E-bike hydraulic break problem

[functionalfool]

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!

 

[major masingil]

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.

 

[DieselTech]

I would invest in a mountain bike hydrualic brake bleed kit.

 

[major masingil]

My bad. You have Hydraulic, yes to what Dieseltech says

 

[HumanPerson]

pics of both brake systems on the bike are helpful

 

[pagheca]

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

I'd be scared s**tless if I were you! Just the idea of losing one of the two brakes is unthinkable for me: even to get out of my property I have to go downhill about 200 meters, with gradients of more than 20% and a stone wall at the end...

 

[CrossRoads]

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.

 

[Rawly Old]

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.

 

[pagheca]

But how many kilometers (or miles) do your brakes last on average, folks?

 

[CrossRoads]

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.

 

[pagheca]

I actually asked just to understand how local conditions (orography, terrain, etc.) affect the brake consumption of an ebike.

 

[HumanPerson]

We love buttersquash some say

 

[Rawly Old]

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

 

[Rawly Old]

But how many kilometers (or miles) do your brakes last on average, folks?

'bout 3000 mi., but I seldom exceed 14 mph. Lately bin pedaling in mode 1. Display showing little of no juice in use.
Gettin' in shap pedaling 70 pds. of bike, pretty bad ss for 75.

 

[functionalfool]

I'm sorry about posting and disappearing! Life kinda happened. Posting pics of my brakes in immediately after this post

 

[functionalfool]

 

[functionalfool]

I think there is a leak in both brake lines and it's unsafe to ride

 

[functionalfool]

More pics

 

[Rawly Old]

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.