Clinician
Currently Offline
Posts: 3
Likes: 0
Joined: May 9, 2016 18:12:47 GMT -6
|
Post by ph1l on May 9, 2016 18:30:11 GMT -6
Hello Scooter Doc Community, my name is Phil and I just signed up because I experienced really weird issues with my front brake today. Quick Fact: I bought this 150cc scooter last week. The lady I was buying it from told me that she had the scooter at a mechanic and he checked/fixed everything there before selling it. Everything is documented so I guess that's correct. However, she also said that her mechanic told her that the brake cylinder needs to be replaced soon. The main brake cylinder for the front break (located on the right handle bar). I did a test drive, everything felt smooth. The front end however was a bit shaky, I thought of the brake cylinder and didn't really bother much more. So today I took the scooter on my way to work and after I filled my gas tank, the front brake felt like it would lock a little bit. After a little while, it went from bad to worst and it literally locked my front wheel. I could feel it when I was taking off from standing, I had to accelerate a lot in oder to get it going. Also, the brake on the handle bar was not usable anymore. It was stiff as a piece of solid metal. That moment I felt I can't go any further and so did my scooter. I was rolling when suddenly the front wheel just locked completely and I was sliding over my front wheel and put that baby down. After getting my scooter back to my apartment, I ordered a brake cylinder but I still don't exactly know if that was the issue. I checked on the break fluid (opened the box where the fluid is in, fluid looks clean, good and also on a good level), opened the screw at the bottom of the break to get any sort of air out, closed it again and also checked the brake disk + brake lines. all of that looks good to me. The only concern I found was that the brake disk looks pretty close to the part where the brake pads are in. I don't know if that should be this close tho. I can make a picture for you guys if you think it's worth checking. When I had the scooter at home, I used the brake a bunch of times and then tried to move the wheel. It was really hard to keep the wheel going so I realized I still have the same issue. After opening the brake lines and putting everything together again it at least looks like the wheel doesn't lock up anymore if I use the brake a bunch of times and then spin the wheel. I'm not sure if it's the cylinder or if something's not right with that little space I have between brake disk to that part where the brake pads are in. I hope anybody of you can help me out here Thanks a lot for your time and can't wait to hear your opinions.
|
|
|
Post by Alleyoop on May 9, 2016 19:36:56 GMT -6
Could be the plunger not returning and the brakes always haveing pressure. Here is how the Hydraulic mechanism works on your scoot: Check on the side as you press the brakes and you will see the brake handle push the plunger and when you release it the plunger should come back out. If it is getting stuck that will keep pressure on the brake piston and on the brake disc. Alleyoop scooterdoc.proboards.com/thread/8198/hydraulic-disc-brakes-working
|
|
|
Post by Alleyoop on May 9, 2016 20:28:57 GMT -6
|
|
|
Post by cyborg on May 9, 2016 22:25:59 GMT -6
Does it only happen when it's hot?,,,turn freely when cold but locks up when hot?,,, there's a vent in the cylinder that lets expanding fluid back into the reservoir,,,if that return vent is blocked the brakes will come on automatically when the fluid gets warm
|
|
Clinician
Currently Offline
Posts: 3
Likes: 0
Joined: May 9, 2016 18:12:47 GMT -6
|
Post by ph1l on May 10, 2016 11:08:04 GMT -6
Thanks for your responses. Yesterday I opened the brake cylinder again to see if I can spot the plunger but I couldn't. There are just 2 small holes and I wasn't able to see anything moving through them. However, I took it for a quick ride and everything seemed normal.
The vent thing could be a good hint. The scooter was def. hot by the time I crashed. I already ordered a new brake cylinder and it should arrive Friday. With that new brake cylinder I should be able to fix either of the two possibilities you suggested.
I'll keep you updated! Thanks!
|
|
|
Post by Alleyoop on May 10, 2016 16:06:01 GMT -6
NO!! look on the side where the BRAKE HANDLE PUSHS IT IN WHEN SQUEEZING THE BRAKES.
|
|
|
Post by crwford on May 10, 2016 19:42:21 GMT -6
Just thinking did anyone try bleeding the brakes?
|
|
|
Post by Alleyoop on May 10, 2016 20:03:37 GMT -6
They are stuck in the closed position bleeding is not going to help that situation. It has to be the plunger is not releasing the pressure after you left go of the brakes the brakes stay on. So I would suspect the plunger not returning back, broken or very weak spring or the rubber seals are damaged and causing the plunger to bind. Alleyoop
|
|
|
Post by cyborg on May 10, 2016 20:35:39 GMT -6
I think your right on yet again Alley,,,the master is shot,,,I personally wouldn't run it,,,,the bike needs to be taken out of service till repairs are done,,,
|
|
Clinician
Currently Offline
Posts: 3
Likes: 0
Joined: May 9, 2016 18:12:47 GMT -6
|
Post by ph1l on May 16, 2016 11:27:39 GMT -6
I got my new brake cylinder installed and also took the scooter for a run this morning. Everything seems pretty smooth. I just need to re-adjust the brake a little bit more cause right now it barely brakes but that's not a big deal.
Thanks for all your comments and help guys, really appreciate it!
|
|
|
Post by cyborg on May 16, 2016 12:48:37 GMT -6
Good glad you got it sorted,,,,, bleed the system and adjust it and you're good to go,,,, good job
|
|