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Discussion Starter #1
I'm thinking of changing my front brake calipers, for a twin piston set off a 750 gpxr, looks like more contact area on the discs from the larger pads. The twin piston set up with it's large and small pistons, may work better than the factory set. Seems the doener bike was a bit of a racer, hence the "R" for race.
How's the opinions on this idea?
 

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I'm thinking of changing my front brake calipers, for a twin piston set off a 750 gpxr, looks like more contact area on the discs from the larger pads. The twin piston set up with it's large and small pistons, may work better than the factory set. Seems the doener bike was a bit of a racer, hence the "R" for race.
How's the opinions on this idea?
May be better brakes but the ones on the front are more than enough for the tires these bikes run. If you do decide to change make sure to do a bunch of measuring,bolt placement ,offset from the center, disc thickness,and if your master cylinder is capable of pushing enough fluid to operate the twin pistons.

It would be iffy at best making the swap.but with enough time patience and money most obstacles can be over came.if it were me I would look at swapping the whole fork or at least the legs if they are the same diameter and length as yours.Might be easier and cheaper .
Plus you will be able to run the front wheel off the donor bike and possibly a better tire.

If your front brakes are not doing the job ,I would rebuild the stock calipers and master cylinder and see if they aren't as good as you need then.Maybe you could save money enough to tackle another project you want to do on your bike, Never ask for an opinion on here,they come unsolicited most of the time but since you did, there's mine. :smiley_th
 

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Increasing brake capacity on the front of a VN 750 seems to be a bit counter to what several members have done in the past. Many have switched from dual to single discs on the front because they felt the stock brakes had too much grab when in proper working order. As mentioned in the previous post if you believe you need to increase the stopping ability of your particular ride you may have a potential problem with your bike and should check that out first before you put the time and effort to change it all out. This is all just opinion here right now as you asked for. Good luck with you decision and follow up.
 

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Discussion Starter #4
progressive.

I think these other brakes are a progressive design, suggesting that the smaller piston is more sensitive to pressure and applies quicker but less forcefully than it's larger partner, that presumably, takes a larger part of the load under extreme stop maneuvers. So from your knowledge concerning grabbing, and an over direct stopping application. Perhaps these units, being just a few years later in design, may well have been made to counter concerns of snatching brakes. The front wheel of the parts bike is a 17'', and I have found the factory Vulcan 19'' to be more my style, and comfort level. So now i think it's time for a closer look at the offsets and mounting arrangements, seems the replacements have a multi fit bracketing system, that may well come in handy.
I'll keep you posted on the outcome.
 

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All I ever use is the front brake and my bike has more than enough with the factory setup. Couldn't imagine more braking power or being quicker.
 

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I think these other brakes are a progressive design, suggesting that the smaller piston is more sensitive to pressure and applies quicker but less forcefully than it's larger partner, that presumably, takes a larger part of the load under extreme stop maneuvers. So from your knowledge concerning grabbing, and an over direct stopping application. Perhaps these units, being just a few years later in design, may well have been made to counter concerns of snatching brakes. The front wheel of the parts bike is a 17'', and I have found the factory Vulcan 19'' to be more my style, and comfort level. So now i think it's time for a closer look at the offsets and mounting arrangements, seems the replacements have a multi fit bracketing system, that may well come in handy.
I'll keep you posted on the outcome.
put an inverted front on mine with 4 pot calipers and 300mm disc from old zxr among other changes,doesn't look like i'll finish it any time soon since loosing job,otherwise i would let u know on stopping power.Try braided lines before changing originals.
 

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^ what he said about braided lines.

Doing this I doubt you'll find any difference between the stock set up and what you propose. Brakes work by surface area, the stock units offer this above many others.
It's really about skill and training here. Those they think the stock brakes are too "grabby" just haven't spent the time training themselves how to use them, or how to brake properly in the first place.
 

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FREEBIRDS MC CENTRAL NY
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I've seen this done on other bikes.if you need to custom make brackets for the calipers you can use the stock mounts as a base and then go from there.there's a guy called Fabricator Kevin outta Detroit that makes mounts for Harleys that bolt Japanese calipers to the stock Harley mounts.
 

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Brake upgrade

I think these other brakes are a progressive design, suggesting that the smaller piston is more sensitive to pressure and applies quicker but less forcefully than it's larger partner, that presumably, takes a larger part of the load under extreme stop maneuvers. So from your knowledge concerning grabbing, and an over direct stopping application. Perhaps these units, being just a few years later in design, may well have been made to counter concerns of snatching brakes. The front wheel of the parts bike is a 17'', and I have found the factory Vulcan 19'' to be more my style, and comfort level. So now i think it's time for a closer look at the offsets and mounting arrangements, seems the replacements have a multi fit bracketing system, that may well come in handy.
I'll keep you posted on the outcome.
Maybe I am missing your point but I am curious as to why you want to upgrade the brakes. I will admit that what you describe is probably better that stock. What would be nice is ABS.

My 03 has the factory stock progressive brakes. Front and rear. If I need a little brake, I just don’t squeeze as hard. The fact is, both front and/or back will lock up the tires without any problem, so in regular riding don’t think you will notice much difference in braking. Here in CrAzyland you had better plan ahead for the unexpected, then expect to be surprised. I would look for better rubber on the ground for better braking. I went with a Avon Venom this time over the Kenda Kruz. More $ but much better traction. Both on the curves, where the pegs hit either way, and starting and stopping.

My stock pads have 19,000+ miles on them and plenty left. Kind of curious how many miles these will last?
 

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I am 100% against ABS, for several reasons. One, they are controlled by a computer, and I don't believe a computer has any business on a motorcycle. Two, they take away my control of the bike. I want the bike to do what I want, not what a computer wants. Three, they are far from foolproof. I have seen many videos of bikes with ABS going down on slippery surfaces due to a loss of traction. ABS brakes may not completely lock, but they come close enough to cause the tires to lose traction on a slippery surface. Forth, many people believe they are foolproof, that you just apply the brakes as hard as possible and let the computer take care of things. MANY riders have crashed this way. Fifth, They are causing a lot of new riders to not learn proper braking skills, and a lot of experienced riders to forget the braking skills they once had.

As far as the Vulcan 750s brakes, it is definitely overbraked in front. I rode over 100,000 miles on Vulcan 750s, and never did get used to the grabby nature of the front brakes. It was like they were either on of off, nothing in between. I have never had this problem with any other bike, including ones with dual front discs. I've owned two Vulcan 750s, and they were both like that. IMO, it just took to much attention to avoid locking them up, and that they were dangerous in a panic braking situation. I'm one who removed one of my front brakes, now the brakes work just like every other bike I've ever ridden (about 45 of them) I did extensive testing in an unpopulated area before riding in traffic with my modified brakes, and found no problems. They were so much easier to modulate, and it was still easy enough to lock the front wheel (yes, you can do a stoppie on a Vulcan 750) I now have over 50,000 miles on this mod, and consider it proven. But I still won't recommend it. Do it at your own risk.

The Vulcan 750 has many known issues. I believe the front brakes are one of them. I think Kawasaki got a bit over zealous seeing just how much stuff they could cram on the Vulcan. Back when it was designed, lots of features were the big thing.
 

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On my '03 I couldn't imagine needing more front brake than the factory brakes. Plenty of stopping power. I'd suggest picking a different project if you really want to modify something but leave the front brakes alone.
 

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I believe there is more to it than just having to much front brake. I think they got the leverage ratio between the master cylinder and calipers wrong. I've never rode any other bikes, other than 2 Vulcan 750s, that would lock the front brakes with just a tiny squeeze on the lever.
 

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I believe there is more to it than just having to much front brake. I think they got the leverage ratio between the master cylinder and calipers wrong. I've never rode any other bikes, other than 2 Vulcan 750s, that would lock the front brakes with just a tiny squeeze on the lever.
Guess you must have very strong hands....of you were blessed with two Vulcans with grabby brakes. A tiny squeeze?

I found nothing wrong with the bikes front brakes. Yes ... you can under normal conditions ....stop the bike with just two fingers. But I've been on bikes that could do this with one finger.

Problem to me seemed more due to the small front tire, or not being REAL careful on wet roads. Many have reported here going down due to locking the front brake....ONLY in stress pumped panic situations or on slippery/wet roads.

So my thoughts here that something might have been wrong with your brakes. A "grabby" brake can be due to several things....
 

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Discussion Starter #14
Thanks for the feed back guys, I usually find the brakes on most of my bikes suffer from glazing and general high wear. I attribute this to a lot of city/suburban riding, and of course my 110 kg basic weight. I have re appraised the size of the brake pads between the two models of brake pads and found the surface area on the VN brakes to be slightly larger than the GPX. Another factor to consider is the braking system is the GPX has a 16 inch front wheel, this would mean a reduced braking action if applied to the Vulcan 19 inch wheel. given the added work and dubious gain from the alternate brake system, I have concluded that the original brake cylinders,can stay on with a deglaze of the discs and some new pads. Perhaps that 16 inch wheel in the other is there to magnify the brake ability, and to help counter the weight of the 21 ltre fuel tank on the GPX. Any how decision made the VN brakes stay, though a set of braided pipes may be added if found reasonably priced at the local recyclers. Thanks again for the input.
 

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I believe there is more to it than just having to much front brake. I think they got the leverage ratio between the master cylinder and calipers wrong. I've never rode any other bikes, other than 2 Vulcan 750s, that would lock the front brakes with just a tiny squeeze on the lever.
There are worse bikes. Triumph Speedmaster for one.

One could always install an adjustable proportioning valve. Nearly all big/little tire'd race cars use one. They are cheap if they cure the problem and they would.
 
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