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After riding a 1994 VN750 for a year I loved it so much I wanted to get as new a bike as possible (given that it's not made any more), then pass on the '94 bike to a friend of mine.

Back in March, I eagerly jumped on the chance to buy a 2004 VN750 with 555 miles on it. I got it from the second or third owner of the bike, who had had the bike for a year and a half but only put on less than 100 miles on it. He had ridden a different VN750 for 8+ years ("into its grave") and got this low-mileage one as a used bike on eBay from some guy in Wisconsin to replace it, but preferred to ride his newer toy, a BMW R1200RS, so was selling the Vulcan. That "guy in Wisconsin" in turn had gotten it as a starter bike but mostly it sat in his garage.

As soon as I got it, I did or had done the usual "new to me" bike maintenance: oil, filter, brake fluid changes, carb cleaning, new MF battery, spark plugs, etc. But even so, I've discovered a few things wrong with it that are not problems on the much older '94 bike.

1 - Vibration issues. My '94 bike is very smooth, I can rev it to 5K and hear the engine purr/roar but not feel a thing. My key chain can rest on top of the "Kawasaki" name on the bars as quiet as anything.

My '04 bike used to buzz and rattle the bars as soon as I took it past 3K RPM. The key chain danced and rattled, my feet and hands tingled. I had the carbs cleaned at a dealership and it still happened. The dealer told me I needed new tires (which was true, after 5-6 years of sitting around) but that didn't help the vibration. I looked up the locations of the frame bolts in the Clymer and the Kawasaki service manual, and tightened them up as much as I could, which helped a lot but it was still there.

Turns out the rubber mounts on the fuel tank and engine bracket have shrunk and/or rotted, contributing a lot to the vibration. There's still some left, though, and I feel like it's ridiculous that a bike 10 years older could feel smoother than it does.

2 - Fuel tank leak. I would always smell gas around my bike and couldn't figure out why. Finally I took the tank off and checked the bottom. I couldn't see any obvious hole or crack, but if I left the tank on some styrofoam, after a few hours there'd be holes in the styrofoam from gasoline dropping onto it (which burns a hole it the stuff). I ended up using two entire tubes of a Permatex epoxy recommended by lance328 to cover up every part of the seam where the center tank mounting bolt is welded onto the tank to get it to go away (I hope).

My '94 bike suffered from rust INSIDE the tank (which I recently cleaned out with acid), but shows no sign of leaking. Why would a bike with so few miles on it have a weak tank?

It occured to me to worry that, as much of its life had been spent sitting in various garages (I hope -- if not covered in the street), perhaps the critical first maintenance (at 600 miles) was never done over a 5 or more year period. And also to wonder, what is the break-in period on the bike, and what happens if it was basically never really broken in? Is that possible?
 

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Why would a bike with so few miles on it have a weak tank?

And also to wonder, what is the break-in period on the bike, and what happens if it was basically never really broken in?

Is that possible?
Quickly editing al that you wrote, I found the above questions.

Any tank new or old can have a bad weld. Age has not alot to do with it.

The first service on the bike really is nothing more than an oil and filter change.Thats about it for almost every bike made. Really, what is there to fix at 600 miles?
If the bike was not "broken in" yet because it only has 555 miles (I think 600 miles is the first "Break in" limit) all you really need to do is ride the thing and don't wind it out to redline.... for awhile.

"Break in" is a contraversial area, many suggest riding a bike like you stole the minute you wheel it off the showroom.

No two bikes seem to be the same and again, age is not always the deciding factor. Take the bike change the oil and filter, fill it with fresh gas and bit of seafoam and just ride the damn thing. If one vibrates more than the other there may be many causes, but that does not mean the motor itself is defective.

Again not sure what you are trying to find out here.


KM
 

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Discussion Starter #3
Any tank new or old can have a bad weld. Age has not alot to do with it.
...
The first service on the bike really is nothing more than an oil and filter change. ... If the bike was not "broken in" yet because it only has 555 miles (I think 600 miles is the first "Break in" limit) all you really need to do is ride the thing and don't wind it out to redline.... for awhile.

"Break in" is a contraversial area, many suggest riding a bike like you stole the minute you wheel it off the showroom.

No two bikes seem to be the same and again, age is not always the deciding factor.
I guess that was a bit rambly, eh? To summarize, I was wondering if getting a very low mileage but still 5+ year old bike may not have been a mixed blessing. In particular, if the fact that the bike was not ridden to 600 miles (the break-in and first maintenance limit) until I got it 5+ years after it rolled off the dealership floor could have any long term implications in areas such as engine vibration, where I was puzzled why it would seem worse off than a bike 10 years its senior. Or anything else I haven't run into yet.

Realistically, the tank having a bad weld and the rubber mounts being more brittle or shrunken is more likely a factor either of "from the factory" variation or in how it was stored for those long stretches of idle time, it can't have anything to do with not being broken in per se.

If the answer is basically "what a stupid question", that's fine with me :)
 

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No question is stupid if you don't know the answer, silly maybe, but that's subjective.

I went over this with Glenn and his thirty two hundred dollar '85.

Low miles is always a good thing, but in motorcycles you have to ask yourself if the bike has what seems to be really really low miles and the bike is several years old, that can only mean the bike was not ridden alot. This can be a problem in itself, especialy with the Vulcan, which does not like to sit around.

The tiny tank does mean that condensation will mix with less fuel than a bike with a 6 gallon tank, and if the bike sat alot , the carbs might be an issue. (As we have seen many times here)

How a bike is broken in is likely not as important as how well it was cared for. Thats why I said age is not always a factor. I know my all ways garaged never really ridden in the rain and pampered like religous artifact 2002 750 was in better shape than a few 2005 models I have seen.

Having bad tank mounts likely added more stress to a weld not designed to work with out them, and yes, some bike just seem to run smoother than others..hard to say what the cause is, but I do know in general, that a motor with 10,000 miles on it runs better than one with 200 miles on it.
"Break in" does not just end at that first 1200 mile mark. Engines , if pampered too much, might take alot longer to "break in" or as I say " Finally get into a groove".
And you also have to figure in what is called the "lemon factor" or the "Friday unit"... that the bike just might not have been assembled as carefully as it should have been and may just be a bit "special".

The deal here is if the bike runs rougher there may be absoultly nothing you can do to make it better. New engine mounts aside, if the motor itself vibrates alot more than most, it will wear through those new mounts faster, and you will be back at the begining.

"If your eye doth offend ye, pluck it out" Which means if the bike is that annoying for you to ride, sell it off and find another one. No one will blame you, why waste time and money if you don't have to?

KM
 

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Hey robardin, here is a link to motoman and his break in method, which has yielded race bikes with significantly more power and longevity than bikes broken in according to factory directions.

http://www.mototuneusa.com/break_in_secrets.htm

I have spent the best part of two days this week reading his website. His method is controversial and many who have watched his success in building winning engines and bikes, will not accept what they see, even when he tears an engine down after a winning championship race, to prove that it is a basicly stock engine. It is still in better shape than identical engines broke in as specified by the maker.
 

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Hey robardin, here is a link to motoman and his break in method, which has yielded race bikes with significantly more power and longevity than bikes broken in according to factory directions.
There are two basic flaws with motomans method.

Breaking in a motor is not just about pistons. There are valves, valve guides, camchain gears, transmission gears, shifter forks, and a host of bearing surfaces that have to "wear in".


Secondly, if you really read the "factory directions" you will notice they say nothing about running the bike hard or putting a load on the engine...they simply say "not to run the bike over a specific rpm level" for certain amount of time.

Many believe that means not to , for example, run the bike over 5000 rpms at all until for the first 500 miles. That is not however what the factory is telling you. What they are saying is not to run the bike over 5000 rpms for "an extended amount of time" they quite specificly say to vary your engine speeds as much as you can, but nowhere ever have I read them to say DO NOT OPPERATE THE ENGINE OVER XXXXX RPMS AT ANYTIME. According to a tech that worked for Honda, this area is the most misunderstood bit of info found in the owners manual. Folks get a bit paranoid about it and end up being too gentle to their bike for those break in miles.


That being the problem, it is easy to understand why some think there is a huge difference in motomans method, but if you look at it, you will see that motomans advice is in fact not that different than what the factory actualy reccomends.

Motomans idea does not say redline the bike, it just says accellerate hard and decellerate hard. No where in my owners manual does it say I shouldn't do this... all it basicly says is just not to let the bike run for long periods at the same rpm.

What also tends to happen is riders do not read motomans advice carefully either, and end up running their bike at high rpms thinking that is what they should do.

So when I said break in was a contraversial subject, it is only do to folks that misunderstand it. motoman included...as it is clear he doesn't really understand the "factory directions" either.



KM
 

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Discussion Starter #7
...yes, some bike just seem to run smoother than others..hard to say what the cause is, but I do know in general, that a motor with 10,000 miles on it runs better than one with 200 miles on it.
"Break in" does not just end at that first 1200 mile mark. Engines , if pampered too much, might take alot longer to "break in" or as I say "Finally get into a groove".
Well that's kinda what I was hoping to hear. I'm just about to roll it over 3,000 miles, having put about 2,500 miles on since mid-April, and vibration and fuel leaks aside, the engine is starting to feel and sound more... buttery. And yes, I'm riding it pretty hard :)
 
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