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Discussion Starter #1 (Edited)
I've found that the front brakes on my 1994 VN750 are pretty grabby. I only have to pull the lever in about 1/4 of the way for a lot of braking, by halfway it's like fully locked. I've bled out the brake fluid but it didn't help. It's been like this for a while - probably since the bike was knocked over while parked in the street by assailants unknown about a year ago (who then picked the bike up at least).

I mentioned this last year to a dealer mechanic when I brought it in for a carb cleaning after it got gummed up from rust in the tank and he said, "seems normal to me". (Of course this is the same dealer mechanic who said "seems normal to me" about my 2004 VN750's vibration issues that turned out to be a factory-misinstalled balancer, where the vibration actually was bad enough that the fuel tank had developed a hairline crack near the mounting point to the frame...)

I did some Googling on this topic and found this on an H-D board: I Had to replace the Master Cylinder the inside walls were out of round (had a low spot on one side). wouldn't let the brake back bleed in to the cylinder.

Huh, that hadn't occurred to me. Does that ring true? The bike fell onto its left side, where I replaced the bent clutch lever and then straightened the fork, so I didn't think about why the right side of the bike might have any problems, but maybe it was actually hit on the master cylinder by whatever car or truck clipped it to knock it over.

How would I test for this, and how hard is it to replace the Master Cylinder? (Bleeding the brakes is kind of a time-consuming pain as it is.)
 

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Well, Robardin. Myself, i would spray the surfaces with brake clean and make sure its not contaminated...and inspect the pads if possible. I put speed bleeders on my bike so its easier to bleed them...i put all new brake fluid in mine ...it was easy just put a tube on the nipple and drain the excess into a beer bottle. I would just make sure its good and flushed and replenish with proper stuff. There is a thread on here somewhere about it. Dont forget to tie the brake lever down overnight...helps get the air out.
 

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and the Adventure Cycle
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Ya sure you don't have too much fluid in the master cylinder?
Also could be cheaper brake pads causing them to grab.
Have you measured the brake discs? Don't know if those being below safe levels would cause issues, but wouldn't hurt to check.
 

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Undercover Sportbiker
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I'm all for the "too much fluid" theory myself. That will give you exactly what you are experiencing assuming nothing is actually broken or worn out. Bonus - it's the easiest thig to check via the sight glass.
 

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Discussion Starter #5
Well the brake fluid level looks OK based on the level sighting on the master cylinder - it's right at the LOWER line in fact, if I drain significant amounts it'll dip below that... Maybe after a trip to get some DOT 4 at AutoZone tomorrow.
 

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Linkmeister Supreme
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I've found that the front brakes on my 1994 VN750 are pretty grabby. I only have to pull the lever in about 1/4 of the way for a lot of braking, by halfway it's like fully locked. I've bled out the brake fluid but it didn't help. It's been like this for a while - probably since the bike was knocked over while parked in the street by assailants unknown about a year ago (who then picked the bike up at least).
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OK this is just happening since the bike was knocked over, and the grabby brake is the primary problem.

I tend to agree with Kimmerling about cleaning the disc. I would also pull the calipers and take a good look at the brake pads. You can try cleaning them, but if they are contaminated with brake fluid or oil, etc., you will probably have to replace them to eliminate the grabby condition.

I don`t think any excess amount of fluid in the reservoir will affect hydraulic pressure developed by pulling the brake lever, which acts against a master piston in the master cylinder. The fluid in the reservoir is not under this pressure.

Is the distance your brake lever moves now a problem? Has it changed since the tip over? I just checked my brake, and it seems to move about 1/4 of the way to start feeling significant resistance, and 1/2 way would be a lockup. Yours seem to be about right.
 

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Discussion Starter #7
Is the distance your brake lever moves now a problem? Has it changed since the tip over? I just checked my brake, and it seems to move about 1/4 of the way to start feeling significant resistance, and 1/2 way would be a lockup. Yours seem to be about right.
OK then I guess it's my 2004 bike that has overly soft brakes. On that bike, I have to pull about halfway to feel a lot of resistance and pretty much nearly all the way to the grip to get a lockup.
 

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CWO3 Navy (Retired)
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I have a couple posts on here about replacing the master cylinder and brake bleeding. I would be rebuilding the calipers, especially if it's never been done. The fluid turns to gel over the years and if you haven't taken the calipers apart I bet you find a gel-like substance in there. I rebuilt mine, it's extremely easy to do. I bought new pistons and seals at cheapcycleparts.com (where I bought all my VN750 parts). Then I'd rebuild the master cylinder and pay particular attention to that ultra tiny hole in the shallow dimple in the master cyclinder; this is thre return hole and if it gets plugged you will have problems. Blow everything out with compressed air, clean real well with fresh brake fluid and put everything back together. Get yourself a set of Speed Bleeders and you can bleed the wheel cylinders yourself, bleeding the master cylinder is also easy, the Clymers Manual has a good section and instruction on it (or look up one of my earlier posts). Good luck - don't mess around second guessing the brakes - tear it down and rebuild them, they are 16 years old and need a good cleaning.
 

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Undercover Sportbiker
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I can't believe I missed it first time around. Have you checked your fork alignment? If it happended since a knock over, maybe the forks are just a tad off, causing some binding?
 

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First of all, this is just my opinion, not advice, so please don't take it that way. I noticed the front brake was grabby from the first day I bought my brand new '93 Vulcan 750, and it stayed that way for over 80,000 miles, and several sets of brake pads, cleanings, and fluid changes. Different tires made no difference. I decided that the Vulcan 750 simply had too much front brakes for it's size.


When I bought my '02, it felt the same way. Just barely squeeze the brake lever, and it wanted to lock the front wheel. Very touchy. Rear brakes on both bikes were fine. Finally after putting about 20,000 miles on the '02, I decided to try something. I completely removed the left front caliper and hose. The brake suddenly felt normal, and worked fine. I did extensive testing at a large open area free of traffic, including controlled stops from an indicated 100 mph with the front wheel held on the verge of lockup. It worked fine every time, and stopping distances were uneffected. I went ahead and removed the rotor, and have since put over 25,000 miles on it, under all kinds of conditions, including a lot of stop and go city riding, mountain riding, and long trips. The brakes have performed flawlessly. They do not overheat, they do not fade, the pads do not wear out any faster (and now the front brake only requires one set of pads) there has been no noticeable rotor wear, I have been in a lot of close calls since then, and the brakes worked perfectly every time, holding the wheel right at lockup, where it would have locked up before, with both discs.


Quite simply, I think dual front discs are overkill on a bike the size and weight of the Vulcan, though they could have been made less touchy. Many much larger bikes have less front brake swept area than the Vulcan 750 does, and stop just fine.


Now, under no circumstances am I even suggesting anyone do this, only that it has worked fine for me, and has been proven safe (IMO) by 25,000 miles of day to day use. As with any other modification, if you do it, you do it at your own risk. But I can't see how what I did is any more dangerous than a brake that almost locks the wheel (not a good thing) every time you touch it. Jerry.
 

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I think what Jerry touched on is basicly true, and my thinking here whoever knocked your bike over appearently also knocked the air out of your brake hoses and your bike is working like it is supposed too.

The key to using the brakes is learning how much pressure you really need. If you are used to squishy/mushy brakes , and then jump on a bike with "touchy brakes" you will of course feel something is wrong.


I can haul my bike down to a stop with one finger on the front lever. This is how it should work , it is a matter of learning what effort is needed.

True "grabby" brakes seem to lock up at different lever pressures.....meaning sometime they grab more with the same applied pressure.

Brakes that are working right should lock the wheel with the same effort every time. Your speed of course makes a difference here, as it is easier to lock the wheel at parking lot speeds as opposed to normal road speeds.

To me the duel discs on the Vulcan were the best selling point. It does of course take some time to learn the various limits of braking pressue for each given speed and road condition. My thinking is that the brakes on the bike are not "too much" , but simply too efficiant for some riders. Given the weakass rear brake, I feel that this is really a good thing and would not in any way say that removing one of the discs is the solution.

Instead learn to use them.


KM
 

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I would rather make something fit me than have to learn to fit it. Out of all the motorcycles I've ever had, the Vulcan 750 is the only one I ever thought had a front brake problem. It was simply too easy to lock the front wheel with "normal" pressure on the lever. I put 80,000 miles on a '93, and 20,000 on an '02, and never did like it or get used to it. I have 3 other street legal bikes. A near new '09 EX500 (single disc), an '04 Rebel 250 (single disc), and a '94 Yamaha XT225 (single disc) The front brakes on all 3 of these bikes work just fine and feel just fine. They are completely stock. Now, after my modification, the front brake on my Vulcan 750 feels just like brakes on the other 3 bikes. So what's the deal? Do the other 3 bikes have bad brakes? I can lock the front wheel on the Vulcan now with 2 fingers, but it takes quite a squeeze. It is near effortless with all 4 fingers, but is still easy to modulate. You have a choice. You can brake the normal way easily, or, if you really want to lock up the front wheel and crash, you can do that pretty easy too. Before, just thinking about squeezing the brake lever would lock the front wheel. Sorry, but it's just not supposed to be that way. Again, I am not recommending my modification, but it has sure worked well for me over the past 25,000 miles.


BTW, did you know that the "fake" fly by wire controls in today's modern airliners have a specific amount of resistance built into them, just to give them the proper "feel", like "real" controls used to have? Jerry.
 

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ExNewbie..Still Learnin'!
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I think what Jerry touched on is basicly true, and my thinking here whoever knocked your bike over appearently also knocked the air out of your brake hoses and your bike is working like it is supposed too.

Brakes that are working right should lock the wheel with the same effort every time. Your speed of course makes a difference here, as it is easier to lock the wheel at parking lot speeds as opposed to normal road speeds.

To me the duel discs on the Vulcan were the best selling point. It does of course take some time to learn the various limits of braking pressue for each given speed and road condition. My thinking is that the brakes on the bike are not "too much" , but simply too efficiant for some riders. Given the weakass rear brake, I feel that this is really a good thing and would not in any way say that removing one of the discs is the solution.

Instead learn to use them.

KM
I have to agree with you KM. The key is learining your bike and how it reacts under as many different scenarios as possible.

The bike was engineered the way it was for a reason (and then produced that way for 20 years!). If it was a design flaw, they would have likely changed it in the course of that time based upon market feedback.

It's a matter of personal opinion on whether one "likes" the way the bike is designed (hence the multitude of modifications people make to their bikes) but changing a major safety feature may not be the wisest choice.

Seems to me that one should take more time learning the basic riding skills needed to ride safely in all situations, rather than re-engineering to this level. One could also ride the bike on just the aluminum rims because it would "look cool" but probably wouldn't be very wise either.

If you think you know how to ride a bike, ours or any other, check out Mike "Motorman" Palladino's riding exercises and see if you can duplicate them. I'm not connected to him or his biz in any way but sure found the exercises valuable in learning (and still learning) how to really ride a bike safely and with precision.
 

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I have to agree with you KM. The key is learining your bike and how it reacts under as many different scenarios as possible.


Thanks for the support. ;)

I should mention that the front brake on my FJR ( a bike with enough horsepower to scare the crap out of you) is just as "touchy" as the Vulcans....and at only a hundred pounds more, the bike also takes a bit of a learning curve to know where too much is too much....but does have the advantage of a ABS system. So at least you have a back up to avoid locking the front wheel. but once learned, you can haul the bike down to stop in insanely quick times without even triggering the ABS.


That said I had no issues with the front brake on the Vulcan, and as I mentioned found the brake to be one of the better aspects of the bike.

I would guess those that are too lazy to learn ;)....or are used to too many other shoddy brakes on other bikes, or never had any balls to the wall experiance with racetrack ready motorcycles .....could easily fault the Vulcans brakes as being a bit of "overkill" in their opinions. My first guess here is this is from folks that are scared to use the rear brake.....
.....or those that have never really understood that one needs to "connect" with ones bike...it is not just a motorcycle...it is an individual just like you.

Yes, it is not just a simple machine...it is an seperate entity,and at the same time ....an extention of you. Take the time to learn the bike and let it become part of you.


KM
 

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In 1952, I drove my boss's new Packard with power brakes. I nearly went thru the windshield. I soon learned not to stomp on them, like with my old Ford. Now, of course, we all have power brakes and consider them a necessity. We have to learn to adapt. I could tell about power steering too, but you get the picture. I wish the Vulcan had a stronger rear brake, but even us old people "gradually" adapt.
 

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This is NOT an argument. I'm not getting into any more arguments about something that is not worth arguing about. I did it my way, you do it yours, everybody's happy.


As for the way the Vulcan was designed, we all know the Vulcan has numerous design flaws, and that Kawasaki never fixed a single one of them during it's entire 22 year production. They couldn't fix something as simple as that dumb tool box door, and it should have been obvious to even a non engineer that the way they did it couldn't possibly work (and as we all know, it didn't). Owners have been rigging up ways to deal with many of the Vulcan's problems, that's all I did. No difference between that and changing from ACCTs to MCCTs. Hell I even changed the exhaust, which then required rejetting the carbs.


Bikes designed back then came with all kinds of things that newer bikes don't usually have. Most 800 class cruisers today only have one front disc. They also don't usually have shaft drive, cast wheels and tubeless tires, full instrumentation, a centerstand, hydraulic valves, etc. that cruisers back then had.

I might also mention that neither my car nor truck have power steering or brakes, and I like it that way. I like the steering and brake feel of non power assisted steering and brakes, and am plenty strong enough to easily lock the brakes on my car, truck, and all my bikes. No, none of them have anti lock brakes either. Jerry.
 
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