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Discussion Starter #1
I'm trying to track down the reason that this '01' vulcan won't run. As long as I hold the starter button and the choke is on the thing will fire enough to warm the pipes but, as soon as I release the starter it stops.

I thought it was carb related so I took them out and checked the jets. the pilots were kinda dirty so I cleaned them. I also found that the float neddle on the rear carb was stuck closed. I freed it up and put the carbs back on.

Problem still there.

Here's what I've checked since;

compression 160psi front/165psi rear

primary winding 2.2ohm front/2.3ohm rear

secondary winding 22,100ohm front/22,300ohm rear

sparkplug caps front shortcap 4590ohm/front long cap 17,600ohm, rear short cap infin/rear long cap 4570ohm

p/u coils front 449ohm/rear 455ohm

The only things out of spec according to the book are the sparkplug caps which are listed to be between 3.75-6.25ohm. I know there are some misprints in the manual. Are these figures correct? I checked some plugcaps that I have lying around and they ohm'd out at 10,000ohms.

Does anyone have the right ohm's for the plugcaps?

Thanks
Mike
 

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Discussion Starter #2
Hey,
Thanks for all the help:smiley_th. I found what the resistance of the plugcaps are. It is 5,000ohm. The Clymers is not correct as far as plugcap resistance(pg.343 table3). The short cap # LD05F, 05 for 5000ohm. The long cap # XD05F. I ordered 4 new caps I'll update when I put them on. I hope this is the problem
 

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Discussion Starter #3
I got new sparkplug caps and put them on; no change

I checked the spark box with both analog and digital ohm meters. They didn't have the same readings, but the analog matched the Clymer's and the digital matched a chart I found on this forum. WUWT?

It had Champion iridiums in it I changed them out for NGK DP-7's. They made nice fat blue spark but, the bike still won't start just backfires out the carbs every so often. It acts like it's out of time.

I don't know if the spark box has transistors in it that control the timing. I don't like to think that I need to get a used spark box. They're alot of money and if that doesn't cure the problem they can't be returned.

The only other thing that can affect the ignition timing would be the rotor shifting a little throwing the raised nub off a few drgrees.
 

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'03 VN750 "Rosie"
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I'm not sure how to help you, but what do you mean by spark plug "caps"? I just changed my plugs and there are knobs on the tip that have to be removed before the wires are connected. They are threaded and screw off and the boot (on the spark plug wire) just zips down over the bare threads.
 

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Discussion Starter #6
I checked the carbs again. The float hieght was within spec and the petcock has good flow. The plugs start out dry and after trying to start it the plugs are wet.

You'd think there'd be a happy medium between dry and wet where it would start.

I'm going to tear into the motor next.
 

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Where in upstate are you located? I'm in Rochester.... and I have a spare box if you wanna try that....
 

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Discussion Starter #8
Hey, Thanks for the offer Dariv. But I think the spark box is OK. When I took the rotor off the halfmoon key was sheared off. I'm going to get a new halfmoon and rotor bolt and try that.

I'm south of Utica just off US 20.
 

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Jes so all of ya know...stock Kawi plug caps (the older ones anyway), have a built-in resistor...looks like a buss fuse, but gotta be a resistor...guessing they added them for those who couldnt get the "R" plugs...I replaced mine with a piece of cut bolt....screw AM radio anyway....well, the band that the public has...

If you look into the plug end, you'll see a brass hollow bolt with a slotted tip...it unscrews...never seen this info posted here before...found it on my own when I switched to car ignition wires...
 

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Sparky!!!
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one other thing... I had a similar issue (a lot).. and found it to be bad grounds with a week battery. it would turn over just fine.. and if I "jumped" from a car battery, Red to battery terminal, and ground to MC Frame, I could keep the bike running. Might try to see if that makes your bike run, if so... then look at the grounds/and battery cables.
 

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Discussion Starter #11
Well I got the halfmoon key in and buttoned things up. It started right up but, it ran real sh*ty. Smelled real rich but I had put alot of seafoam in it over the last month or so.

The next morning I took a closer look at things. It was only running on the front. The rear was cold so I took out the short plug and it was soaked gas. When I hit the starter gas shot out of the plug hole, then the spark from the grounded plug set the gas on fire(fire&steel for real) no fire extinguisher had to blow it out, thanks to all the practice I've had blowing out birthday candles.

So the float needle in the rear carb was stuck open. Earlier the same float was stuck closed. There was corrosion on the vanes on the needle and in the seat. A small file tookcare of the needle and some emery cloth rolled up into a little tube cleaned up the seat.

I took the front carb apart and cleaned that float too. I had trouble getting the float pin out. had to drill a 1/16th hole under the pin to get an awl in to pry the pin out.

We did the ear shave and drilled the pilot jets with the second smallest torch tip cleaner.

I was able to get the carbs in with both carb boots on the heads.

It started first crank and settled into an idle. Both pipes got hotbut, it was running rich. We started out with the pilot needles set at 2.5 turns out and turned them in 1.25 so there out 0.75 turns

I got it idling good @ about 1100rpm with standard NGK-7's then switched back to the Champion iridium's. The idle jumped up to 2100rpm. More efficient burn?

Well Vulcanstein is alive and rolling Long Live Vulcanstein
 
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