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Discussion Starter #1
ok, I had new brakes put on my bike last summer, 4k miles ago and I started hearing a scraping sound. Took off the brake pads and the right side brake pad (small pad) is seriously worn. Was wondering if anyone had some ideas what may have caused this. I've cleaned the calipars and had been told by another biker that I should lightly sand around the outside of the piston and see if that helps (I guess he was thinking the piston is sticking and the sanding would make sure nothing was catching). I am not a mechanic and bought this bike so I could learn how do work on things. So, I've got everything taken apart and ready to replace brake pads myself this time and get back to riding (after giving the brakes a could check in the drive way!!!).

Just had to see this happen again so any ideas are welcome! Thanks
 

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If you are having excessive brake wear on the front, there is only two possibilities. Either the caliper is not releasing properly, or you are "riding the brake" Assuming you are using the brake properly, there are a couple of things that can cause the brakes to drag. The pistons may be stuck in the caliper by corrosion of crud buildup, or there is a blockage in the hydraulic system that is not allowing the pressure to completely release. It can be in the caliper or master cylinder, but is almost always in the master cylinder.

The Vulcan certainly has plenty of front brakes, and the pads should last at least 12K to 15K, even with a lot of in town riding.

Oh, one more thing. What kind of pads are you using? If you are using Chinese pads from eBay, that is the likely cause. I use EBC organic pads.
 

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Discussion Starter #3
Thanks for the response. I am putting new pads on (the EBC organic-found the recommendation on here for those) as soon as I get them. I've cleaned the piston up as much as possible. For some reason (maybe crud) the piston was hanging up. My master cylinder looks good. I'll just keep an eye on the pad to make sure the piston is releasing and see what happens. Just not sure what else to do.
 

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Put the bike on the centerstand, and put something under the engine to raise the front wheel off the ground. Spin the wheel. If you feel anything but very light drag, something is wrong. Check it after riding a few miles. If the discs are hot, then the brakes are dragging. If so, you will need to do something about it. If it seems to be the calipers, then they need to be disassembled, thoroughly cleaned, and put back together with all new seals, then bled properly. If you find any corrosion on the pistons or in the bores, you can polish it out with fine sandpaper. If you know the calipers are good, then the problem has to be in the fluid return hole in the master cylinder. You may be able to unplug that without taking the master cylinder apart. It should be a small pinhole in the bottom of the reservoir.
 

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Actually, bad rotors will cause premature brake wear as well. If yours have lines gouged all the way around, time for a cutting (if its even possible) or new rotors. New pads will wear into these grooves unevenly. You can get away with it for awhile (with much pad wear), but better to have smooth rotors. Increases surface area for pad to rotor contact.
 

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Captive New Yorker....
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ok, I had new brakes put on my bike last summer, 4k miles ago and I started hearing a scraping sound. Took off the brake pads and the right side brake pad (small pad) is seriously worn. Was wondering if anyone had some ideas what may have caused this. I've cleaned the calipars and had been told by another biker that I should lightly sand around the outside of the piston and see if that helps (I guess he was thinking the piston is sticking and the sanding would make sure nothing was catching). I am not a mechanic and bought this bike so I could learn how do work on things. So, I've got everything taken apart and ready to replace brake pads myself this time and get back to riding (after giving the brakes a could check in the drive way!!!).

Just had to see this happen again so any ideas are welcome! Thanks
Did you find it easy to get the pads out? Changing the front pads is on my list of projects that I need to take care off......
 

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Just changed my pads and they weren't too hard to remove. Took me about 15-20 minutes to do it. Need a c-clamp to make things easier. Got some Kelvar pads, Sumo brand, off ebay, $30.00 total shipped bot both rotors.

Here's the link for the auction... Kevlar Pads or you can buy them for $37.75 ShippedBuy pads - no auction

They bedded in nicely after running the bike up to 30+ mph, braking easy, running it up... braking hard... up - easy, repeat for the next 50 times.
Feel on the pads are good, no squalling and no surprises. Stopping power will only get better when they get fully bedded in.
 

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Captive New Yorker....
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Great, thanks for the info.....
 

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And while you are working on the brakes, it would be a good thing to flush and change the fluid. Books calls for this to be done every two years or 15,000 miles.
 

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Discussion Starter #10
pads were easy to change! If you haven't changed pads before you tube has some motorcycle brake changing videos that will give you a good idea what you are doing plus check your maintenance manual. My piston wasn't retracting and wore one of the pads down. So I cleaned the caliper and piston up and lightly lubed the piston hoping it will retract after braking this time. If not looks like I will need to replace the caliper.
 

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Linkmeister Supreme
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Actually, bad rotors will cause premature brake wear as well. If yours have lines gouged all the way around, time for a cutting (if its even possible) or new rotors. New pads will wear into these grooves unevenly. You can get away with it for awhile (with much pad wear), but better to have smooth rotors. Increases surface area for pad to rotor contact.
The vn750 rotors are not thick enough to take machining back to a flat surface without dropping below specs.
 

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That figures...because mine looks like an oldstyle coal based record made on a Monday, lol. Guess I'll just keep replacing pads for now. Then again...them "specs" are set by engineers, who include a lil extra (like pharmaceutical companies add expiration dates that are premature) to cover their butts. My gouges aint too deep, and I use engine braking mostly, I bet I can get away with a light cutting.... *innocent look*....
 
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