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Discussion Starter #1
I took the Vulcan out for my first ride on it today and I have a concern. Maybe.
I owned a '93 VN750 a few years ago and don't remember this symptom with that bike. The new one vibrates a lot, from the engine, such that everything in the mirrors is a blur. Constantly. No matter what speed or RPM. The mirrors are not stock, but seem quite sturdy. The engine sounds alright, maybe a little bit of cam chain noise which I will deal with soon, but that's it. My memory is garbage, so I may have experienced this with the last bike and just don't remember. But I thought it couldn't hurt to ask the experts what their thoughts are.

Opinions???
 

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I took the Vulcan out for my first ride on it today and I have a concern. Maybe.
I owned a '93 VN750 a few years ago and don't remember this symptom with that bike. The new one vibrates a lot, from the engine, such that everything in the mirrors is a blur. Constantly. No matter what speed or RPM. The mirrors are not stock, but seem quite sturdy. The engine sounds alright, maybe a little bit of cam chain noise which I will deal with soon, but that's it. My memory is garbage, so I may have experienced this with the last bike and just don't remember. But I thought it couldn't hurt to ask the experts what their thoughts are.

Opinions???
not normal,and have you checked the oil screen behind the drain plug for debris.and have you checked the motor mounts. the rubber dampeners part
 

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Discussion Starter #3
I have not checked either. i was told by PO that all maintenance was done recently and I shouldn't need to do anything.

Oil screen behind the drain plug... Do I need to drop the bottom pan to get at that? And why would that be the issue? (Because I'm not that familiar with these engines)

The engine mounts I will check. Should those be a problem already with an '04?
 

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Old Truck Junkie
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The oil drain is on the left side of the engine. It is a round plug with a 17mm bolt pattern made into it. It looks a bit like the rear end fill plug. Reach in to the drain hole and remove the screen. keep all parts in order for reinstallation.

Do not over tighten when going back with it.
 

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Discussion Starter #5
Does the oil need to be drained to do this?
On the center stand not the kickstand I assume?

I visually checked the motor mounts. To this untrained eye they look fine. No cracking, splitting, dry rot that I can see or feel. I did not check the torque values of the bolts. I do not have a torque wrench.
 

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Old Truck Junkie
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You can drain it on the side stand. Just keep all parts in order as they come out.
Inspect for plastic particles on the screen.
 

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What year is your new bike? Like you I went from an older (1994) VN750 to a newer (2004) one and found the newer one to vibrate a lot more. I hope you don't end up like I did and eventually discover it's a factory issue with the balancers that requires an engine pull to fix :(

As a side note, even after the balancers were fixed I still get noticeably more vibration through the frame and seat on my 2004 bike than on my older '94, though it's much much better than before.
 

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Given the age of your bike, it's not likely to be the rubber balance dampers disentegrating. They show up in chunks on the oil screen, but usually on much older bikes. You should always use the side drain to remove the oil and pull and check the screen every time.
 

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Discussion Starter #9
What year is your new bike? Like you I went from an older (1994) VN750 to a newer (2004) one and found the newer one to vibrate a lot more. I hope you don't end up like I did and eventually discover it's a factory issue with the balancers that requires an engine pull to fix :(

As a side note, even after the balancers were fixed I still get noticeably more vibration through the frame and seat on my 2004 bike than on my older '94, though it's much much better than before.
Aaaaarrrrrghhhhh....
Boy, this sounds like it to me. Would be nice to have another to compare them side by side.
I listened, I throttled it up multiple times, but I did not ride it before I bought it. PO did demo it for me. I do not think I would have noticed this anyway if I had ridden it. It has been almost 4 years since riding one of these before. Bike has 5400 miles on it. Question is, "Now what do I do?"
 

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Linkmeister Supreme
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Aaaaarrrrrghhhhh....
Boy, this sounds like it to me. Would be nice to have another to compare them side by side.
I listened, I throttled it up multiple times, but I did not ride it before I bought it. PO did demo it for me. I do not think I would have noticed this anyway if I had ridden it. It has been almost 4 years since riding one of these before. Bike has 5400 miles on it. Question is, "Now what do I do?"[/QUOTE]

Get a clean pan and drop the engine oil into it from the left side drain, and check the screen as mentioned before. Many times owners drain oil from the plug at the front bottom of the engine instead of properly from the side. If the PO did not check the screen, there may be rubber debris or aluminum shaving still in it. Checking that screen would be my first move.

If the oil is fresh just pour it back in the engine.
 

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The Professor
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3,147 Posts
I took the Vulcan out for my first ride on it today and I have a concern. Maybe.
I owned a '93 VN750 a few years ago and don't remember this symptom with that bike. The new one vibrates a lot, from the engine, such that everything in the mirrors is a blur. Constantly. No matter what speed or RPM. The mirrors are not stock, but seem quite sturdy. The engine sounds alright, maybe a little bit of cam chain noise which I will deal with soon, but that's it. My memory is garbage, so I may have experienced this with the last bike and just don't remember. But I thought it couldn't hurt to ask the experts what their thoughts are.

Opinions???
I have had several customers bikes with the same problem and it turned out to be the steering stem Spanner Nuts.

Place bike on the center stand and use a jack under the front of the engine to lift the front wheel off the ground. Below the upper tripple tree you will see the two spanner nuts.

Turn the bars all the way to the right, using a flat blade screwdriver and a hammer tap the lower nut at the front towards the right. Move the bars from left to right to check resistance, once the lower nut is tight enough tighten the upper lock nut.

Without knowing the history of the bike this may or may not be the problem but it is an easy fix if it is.

Around 2002-2004 there were a couple of factory issues:

1) Driveshaft improperly lubed

2) Left and right balancers not syncrinized to the balancer shaft causing excessive vibration

Not all bikes in this time frame were subject to the issues but some fell victim to poor quality control. :BLAM: There were not enough effected to consider a recall but I believe there was a TSB sent to the dealers.

A similar problem happened in the early ninety's, there is a small dot indented on the balancer and shaft on 92' and prior. In 93' they started useing a dash mark or hyphen, then painted a pink line to make syncronizing easier.

As you all know with all the assembly being done by a few people under the influience of alcohol, drugs, marriage, divorce, erectile dysfunction, mentapause, herpes, crabs, ADD, ADHD, PMS, PMDD WTF??? IBS, CMS, and soooooo on!!!!! or IJDGAF!!!!!!!!!!!!!! "I Just Don't Give A Fart"

CRAP HAPPENS!
 

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Discussion Starter #12
As you all know with all the assembly being done by the a few people under the influience of alcohol, drugs, marriage, divorce, erectile dysfunction, mentapause, herpes, crabs, ADD, ADHD, PMS, PMDD WTF??? IBS, CMS, and soooooo on!!!!! or IJDGAF!!!!!!!!!!!!!! "I Just Don't Give A Fart"
LOL! Thanks Lance! Been in the dumps all weekend about this problem. I needed a good Monday morning guffaw :rockon:
 

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Discussion Starter #13
Just checked the plugs - all a nice light brown. No oil.
Checked the air filter elements - both clean
Will check steering head spanner nut tomorrow, hopefully.
Will check the oil screen by the weekend. Work gets in the way.
Will try to get the carb sync checked by the weekend too. If I can find a place locally.

I did run it some after replacing the plugs. Idle set at 1000 - 1100 rpm. Held the throttle tight against the fixed collar, trying to hold a constant 2k rpm. Engine was steady for a while, then fluctuated up and down some, then rpm's increased to 4000 and I felt a pulling on the throttle grip pulling the rpm's up. I had to let go of it to get it back down. Same thing trying to hold 3k rpm.

Do I need a couple of tanks of Seafoam or some other fuel system cleaner?

I didn't feel any unusual vibration or shaking while running it at any rpm. From idle up to just over 4k. Just running it. No riding.

Should I ride this thing as is? At all?

Gotta get a shop manual too. Is there a favorite?
 

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Discussion Starter #14
This just flashed through my mind. Could my drive spline be skipping? Maybe it wasn't lubed properly and is worn to the point of skipping when a load is applied.

Am I way off base with this one?
 

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If you haven't checked your splines, you should do so sooner rather than later. I don't recall anyone whose splines failed reporting a vibration problem prior to failure, but that doesn't mean it couldn't happen.
 
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