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Discussion Starter #1
:BLAM:Just got my very own VN yeaterday (finally!!)
I don't have a shop manual yet sooooo I got a question about the forks.
This bike has the fork tubes slid up about 1 1/2" above the top clamp. Although I have done this on several bikes in the past I have never seen a stock bike like this. Should they be flush with the top clamp?
I also saw a thumb screw type cap on the forks legs. I took on off just to see what was in there and was shocked to nothing but a bolt for the cap!!!
What the hell is this?? How do you take the forks apart or at least change oil in them?
 

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Sparky!!!
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you can download the Kawasaki Service Manual for free HERE (be warned it is a large file and might take some time to DL if you are using Dial up... but well worth it...)

The forks you describe (without seeing pictures) sound like the air ride forks. and Yes they should be flush...but the rear might have been dropped... do you have a bracket similar to this:
 

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On His Lady Vulcan
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As Slim stated it should be flush, your PO lowered it is all,easy adjustment as youre well aware of I'm sure.
 

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Sparky!!!
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i lowered my rear, (11" progressive shocks) didnot change the forks. should the forks changed (lowered also)?
no, your forks can stay where they are at... you can lower the back with out lowering the front... but you can't lower the front with out lowering the rear... If you lower the front without lowering the rear it makes the bike very very unstable. Lowering the rear does change the steering geometry but not so much (as long as we are only talking an inch or two) as to cause drastic trail issues.
 

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Discussion Starter #7
No air forks. Just a rather cheap but ok plastic cap on a treaded bolt on the top of the fork tube.
I'm going to set them flush with the fork head.
I always set up my Flattrack bikes so the frame is level with the ground and this thing kinda slopes down in front a bit.
Dropping the front end doesn't make the bike handle bad (depending how much you drop it) it just makes it handle "quicker" which can be good in some cases.
Dropping the rear will make the bike handle slower making it not want to make sharp turns without effort, so to the guy that only lowered the back and not the front he may want to drop the front end a bit for better handling in the twisties.
All in all, I like the VN so far. I don't think I've ridin it more the 10 miles cause you guys have me so paraniod that I have been working for three days de-goating......drilling mufflers......installing a voltmeter etc.
 

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no, your forks can stay where they are at... you can lower the back with out lowering the front... but you can't lower the front with out lowering the rear... If you lower the front without lowering the rear it makes the bike very very unstable. Lowering the rear does change the steering geometry but not so much (as long as we are only talking an inch or two) as to cause drastic trail issues.
No air forks. Just a rather cheap but ok plastic cap on a treaded bolt on the top of the fork tube.
I'm going to set them flush with the fork head.
I always set up my Flattrack bikes so the frame is level with the ground and this thing kinda slopes down in front a bit.
Dropping the front end doesn't make the bike handle bad (depending how much you drop it) it just makes it handle "quicker" which can be good in some cases.
Dropping the rear will make the bike handle slower making it not want to make sharp turns without effort, so to the guy that only lowered the back and not the front he may want to drop the front end a bit for better handling in the twisties.
All in all, I like the VN so far. I don't think I've ridin it more the 10 miles cause you guys have me so paraniod that I have been working for three days de-goating......drilling mufflers......installing a voltmeter etc.
I wish somebody had told me about 4 bikes ago not to lower the front only,because that is the only way I could get them to handle the way I want them to turn in quickly and flick from side to side easily which is the effect that lowering the front has on handling,notice sportbikes have short forks and are high in the rear it helps to plant the front tire as well.
As in about everything else in life this is a compromise because you give up straight line stability and when taken to the extremes that sportbikes take the stance they add steering dampeneres and try to hold the head shaking or the death wobbles to a minimum.while all bikes are built for Joe Average there is usually some adjustability built in to most ,that if you know the rules and don't get in over your abilities,we should have no problems.
 

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Lowering the front only is dangerous. It decreases the rake and trail, which has a negative affect on stability. Sportbikes push the limit on rake and trail, which is what makes them handle so well (in the hands of a skilled and experienced sportbike rider), but they are very twitchy and unstable, which makes them unsuitable for inexperienced riders IMO. Also, Sportbikes have a far more sophisticated chassis and suspension, and a completely different riding position. A lot more attention is paid to their center of gravity and front/rear weight bias. Their frames are a lot stiffer and stronger.

Again, IMO, lowering just the front of a Vulcan 750 is just asking for it. I would not lower either end or both, because it decreases ground clearance, and the feeler things on my pegs are already ground off from dragging the pegs. A stock Vulcan 750 has enough ground clearance, considering what it is, but it doesn't have any to spare. Jerry.
 

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Premium Member
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I live and ride in eastern KY which a lot of the members on her can attest to is in the heart of the Appalachian mountains,I am no greenhorn and this not my first ride around the block,I have owned and ridden dual sports (back when we called them enduros,have had several bikes down to the frame and back to riding condition I have owened. MX bikes Standard street bikes full dress Harley's cb750 sohc hondas.Twq different rigid frame Harleys {One pan and one Knuckle)The dresser was a1972shovelhead,the firs cafe racers were built on stock frames ,which you pointed out led to stronger frames for the sport bikes of today,back up 15 years and look at the sport bike frame of the day and compare them to todays sportbike,big difference wouldn't you say,My number one riding bud and he's a 30 year bike veteran too rides a 2006CBRR 1000 RR and he doesn't have to wait on me in the twisties and he shows me no pity .I went with the bigger tiresand with thehuge amount of trail built into the vn's front end with it's leading axle, to say that dropping the front end 3/4 to 7/8 " is dangerous is just causing un justified fear in a young bikers mind.personally I ain't scared to lean mine over unless I have young riders with me who are on fast bikes and tend to overrun curves rather than lean it over and drive on through
 

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I still cannot recommend lowering a Vulcan 750. I too have ridden older sport bikes, and what we used to call "dual purpose" bikes. It was Honda that coined the term "dual sport" for their NX650, NX250, and NX125. It somehow caught on. I currently have a "dual purpose" bike, as well as an all out dirt bike. If you choose to do anything that affects the handling of your bike, you had better know what you are doing, because it is you that will have to deal with the consequences. While some people DO know what they are doing, telling your average rider to do something like that is irresponsible. You said it did make a difference in handling, and that "difference" might just get somebody killed.

I don't bring this up very often, because it usually generates a flood of negative posts. But I have also made what most people would consider a dangerous modification to my VN750. I removed the right front brake rotor and caliper. I felt that the front brakes on the Vulcan were just too touchy and easy to lock up. When I posted about that on here, the response was overwhelmingly negative. But, before ever riding in traffic that way, I tested it over and over again out on a deserted road. I practiced braking over and over again, from 100 mph all the way to a dead stop, keeping the front wheel on the verge of lockup all the way. I found that my stopping distances were unaffected, but the brake was much more controllable. I also intentionally locked up the front wheel a few times, for a fraction of a second, just to make sure it was possible. It took slightly more pressure on the lever, but it could still be locked up at will. Of course, locking up the front brake is not something you want to do, it was just to prove that I still had more than enough braking power.

Everybody also said that with only one front brake, the pads and rotor would wear out faster, and that the brake would get hot and fade a lot faster. That has not happened. How do I know? Because I made that modification over 25,000 miles ago. It has been tested in all kinds of riding, from canyon carving (which I find easy with the stock Vulcan suspension) to long distance riding, to heavy stop and go riding in 120 degree heat. The brake has performed flawlessly, the rotor still looks like new, and there is no excessive pad wear. It does not get hot, and it does not fade. Had I run into any issues with it, I would have immediately put the other brake back. But after 25,000 miles, I consider it proven. Many much larger and heavier bikes only have one front disc. So, it works for me. But would I recommend anybody else make this modification? No way. Why? Because it just might get someone seriously injured or killed, and I sure don't want to be responsible for that.


If what you did works for you, thats fine. But suggesting that it is completely safe, and suggesting that it is ok for someone else do it is a whole nother thing. Jerry.
 

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I still cannot recommend lowering a Vulcan 750. I too have ridden older sport bikes, and what we used to call "dual purpose" bikes. It was Honda that coined the term "dual sport" for their NX650, NX250, and NX125. It somehow caught on. I currently have a "dual purpose" bike, as well as an all out dirt bike. If you choose to do anything that affects the handling of your bike, you had better know what you are doing, because it is you that will have to deal with the consequences. While some people DO know what they are doing, telling your average rider to do something like that is irresponsible. You said it did make a difference in handling, and that "difference" might just get somebody killed.

I don't bring this up very often, because it usually generates a flood of negative posts. But I have also made what most people would consider a dangerous modification to my VN750. I removed the right front brake rotor and caliper. I felt that the front brakes on the Vulcan were just too touchy and easy to lock up. When I posted about that on here, the response was overwhelmingly negative. But, before ever riding in traffic that way, I tested it over and over again out on a deserted road. I practiced braking over and over again, from 100 mph all the way to a dead stop, keeping the front wheel on the verge of lockup all the way. I found that my stopping distances were unaffected, but the brake was much more controllable. I also intentionally locked up the front wheel a few times, for a fraction of a second, just to make sure it was possible. It took slightly more pressure on the lever, but it could still be locked up at will. Of course, locking up the front brake is not something you want to do, it was just to prove that I still had more than enough braking power.

Everybody also said that with only one front brake, the pads and rotor would wear out faster, and that the brake would get hot and fade a lot faster. That has not happened. How do I know? Because I made that modification over 25,000 miles ago. It has been tested in all kinds of riding, from canyon carving (which I find easy with the stock Vulcan suspension) to long distance riding, to heavy stop and go riding in 120 degree heat. The brake has performed flawlessly, the rotor still looks like new, and there is no excessive pad wear. It does not get hot, and it does not fade. Had I run into any issues with it, I would have immediately put the other brake back. But after 25,000 miles, I consider it proven. Many much larger and heavier bikes only have one front disc. So, it works for me. But would I recommend anybody else make this modification? No way. Why? Because it just might get someone seriously injured or killed, and I sure don't want to be responsible for that.


If what you did works for you, thats fine. But suggesting that it is completely safe, and suggesting that it is ok for someone else do it is a whole nother thing. Jerry.
Back up the bus Jerry and don't be puttin words in my mouth,I never once said that any thing is completely safe modified or not,the very act of riding a bike in it self is dangerous and have you seen what people have done to these things.If you back up a few posts tou will see that I stated if i said if people stayed within their abilities as in mechanical knowledge they should be fine ,ut to satisfy the billions of trial hungry lawyers and Jerry don't listen to anything I have said ,never modify or peronalize your bike without consulting Jerry and I will raise my front end back 3/4 of an inch to suit his riding style and so it will be more stable at speeds below ten MPH,I here by admit that it is a miracle that I have lived rto the ripe old age of 50 and would like to thank Jerry for saving my life and keeping me from killing countless others ,I am truly grateful in my little hillbilly heart.Consider the subject closed I know better than to argue with a man with one brake on the front ,JUst let me ask you did you ever consider a better front tire and a little lighter grip on that front lever before ,of all things ,modifying your motocycle?
 

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Sparky!!!
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Wait a sec JERRY... Hold up... didn't you say over and over again, that the wonderful guys in the Kawasaki design department knew what they were doing... and that if they made something a certain way there was a reason behind it. There are many things to tweek and adjust safely... and even the brakes can be moddified... but to remove one rotor on the front with out compensating for the loss of friction is bad juju... A single brake Rotor has been used in stock applications... but those rotors are a lot bigger than ours... Kawasaki used dual rotors on the front suspension to increase stopping friction. If you are wanting a softer lever... get a proportioning valve that would allow you to adjust the amount of fluid going down to the brakes. they sell them for automotive applications at JC WWhitney for less than 20 bucks... just put it inline with the master cylinder b4 the splitter. Bet hey... what do I know, I am just a 31 year old guy that has been building toys since i was a kid and who knows nothing about "Old School" mods.

As for the suspension rework... I would definantly not do any suspension modifications with out getting the proper knowledge first... when I posted that you can lower the back without the front, but not the front with out the back... I got this information from reading a lot on dropped cruisers and from doing research on building a true "Chopper".

But my point wasn't about weather or not you should jop just the front or not... but to have you look at the rear to see if it was dropped... also another subject... you didn't happen to get your bike off of eBay a few weeks ago did you?
 

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The Kawasaki guys did a lot of things right, but not everything. What about the cam chain tensioners? What about the swing arm covers that fall off? What about the joke they call a tool box lid? What about the fact that you have to pull the engine to replace the stator, when an aftermarket company (TOC) came up with a cover that allows you to replace the stator without pulling the engine? I guess Kawasaki wasn't smart enough to figure that one out. And why did they make the stator so weak in the first place? they put way to much brakes on it, and only half enough stator.


The fact is, that my brake mod has been proven in 25,000 miles of use. I have watched it very carefully. There have been no problems. Didn't you say your rotors were cracked? Mine isn't. In fact, it isn't worn or damaged at all. I checked it's thickness against the one I removed 25,000 miles ago, and they are the same. 25,000 miles, and no wear at all. Now, could this be done on other bikes? I have no idea. It did accomplish the improvement in brake feel that I was looking for, did not decrease braking performance or wear, and as for side benefits, now I only have to replace one set of brake pads, and they last just as long as they did with 2 discs. The front wheel looks a lot lighter and cleaner, and speaking of clean, it is now a whole lot easier to keep clean as well. But as I said, I would never suggest anybody else do this, even though I have proven that it works over the long term. I am somebody who understands bikes and knows how to ride them, and I also understand brakes. Still, while my calculations seemed to suggest that it would probably work, I spent a lot of time testing it under controlled conditions, to find out for sure if it would work, before riding it in traffic.

As for adding a proportioning valve, that just makes things more complicated. In case you haven't figured it out by now, I like LESS complicated, as long as it works.

I bought my bike new from a stealer dealer in 2002. They went out of business last year, because they could not get away with ripping people off in this economy. Jerry.
 

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Sparky!!!
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As for adding a proportioning valve, that just makes things more complicated. In case you haven't figured it out by now, I like LESS complicated, as long as it works.
Adding one simple vlave that works like a water faucit is complicated... I have used these simple devices over and over again to tune my breaks for every thing from my DD cars to Track and Strip racers, to adding 4 of them to my Rock Buggies for very tunable brake systems... but you are right... that would make things real complicated and be so much harder to do than removing a brake line, caliper, pads and rotor...

Ohh i lied about price...it's been a while since I ordered one... its 60 bucks
but here is what I am talking about.

if my brother can dial in one of these...any body can...
 

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Undercover Sportbiker
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Wow, we got really off track there for a bit.

New riders should not modify the stance of their bikes. Experienced riders should not modify the stance of their bikes, unless they are fully aware of what the modifications will do.

Lowered front = tighter steering at the cost of straight line high speed stability.
Lowered rear = better straight line high speed stability at the cost of handling (more turn in effort required)
Lowered front and rear equally = less ground clearance with no change in handling or stability

The question of safety has been strewssed a little too far IMO. Riding a bike is inherently unsafe. Modding your steering geometry is no less or more unsafe, provided you have done your research. The biggest safety factor in raising lowering bikes comes form people making changes and not understanidng the whole picture of how that change affects the total rideability of a bike. Again, this is JMO.

As far as how far up in the triples the frok tubes should be, that *should* be in the service manual. I would not trust the dealer to do it right. On my 650R, and on the 650r of every rider on the 650 forum, the fork legs were set flush with the top clamp. Look in the manual and it very clearly says to be at stock height, the legs must be 10MM above the top clamp. But the dealers were rolling them out the door set up wrong. Maybe someone can pull the spec up from the manual and post it.
 

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As an aside, I wonder if changing tire size affects the handling because we're raising and lowering the front or rear of the bike?
 

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Vintage bike addict
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Nearly every rider I've ever met has modded their bikes in some way. Whether it's just changing the position of the handle bars or adding floor boards. Any mods will affect handling either directly to the bike or by changing the riders position. The result can be good or bad from any mod. Ours is not to question the safety of a mod. That is the individual riders responsibility. Cautions are a good thing but lets leave it at that. If I want to stuff a Concours motor in the VN frame I'm not interested in possible center of gravity issues or whether the shocks can handle the extra weight. I'll only be interested in how to do it.
 
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