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Discussion Starter #1 (Edited)
Well installing the stock airbox and ears was a giant step backwards! The bike spits and sputters. Will only run if the throttle is kept about 1/3 to ½ open and constantly twisted back and forth. Will not idle. Did my shooting carb cleaner up the drain blown out something or dislodge goo that now is stopping up something? I took the just installed ear covers and elements off to see if any effect, no change. I do see plastic caps covering vacum ports for the removed surge tank stuff. Could the PO have changed the mixture settings? I get the location from looking at photos in other threads. I also found a comment that says the mixture screws are factory set at 1 5/8 turn. I think i'll see what they are set at and reset at this spec and try again to start. I have ordered a Clymers but right now you guys and the foggy on line manual is the only reference I have. Thanks for the help so far and please keep it up.
3z
 

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and the Adventure Cycle
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If the PO had done the ear shave, they probably changed the jets too. You'll need to pull the carbs and go back to stock jets.
 

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Discussion Starter #3
I checked the jet on the front carb it is a 132 which i understand is stock. i did use a couple of gals of fresh gas and added about 3 oz of seaform. do I need to drain that out?
 

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That is the right main jet. There is also a Pilot jet which if I remeber right should be a 32 and a needle jet which should have no shims.

More than likely he did change the Air/Fuel mixture.

What you are describing sounds like a clogged pilot jet. The seafoam may clear it out with time.
 

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I was at our local American Auto parts store and talked to the Seafoam jobber guy when I picked up a can and asked how much was too much to mix in a tank of gas. He said use the whole can. I told him I had a motorcycle and it only held about 3 gallons of gas. He said it wouldn't hurt anything if I used the whole can and in fact I could run straight Seafoam like gas if I wanted to. So I dumped the whole can in...and no problem...done it twice now.

I'm not recommending anything here, just reporting what I was told and did. Kinda bet my carbs are real clean though. But if I thought I had a super clogged carb I'd probably use the whole can.
 

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Discussion Starter #6 (Edited)
I've been slowly adjusting the mixture screw on both carbs after screwing them in from 2 & 2 1/2 turns. I started by setting them both at 1 1/2 out and have moved them out to 1 3/4 and 2 out. Now it runs pretty smooth at 2 to 5 k rpms but still will not idle. Also will not rev above 5 k unless I snap the trottle down then back up quickly then it goes to about 7 but back fires from the rear cylinder and stalls back down to 5 k. I will pour the whole can of seafoam in the tank. I also believe I have a charging issue, but that will be a new thread.
thanks for the ideas and any more will be welcomed. 3z
 

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When my stator wires burnt, before I knew they did and my battery wasn't charging, I was riding home and noticed at 7K my engine began cutting out rather badly. That was because the battery was getting weak and couldn't handle the high RPMs...or so I determined. Overnight I fully charged the battery and there was no missing at the higher RPMs the next day.
 

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and the Adventure Cycle
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Now it runs pretty smooth at 2 to 5 k rpms but still will not idle. Also will not rev above 5 k unless I snap the trottle down then back up quickly then it goes to about 7 but back fires from the rear cylinder and stalls back down to 5 k.
Have you checked the choke cable to be sure it's working right?
 

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When my stator wires burnt, before I knew they did and my battery wasn't charging, I was riding home and noticed at 7K my engine began cutting out rather badly.
Excuse me for asking this, but do you guys think you are riding crotch rockets? Maybe I'm just becoming an old fuddydud, but I cringe when I get over 4k while riding. I watch the tach periodically, but have always been one to go by sound more than anything for shifting (call me old school). I mean, I realize redline is at 9k, but I can't imagine that it's too great on the engine to run high revs all the time - not to mention the loss in fuel economy. Am I all wet here?:smiley_th
 

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Discussion Starter #10
heck no, the last time I actually rode a bike at 7k rpm was 15 yrs ago and was on a flat hwy in west North Dakota. Nobody around for several hundred miles.
What this is about is trying to get my 89 project bike in resonable tune so I can ride it some while Im rehabing it. 3z
 

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Excuse me for asking this, but do you guys think you are riding crotch rockets? Maybe I'm just becoming an old fuddydud, but I cringe when I get over 4k while riding. I watch the tach periodically, but have always been one to go by sound more than anything for shifting (call me old school). I mean, I realize redline is at 9k, but I can't imagine that it's too great on the engine to run high revs all the time - not to mention the loss in fuel economy. Am I all wet here?:smiley_th
My normal cruising rpm is usually about 4.5-5k (65mph+). If passing I'll hit 6-7k rpm easily, but not for long.
On a nice, long, open stretch of road, I'll get it winding out as much as it'll go, but again, not for long (maybe a mile or two at most)
Remember, the Vulcan 750's engine is derived from the 750 engine for the Ninja and the high rpm's is what the engine was made for.
But good maintenance can't be forgotten if you want to continue to have fun like that!!:smiley_th

I am like you in going by sound for shifting. Same in any 4 wheeled manual shifting vehicle.
 

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Excuse me for asking this, but do you guys think you are riding crotch rockets? Maybe I'm just becoming an old fuddydud, but I cringe when I get over 4k while riding. I watch the tach periodically, but have always been one to go by sound more than anything for shifting (call me old school). I mean, I realize redline is at 9k, but I can't imagine that it's too great on the engine to run high revs all the time - not to mention the loss in fuel economy. Am I all wet here?:smiley_th
Ha ha, no...not too wet. I usually cruise somewhere between 55 and 70 mph. But I think it is good to wind the engine out every now and again when going through the gears. And it don't take long to get to 7k, just be sure you got enough road ahead. :)

But really, I bought the '85 with 9200 miles on it. Wasn't long I noticed I was low on oil...thinking a quart of oil every 600 miles???? Not knowing what kind of oil the PO used I changed to 15W 40 Rotella...extra engine cleaning oil, or so it said. Bike sat up most of its life and I wondered if engine was dirty or if it was broken in right, so with the extra cleaning oil I thought some fast and high RPMs now and again might help clean and seat the rings better. With the new oil in the bike and an extra quart I've got 1200 miles and a little left in the quart...so, maybe 1500 miles to a quart of oil. Think I'll try some Syn 20W 50 next time if I can find any.

So yeah, I usually ride easy. But at least twice a season I like to gently wind it out through the gears. I never have found enough straight highway where I live to get to 7k in 5th gear yet...I think little wings pop out if you do. :)
 

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Discussion Starter #14
thread has drifted away from topic... sorry

thread has drifted away from topic...:zzz::zzz:
 
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