switched it forwards and backwards.....same
tried a backup cdi.....same

I'm out of options and miserably frustrated....... Any magical suggestions???


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Fri Oct 13, 2017 4:09 pm 
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Joined: Thu Nov 17, 2005 11:12 am
Posts: 371
Location: Leicester, NC
Did you paint anything while the motor was out? You may have a bad ground. Try running a dedicated ground wire from the stator cover to the upper and lower coils.

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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Fri Oct 13, 2017 5:17 pm 
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Joined: Mon Sep 14, 2015 12:30 pm
Posts: 618
Location: Bay Area. CA.
How long was the bike sitting, I would clean the carbs out, They might be gummed up from sitting, The ethanol is awful if you leave the bike sitting any length of time with ethanol blocker in the gas..


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Fri Oct 13, 2017 5:48 pm 
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Joined: Wed Jul 12, 2017 3:34 pm
Posts: 71
Location: Virginia
tacky1 wrote:
How long was the bike sitting, I would clean the carbs out, They might be gummed up from sitting, The ethanol is awful if you leave the bike sitting any length of time with ethanol blocker in the gas..


The bike was only down three days and ran perfect before pulling the transmission.


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Fri Oct 13, 2017 6:19 pm 
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Joined: Tue Sep 08, 2015 5:27 pm
Posts: 50
Location: Royston, UK
As you pulled the transmission the clutch must have been off. Crazy question but have you double checked the cranks are in phase. The front crank has the rotor on it so would not be effected, not so with the rear crank and one gear tooth out could give the problems you describe.

If above OK try the carbs.

Regards
Paul


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Fri Oct 13, 2017 7:38 pm 
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Joined: Wed Jul 12, 2017 3:34 pm
Posts: 71
Location: Virginia
Paulrs wrote:
As you pulled the transmission the clutch must have been off. Crazy question but have you double checked the cranks are in phase. The front crank has the rotor on it so would not be effected, not so with the rear crank and one gear tooth out could give the problems you describe.

If above OK try the carbs.

Regards
Paul


To pull the trans cassette you only take off the two nylon gears and the kick start gear, so both cranks never get changed or touched... These are on the clutch side of the bike.


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Sat Oct 14, 2017 6:20 pm 
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Joined: Wed Jul 12, 2017 3:34 pm
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Location: Virginia
Problem solved.... With the clutch basket off one crank can turn freely.... and I moved mine, unknowingly. Why I decided to check it I'll never know, but it was off....set it back where it should have been and it fired on the second kick and sounds wonderful.....


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Sat Oct 14, 2017 6:23 pm 
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Joined: Wed Jul 12, 2017 3:34 pm
Posts: 71
Location: Virginia
Paulrs wrote:
As you pulled the transmission the clutch must have been off. Crazy question but have you double checked the cranks are in phase. The front crank has the rotor on it so would not be effected, not so with the rear crank and one gear tooth out could give the problems you describe.

If above OK try the carbs.

Regards
Paul


You were right....I didn't realize it until I rechecked....I never would have believed it!!!


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Sun Oct 15, 2017 3:50 am 
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Joined: Tue Jul 19, 2011 7:49 pm
Posts: 246
Location: Toulouse France
So, you mean that you swapped plugs, coils, wires, CDI, ... without checking if you had sparks ?


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Sun Oct 15, 2017 11:32 pm 
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Joined: Wed Jul 12, 2017 3:34 pm
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Location: Virginia
No, I had spark...that's what was driving me crazy..... It missed badly, popped and weak exhaust pressure. The rear cylinders were firing when the pistons were NOT at TDC. The crank turned out of time when I had the clutch basket off...


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Sun Oct 15, 2017 11:45 pm 
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Location: Bay Area. CA.
thumper580 wrote:
Paulrs wrote:
As you pulled the transmission the clutch must have been off. Crazy question but have you double checked the cranks are in phase. The front crank has the rotor on it so would not be effected, not so with the rear crank and one gear tooth out could give the problems you describe.

If above OK try the carbs.

Regards
Paul


To pull the trans cassette you only take off the two nylon gears and the kick start gear, so both cranks never get changed or touched... These are on the clutch side of the bike.


You have to pull the clutch to get the gearbox out, The clutch main nut is on the end of the gearbox shaft, Are you sure the cranks are timed correctly

EDIT: Sorry, I see you fixed the prob


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Mon Oct 16, 2017 4:07 am 
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Location: Toulouse France
thumper580 wrote:
No, I had spark...that's what was driving me crazy..... It missed badly, popped and weak exhaust pressure. The rear cylinders were firing when the pistons were NOT at TDC. The crank turned out of time when I had the clutch basket off...


Yes, but you didn't say it and we thought that you hadn't sparks on them.
The only thing you said is that you swapped nearly everything in the rear cylinders ignition and, in fact, all that was useless cause ignition was good.
Never mind, you found it.


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 Post subject: Re: Need electrical help...I'm dying here!!!
PostPosted: Mon Oct 16, 2017 3:25 pm 
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Joined: Thu Mar 09, 2006 12:54 pm
Posts: 254
Location: Germany
phildu31 wrote:
So, you mean that you swapped plugs, coils, wires, CDI, ... without checking if you had sparks ?


Which is completely harmless as the RD500 always fires all four plugs at once. So swapping them all around will always work.

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