Changing Front Brakes Nightmare

robby · Post by **robby** » Sat Sep 03, 2011 6:41 am

Hi all,

Just wrapped up a 3-hour hassle attempting and failing to change my front breaks. I was wondering if I could get some insight.

First, when I popped off the brake and took out the worn-out brake pads, the space between the clamp was way, way, way too small to fit in new pads. In fact after a minute, it was so narrow that I didn't even have enough room to put the old pads back in. I've heard that hydraulic brakes are self-adjusting, but these did not adjust even once the brake pads were completely removed.

After an hour of finagling, I set the brake down, picked it back up, and voila - it widened! But not completely, and not enough for the new pads. Frustrated and wanting to get my scooter rideable again, I spent the next hour and a half trying to put the old pads back in. I kept getting one and then popping it out while trying to get the other. This probably happened 80 or so times, I really can't believe I didn't give up.

Finally, I got the old pads back in, and connected the brake again. Gave a squeeze and got nothing. Gave five more squeezes, and it adjusted nicely. But... I still need new brakes.

Any thoughts on what I might have done wrong or why I found this so difficult? It seemed like a fairly straightforward operation, there was just zero room to work with inside the caliper.

Thanks in advance for any help.

k1dude · Post by **k1dude** » Sat Sep 03, 2011 7:22 am

I believe you have to depress the pistons fully before installing the new pads. Then after installation they will self adjust with a few pumps of the brake lever. You may have to use a brake caliper compression tool to depress the pistons properly.

jasondavis48108 · Post by **jasondavis48108** » Sat Sep 03, 2011 12:24 pm

k1dude wrote:I believe you have to depress the pistons fully before installing the new pads. Then after installation they will self adjust with a few pumps of the brake lever. You may have to use a brake caliper compression tool to depress the pistons properly.

Yup, when I replaced the front pads on my Buddy 50 I had to get in there and depress the piston. If I remember correctly, what I ended up doing was placing a rag over the piston and working it down with my thumbs. It was hard, the piston does not like to go back into the caliper, you just have to keep at it. You also want to put some lube on the piston, I think I mention this in the how-to that I posted as I can't remember exactly what lube is recommended.

Lotrat · Post by **Lotrat** » Sat Sep 03, 2011 1:14 pm

You need to push the piston in. Here's a good video showing this on a car, but it's the same concept for a scooter.

<iframe width="420" height="345" src="http://www.youtube.com/embed/xOkbcAdw0Es" frameborder="0" allowfullscreen></iframe>

robby · Post by **robby** » Sat Sep 03, 2011 5:00 pm

Thanks guys, I applied a little force to the piston but it didn't go in so I just gave up. I guess I should have thought to try really cranking on it. Will try the c-clamp method.

Also thanks jasondavis for your tutorial here: topic14596.html

Unfortunately the Roughhouse 50's brakes are a little bit different (I didn't have to deal with a cotter pin - the pads are held in by a metal piece wedged between the pad and the chamber. A nice step to be able to skip but it is damn near impossible to get the pads wedged in properly. If the NCY brake were a little less money I'd probably just replace the whole assembly to make this easier in the future.

Will give this all another try later in the week. Thanks again everyone.

Syd · Post by **Syd** » Sat Sep 03, 2011 5:14 pm

Did you loosen the fluid reservoir cap so that the fluid can get back up the line?

jijifer · Post by **jijifer** » Sat Sep 03, 2011 5:20 pm

jasondavis48108 wrote:
k1dude wrote:I believe you have to depress the pistons fully before installing the new pads. Then after installation they will self adjust with a few pumps of the brake lever. You may have to use a brake caliper compression tool to depress the pistons properly.
Yup, when I replaced the front pads on my Buddy 50 I had to get in there and depress the piston. If I remember correctly, what I ended up doing was placing a rag over the piston and working it down with my thumbs. It was hard, the piston does not like to go back into the caliper, you just have to keep at it. You also want to put some lube on the piston, I think I mention this in the how-to that I posted as I can't remember exactly what lube is recommended.

can this go into double entendre?

jasondavis48108 · Post by **jasondavis48108** » Sat Sep 03, 2011 6:58 pm

jijifer wrote:
jasondavis48108 wrote:
k1dude wrote:I believe you have to depress the pistons fully before installing the new pads. Then after installation they will self adjust with a few pumps of the brake lever. You may have to use a brake caliper compression tool to depress the pistons properly.
Yup, when I replaced the front pads on my Buddy 50 I had to get in there and depress the piston. If I remember correctly, what I ended up doing was placing a rag over the piston and working it down with my thumbs. It was hard, the piston does not like to go back into the caliper, you just have to keep at it. You also want to put some lube on the piston, I think I mention this in the how-to that I posted as I can't remember exactly what lube is recommended.
can this go into double entendre?

wow! didn't realize how bad that would sound

robby · Post by **robby** » Sat Sep 03, 2011 7:57 pm

Syd wrote:Did you loosen the fluid reservoir cap so that the fluid can get back up the line?

Do you mean the cap on the caliper or the cap on the master reservoir by the handlebars? I didn't loosen either - I thought that was only necessary for bleeding the brakes. No?

Beamster · Post by **Beamster** » Sun Sep 04, 2011 4:36 am

For cars and bikes:
You probably want to take the cap off and the rubber seal to reform the seal.
If you have added fluid during the life of the pads you are going to have to remove some fluid from the master cylinder before compressing the caliper piston, otherwise you are going to get an overflow and lose some paint.

The best way to effortlessly compress the piston is with a steel C clamp.

rsrider · Post by **rsrider** » Sun Sep 04, 2011 4:50 am

Take off the caliper,remove brake reservoir cap, take some fluid out (I usually remove half the fluid with a paper towel, making sure you don't get the fluid on ANYTHING, and make sure you have brake fluid to fill up the reservoir when done), pull the old pads, clean the pistons and calipers with brake cleaning fluid, depress the brake pistons (you can use a wrench across the pistons, and push down), insert the new pads, place calipers back on the bike, work the lever until you get some feel back, fill up the brake fluid reservoir and replace the cap, back to the lever, and then go out and seat the brakes. It's just a process and once you do it a couple times, you'll get the steps down. Next, draining the brake fluid.......................

Syd · Post by **Syd** » Sun Sep 04, 2011 6:10 am

robby wrote:
Syd wrote:Did you loosen the fluid reservoir cap so that the fluid can get back up the line?
Do you mean the cap on the caliper or the cap on the master reservoir by the handlebars? I didn't loosen either - I thought that was only necessary for bleeding the brakes. No?

Master reservoir.

jasondavis48108 · Post by **jasondavis48108** » Sun Sep 04, 2011 1:19 pm

robby wrote:
Syd wrote:Did you loosen the fluid reservoir cap so that the fluid can get back up the line?
Do you mean the cap on the caliper or the cap on the master reservoir by the handlebars? I didn't loosen either - I thought that was only necessary for bleeding the brakes. No?

When I changed my brake pads I did not remove any of the brake fluid. It may make the pads easier to depress though.

viney266 · Post by **viney266** » Sun Sep 04, 2011 3:33 pm

and just a tip from a mechanic. put a rag or even better a piece of leather between the clamp and the caliper face. On bikes and scoots you need to keep them pretty and not scratch them up if the c clamp slips.

Syd · Post by **Syd** » Sun Sep 04, 2011 7:29 pm

jasondavis48108 wrote:
robby wrote:
Syd wrote:Did you loosen the fluid reservoir cap so that the fluid can get back up the line?
Do you mean the cap on the caliper or the cap on the master reservoir by the handlebars? I didn't loosen either - I thought that was only necessary for bleeding the brakes. No?
When I changed my brake pads I did not remove any of the brake fluid. It may make the pads easier to depress though.

Removing fluid should only be necessary if you have added fluid in the reservoir as the brakes have worn down.

robby · Post by **robby** » Mon Sep 12, 2011 7:55 pm

Okay guys, think we're set! I replaced the front brakes with your advice using a C-clamp to get the piston back in and things went much more smoothly. Put it back together, squeezed the break a few times, and it caught perfectly.

Only hitch: the new front brake is definitely rubbing against the rotor even with the brake released. I blew out any possible dust that could be in there. Is this part of normal break-in or did I do something wrong?

Syd · Post by **Syd** » Mon Sep 12, 2011 8:42 pm

Is it just brushing the rotor? That's not uncommon, and is to be expected. If that's the case it will seat in after some miles too.

If it is rubbing to the point that it keeps the front wheel from spinning, that's another issue entirely.

robby · Post by **robby** » Mon Sep 12, 2011 8:51 pm

edit: Disregard pre-edit.

It definitely doesn't stop the wheel. I guess you could say it brushes, but maybe a little more than just a brush?. If I give the wheel a good kick, it will role around about 3 times before stopping.

babblefish · Post by **babblefish** » Tue Sep 13, 2011 10:24 am

Perfectly normal with all disk brakes. Don't worry about it.

robby · Post by **robby** » Tue Sep 13, 2011 3:59 pm

Excellent, thank you. I don't remember it doing that before but I might have just not been paying attention to it.

mikebuddy · Post by **mikebuddy** » Tue Sep 13, 2011 5:47 pm

what size hex tool do you use to take apart the front brake pads on a buddy 150

Modern Buddy

Changing Front Brakes Nightmare

Changing Front Brakes Nightmare

buddy front brakes question