E-bike hydraulic break problem

functionalfool

New member
Local time
6:31 AM
Joined
Feb 6, 2024
Messages
11
Location
MI
I got a new ebike and although the brakes were a little loose, I was forced to brake so hard I almost locked up both wheels.
Now they are REALLY loose! There is a screw to tighten both brakes and both are at 100%.

Front brake literally does nothing and rear brake is at 30%.

My bike is Keteles with 1000w motors on both wheels and it's capable of 35mph so it needs to be able to stop fast!
 
Sounds like the brake cables have slipped, or you don't have any brake pads left. Since your bike is new, its probably the cable being loose or stretched. I'd check those 2 things first. When you go to adjust, make sure you move the cable tensioners back so they can be adjusted again.
 
That's not normal for "really hard breaking" to destroy your breaking power. So I would be concerned, if not scared. A long decent with lots of load definitely can overheat the discs and build a melted film on the pads. Possibly just changing the pads will do it. If it's a hydraulic fluid problem it sounds like it's worth taking to a pro because it's not normal for them to depower like that unless you have a serious fluid leak or something.

For what it's worth I'm an experienced at home DIY mechanic with lots of custom bike builds under my belt and hydrolic disc breaks is the one thing I prefer to have done by the pros at my local bike shop because I know they will do a better job than I will.
 
That's not normal for "really hard breaking" to destroy your breaking power. So I would be concerned, if not scared. A long decent with lots of load definitely can overheat the discs and build a melted film on the pads. Possibly just changing the pads will do it. If it's a hydraulic fluid problem it sounds like it's worth taking to a pro because it's not normal for them to depower like that unless you have a serious fluid leak or something.

For what it's worth I'm an experienced at home DIY mechanic with lots of custom bike builds under my belt and hydrolic disc breaks is the one thing I prefer to have done by the pros at my local bike shop because I know they will do a better job than I will.
If they get really hot,. just stop & let 'em cool off. Failure on a long steep descent is not an option. Same with rim brakes;
the heat can pop a tube.
 
It's not so much a matter of miles but the right bad conditions (big load long decent) to destroy my pads. My lightweight recumbent ebike lasts a long while but with my heavy cargo bike (bike weighs 100+ pounds, cargo often exceeds 200 pounds), i have on multiple occaisions overheated the pads to destroy them.

For this reason I am going to upgrade it to a "grin" phaserunner dd rear hub system with sereious regenerative breaking, like I already have on my other bike. Not so much interested in the 5 - 10% energy efficiency gain so much as the improved breaking life. I also need to upgrade from 160 mm rotors to something bigger (180 or 200), but haven't done this yet.

Break life on an electric bike is a serious issue. We are using essentially bicycle parts but with heavier loads, longer miles, and higher speeds than what they are designed for.
 
I got a new ebike and although the brakes were a little loose, I was forced to brake so hard I almost locked up both wheels.
Now they are REALLY loose! There is a screw to tighten both brakes and both are at 100%.

Front brake literally does nothing and rear brake is at 30%.

My bike is Keteles with 1000w motors on both wheels and it's capable of 35mph so it needs to be able to stop fast!
Mechanical or hydraulic, discs. pads can be fairly simple. I remove mounting bolts & cup it iny one hand on my lap.
It's not unlike shoeing a horse
 
I'm sorry about posting and disappearing! Life kinda happened. Posting pics of my brakes in immediately after this post
 
IMG20240318014253.jpg
 
More pics
 

Attachments

  • IMG20240318014807.jpg
    IMG20240318014807.jpg
    155.4 KB · Views: 27
  • IMG20240318014753.jpg
    IMG20240318014753.jpg
    167.8 KB · Views: 24
  • IMG20240318014738.jpg
    IMG20240318014738.jpg
    153.7 KB · Views: 24
More pics
Could also be air in the line. On Utube there are a number of tutorials on hydraulic discs. Watch 'em all, some are better than others.
some mainly just want to sell product. I prefer mechanical, they need more frequent adjustment, but I'm less likely to do a face
plant with a panic stop. Actually I put a rim brake on the rear. Spokes on the disc side can be a real struggle to replace with a disc.
Hydraulics never need adjustment....until they do. I haven't had a spoke issue since i completely rebuilt the motor wheel with small
brass washers at the hub with 13g spokes instead of 14g. I still check for loose spokes before every ride, better than the alternative.
So far I've kept the new rim I used true to .5 mm. for a cpl thousand mi. I'm finicky that way. Good wheel building vids on Utube too,
but you need the watch them all to get a real mastery of the skill. I built mine right on the bike with no special apparatus.
 
Back
Top