Disc Brakes

denwyn

Esteemed Pedelecer
Aug 17, 2013
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We bought a couple of Wisper 705t bikes about a year ago, both very happy with our purchase. Didn’t get a lot of use out of them before we stored them over winter. Not really used them a great deal this year as we moved house and work is on going with builders etc. I’ve done about 280 miles and she’s done about 200. I have noticed the rear brake is much stronger than the front, don’t remember it being like this when we bought them, it works but the rear stops the bike quicker. As there both Hydraulic discs there is no adjustment as far as I can see, I can’t see any fluid leakage either. What should I look for if three is a problem. Taking it back to shop is not an option, as it won’t fit in the car, and no longer easy for us to get there, Any advice appreciated
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Clean the disc with isopropanol and gives the pads a wash in case they have picked up contamination.
Remove pads put a drop of fairy on them rub them together and wash off also a light rub with abrasive paper may help.
 
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Wisper Bikes

Trade Member
Apr 11, 2007
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Hi Denwyn, please take Neal's advice to start with. If this doesn't work please feel free to call our support line 01732 762 393.

All the best, David
 

Woosh

Trade Member
May 19, 2012
19,529
16,466
Southend on Sea
wooshbikes.co.uk
We bought a couple of Wisper 705t bikes about a year ago, both very happy with our purchase. Didn’t get a lot of use out of them before we stored them over winter. Not really used them a great deal this year as we moved house and work is on going with builders etc. I’ve done about 280 miles and she’s done about 200. I have noticed the rear brake is much stronger than the front, don’t remember it being like this when we bought them, it works but the rear stops the bike quicker. As there both Hydraulic discs there is no adjustment as far as I can see, I can’t see any fluid leakage either. What should I look for if three is a problem. Taking it back to shop is not an option, as it won’t fit in the car, and no longer easy for us to get there, Any advice appreciated
there may be a bit of dissolved air in the brake fluid that will separate over time and collects in the reservoir at the handlebars. It's quick and easy to check: squeeze both brake levers, if one feels spongier than the other, that is an indication.
 
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Amoto65

Esteemed Pedelecer
Jul 2, 2017
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Hi, put an elastic band around the front brake lever and the handlebar so it is pulling the brake on and leave it overnight, this usually gets rid of the air in the system. Steve...
 
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Danidl

Esteemed Pedelecer
Sep 29, 2016
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We bought a couple of Wisper 705t bikes about a year ago, both very happy with our purchase. Didn’t get a lot of use out of them before we stored them over winter. Not really used them a great deal this year as we moved house and work is on going with builders etc. I’ve done about 280 miles and she’s done about 200. I have noticed the rear brake is much stronger than the front, don’t remember it being like this when we bought them, it works but the rear stops the bike quicker. As there both Hydraulic discs there is no adjustment as far as I can see, I can’t see any fluid leakage either. What should I look for if three is a problem. Taking it back to shop is not an option, as it won’t fit in the car, and no longer easy for us to get there, Any advice appreciated
Hydraulic brakes do need adjusting, just not as often. In the case of my Magura fitted to a Motus, I found that the front brake needed to be pulled until the handle was just touching the handle bar,after 1000miles in order to get braking. The solution was very simple, looked up on Google and then just twisted an Allen nut about 1turn and all sorted.
 

denwyn

Esteemed Pedelecer
Aug 17, 2013
414
41
Thanks for all the advice, ill try the ones which don't need the pads removing first. If I need to remove the pads for cleaning, are they easy to get out, or should I get local bike shop to do it. They don't do anything with the motor / electrical stuff on these bikes but I take it most disc brakes are fairly standard. We were hoping to get a lot more use out of these bikes this year, but constant problems with builders etc on new home looks like we will not be able to, I would like to sort this out before we put bikes away till next spring.
 

flecc

Member
Oct 25, 2006
52,819
30,381
I would like to sort this out before we put bikes away till next spring.
If you put the bikes away long term, be sure to recharge the batteries every two months, no longer. If lithium batteries are left long term and discharge to empty the cells can fail, leaving the battery useless.
.
 

Trevormonty

Esteemed Pedelecer
Jul 18, 2016
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NZ
Don't store them fully charged. 60-80% is ideal. Best to fully charge and take for 30minute ride to bring them back to 60-80%.

If you put the bikes away long term, be sure to recharge the batteries every two months, no longer. If lithium batteries are left long term and discharge to empty the cells can fail, leaving the battery useless.
.
 

flecc

Member
Oct 25, 2006
52,819
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Don't store them fully charged. 60-80% is ideal. Best to fully charge and take for 30minute ride to bring them back to 60-80%.
Ideally I agree, but I recognise that it might not always be possible. There's no great harm in them being fully charged, the BMS gradually bleeds down the charge.

Below from Battery University are capacity reductions at the temperature stated, the first figure at the ideal of 40% storage charge, the second figure at full charge:

0°C.......... 98% (after 1 year)........... 94% (after 1 year)

25°C........ 96% (after 1 year) ...........80% (after 1 year)

You can see the losses are not huge. Denwyn is speaking of less than a year storage and the average temperatures in the UK, assuming out of the house, will be far below 25 degrees C. The difference between the full charge storage loss and the loss that occur in normal usage will be quite small, especially since the full charge will be continuously declining due to BMS drain over each two month interval between storage charges, dropping substantially.
.
 

denwyn

Esteemed Pedelecer
Aug 17, 2013
414
41
Thanks for all the reply's, things been a bit hectic with lots of work being done in house. I am going to have a go at the brakes this weekend, will try Neal's solution first with the isopropanol when I find somewhere to buy it, are the pads easy to get out ?. Re the comments on the battery, I did put them on charge a few times while we didn't use the bikes, the bikes were stored in garage, which is well insulated against the cold weather, I'm sure the batteries are fine. Its just not been possible to use the bikes as much as we would like to have, but hoping the work on house will all be complete by middle of July and we can get out more on the bikes around were we live. Did think about taking them on holidays but I'm not keen on bike racks on cars at all, looked at buying VW van but far to expensive, there is enough for us to do locally which we will enjoy.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Your local pharmacy should have some 250ml bottles about £3 or £4, otherwise ebay.

To remove pads unbolt the caliper (allen key) and then pads will likely be retaind by a split pin or allen screw, refiitng is the reverse and simple.
Before tightening up the calliper bolts fully, make sure the calliper is still a little slack and pull the brake levers to centralise pads/calliper. Tighten calliper allen bolts then release brake lever, spin wheel to make sure brakes dosen,t bind or rub. If they do slacken calliper and repeat procedure with brake lever before tightening again.
 
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Wynne0648

Pedelecer
May 12, 2017
56
19
Leeds
First time I’ve managed to give this a go, removed calliper and pads, cleaned pads and disc. Not really made any difference. Have pulled leaver back and restrained it with cable tie now to see if that works. Should I also consider bleeding the brake, I see kits on EBay, looks straightforward to do. Is there a special fluid, kits seem to come with fluid, just wondering if it’s standard. Failing this I’ll take bike to local Halfords or bike shop. To much hassle to take it back to we’re I bought it, can’t get it in car.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Brakes shouldn't need bleeding if there is no leakage or air has got in the system, Only time I have bled them is for a calliper, lever change or new hose/shortening.

Some use DOT 4/5 brake fluid whilst all Shimano use mineral oil as may some other brands.
 

chris_n

Esteemed Pedelecer
Apr 29, 2016
656
399
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Niedeau, Austria
First time I’ve managed to give this a go, removed calliper and pads, cleaned pads and disc. Not really made any difference. Have pulled leaver back and restrained it with cable tie now to see if that works. Should I also consider bleeding the brake, I see kits on EBay, looks straightforward to do. Is there a special fluid, kits seem to come with fluid, just wondering if it’s standard. Failing this I’ll take bike to local Halfords or bike shop. To much hassle to take it back to we’re I bought it, can’t get it in car.
Cleaned them with what? Cleaning pads is a waste of time, get new ones. Whatever is contaminating them will have soaked in, you may remove some of it but in time the contaminant will leech out again. Agree with Nealh brakes don't need bleeding unless they have boiled (unlikely) or been opened (or maybe with some pulling the lever with the bike upside down).
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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If pad soiling is light from road grime, I have successfully cleaned them by rubbing washing up liquid between the pads and rinsing other wise agree yes replace them.
Spongey brakes can occur if a bike is up ended, a few do this to mend punctures etc. Air in the reservoir will travel to a high point either calliper or somewhere along the line, once the bike is righted a few actuations of the lever can force the air back up or holding the lever on overnight can do the trick.
 
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denwyn

Esteemed Pedelecer
Aug 17, 2013
414
41
Cleaned them with what? Cleaning pads is a waste of time, get new ones. Whatever is contaminating them will have soaked in, you may remove some of it but in time the contaminant will leech out again. Agree with Nealh brakes don't need bleeding unless they have boiled (unlikely) or been opened (or maybe with some pulling the lever with the bike upside down).
Cleaned them with washing up liquid as recommended and lightly rubbed them with some sandpaper. There was a very slight improvement, which has now disappeared, they do stop you , but the rear brake is 100 times better, bikes only done about 278 miles, its a Wisper 705 T I bought it along with one for partner a year ago, not really been used tat much was put away for winter months, we then moved house and the last 8 months we have been working flat out on major work on house. I wont bother bleeding the brakes as this does not seem to be required from what I am now told, if I can find a stockist for brake pads ill but a set of new ones and try that. Bike stops reasonably quickly but I'm sure its not as good as it used to be, her bike ( same as mine ) is better. Thanks for all the advice.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,135
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West Sx RH
Resin/organic pads offer the best bite force imho.

It could be that your reservoir is low and air is being drawn in, certainly worth checking fluid level.
 

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