Help me with my brakes

wehey

Pedelecer
Feb 13, 2014
117
7
53
I have Shimano Deore V brakes on my bike.
The front is really good and snappy and works well.
The rear is horrible and spongy and squeezing fully won't lock up the wheel.

I have checked it over and there's little friction between the out and inner cables. Maybe it's the inner cable stretching?? I don't really know?

Anyone have any advice? Maybe an upgrade?
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,592
1,747
70
West Wales
V brakes can be like that. It's a long cable to the rear, might be worth splashing out on a known good cable, something like JAG.
 

Trevormonty

Esteemed Pedelecer
Jul 18, 2016
1,135
564
17
NZ
Alternatively upgrade to hydraulic Magura rim brakes eg HS11 or disc brakes it frame has mount points.
 

JPGiant

Esteemed Pedelecer
Sep 3, 2017
364
167
West Yorkshire
For the costs involved I'd change the inner cable and outer sleeving.
The outer could be rusty inside or even have a groove in it from the cable rubbing .
 
  • Agree
Reactions: Wheel-E

Wheel-E

Pedelecer
Jul 14, 2017
97
27
Brighton
I have Shimano Deore V brakes on my bike.
The front is really good and snappy and works well.
The rear is horrible and spongy and squeezing fully won't lock up the wheel.

I have checked it over and there's little friction between the out and inner cables. Maybe it's the inner cable stretching?? I don't really know?

Anyone have any advice? Maybe an upgrade?
When you say it sounds spongey, to me it sounds as if you need the brake blocks closer to the rim so you can get more pressure onto the wheel. It's as if the brake blocks are only touching the wheel near the end of their travel. This can happen as the brake blocks wear down or as the cables stretch.

How are the brake blocks looking? Is it time to replace them? Have you tried turning the adjuster on the brake lever to tighten things up? Does that make any difference? If that's not enough adjustment you may need to tighten the cable where it meets the brakes at the rear so you can get more more pulling power.

No harm in adding fresh cabling too as although it may not be entirely to blame, it will reduce friction in the system.
 

wehey

Pedelecer
Feb 13, 2014
117
7
53
When you say it sounds spongey, to me it sounds as if you need the brake blocks closer to the rim so you can get more pressure onto the wheel. It's as if the brake blocks are only touching the wheel near the end of their travel. This can happen as the brake blocks wear down or as the cables stretch.

How are the brake blocks looking? Is it time to replace them? Have you tried turning the adjuster on the brake lever to tighten things up? Does that make any difference? If that's not enough adjustment you may need to tighten the cable where it meets the brakes at the rear so you can get more more pulling power.

No harm in adding fresh cabling too as although it may not be entirely to blame, it will reduce friction in the system.
I have tried adjusting them many times with no difference.
I will try the cables next
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,592
1,747
70
West Wales
Trouble with V brakes is you can never get them to release equally and consistantly. Meaning you can't get the blocks as close as they really need to be. I'm forever adjusting the rear one on the wife's Big Bear and it started rubbing again yesterday.
I have a Magura HS11 on the front of another bike and it's been no trouble since it was set up. Might seem like a bit of overkill but then this is safety we're talking about.
 

Trevormonty

Esteemed Pedelecer
Jul 18, 2016
1,135
564
17
NZ
Trouble with V brakes is you can never get them to release equally and consistantly. Meaning you can't get the blocks as close as they really need to be. I'm forever adjusting the rear one on the wife's Big Bear and it started rubbing again yesterday.
I have a Magura HS11 on the front of another bike and it's been no trouble since it was set up. Might seem like a bit of overkill but then this is safety we're talking about.
I've just setup one set of HS11s, not as simple as Magura video makes it out. But that could've been for HS33. If their reputation is anything to go by that should be it for a few years with occasional new pads (2minute job) and adjust screw in hand piece occasionally.

I'd say they have similar performance to entry level shimanos 160mm disc brakes, definite enough for city commuter with 25kmh cutoff.
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
7,845
5,786
The European Union
I've just setup one set of HS11s, not as simple as Magura video makes it out. But that could've been for HS33. If their reputation is anything to go by that should be it for a few years with occasional new pads (2minute job) and adjust screw in hand piece occasionally.

I'd say they have similar performance to entry level shimanos 160mm disc brakes, definite enough for city commuter with 25kmh cutoff.
+5000 km on original pads. Can do stoppies. Never tried entry level hydraulic disks so can't compare. I feel safe braking from over 45 km/h and with trailer full of shopping.