I've just bought a Freego Eagle e-bike, really to upgrade Sally's Wisper 705SE, but having ridden it the eight miles home,  I'll be quite happy if she doesn't want it - 15ah battery + Grandfather regs full throttle = loads of fun 😁

 

But the rear disc brake was shockingly poor, which I presumed was just cable adjustment - it wasn't.  Somebody has rounded one of the allen headed calliper retaining bolts.  It's not a problem, I'll pop out for a new one later.  The disc was a bit grimy, so I wonder if it's contaminated, along with the pads - there was a bit of copper grease on the outside of the calliper.

 

The reason for the poor braking was at least in part down to the fixed brake pad adjusting screw being backed off too much.  Having now adjusted it up, centred the calliper and much improved the braking, I'm fascinated with how the calliper works.  With a fixed brake pad, adjusted in to close proximity to the disc, does the braking rely on the the moving pad forcing (i.e. bending) the disc onto the fixed pad?

 

It just seemed odd dynamically, and I couldn't work out if there was something else going on that I couldn't see.  This is my first foray into cable disc brakes - my Whyte has hydraulic ones where both pads move onto the disc.

 

Gaz

 

1 hour ago, Gaz said:

I've just bought a Freego Eagle e-bike, really to upgrade Sally's Wisper 705SE, but having ridden it the eight miles home,  I'll be quite happy if she doesn't want it - 15ah battery + Grandfather regs full throttle = loads of fun 😁

 

But the rear disc brake was shockingly poor, which I presumed was just cable adjustment - it wasn't.  Somebody has rounded one of the allen headed calliper retaining bolts.  It's not a problem, I'll pop out for a new one later.  The disc was a bit grimy, so I wonder if it's contaminated, along with the pads - there was a bit of copper grease on the outside of the calliper.

 

The reason for the poor braking was at least in part down to the fixed brake pad adjusting screw being backed off too much.  Having now adjusted it up, centred the calliper and much improved the braking, I'm fascinated with how the calliper works.  With a fixed brake pad, adjusted in to close proximity to the disc, does the braking rely on the the moving pad forcing (i.e. bending) the disc onto the fixed pad?

 

It just seemed odd dynamically, and I couldn't work out if there was something else going on that I couldn't see.  This is my first foray into cable disc brakes - my Whyte has hydraulic ones where both pads move onto the disc.

 

Gaz

 

Hi Gaz, I think that is the way the fixed brake pad is supposed to work -  correct gap would be critical.

Cheers Warrior - gap is critically correct, calliper lined up nicely with the disc, so everything's operating as I think it should.  Just seems a bit inefficient that some of my effort at the brake lever and through the cable, is put into bending the disc.

 

I quite like that it's all adjustable with a multi-tool when we're out and about.

 

It's a great bike, very comfortable all round.  I'm quite sure if I'd moved the throttle over to the left side, I wouldn't have had to pedal at all on the way home.  Was 25c when I got home and felt hotter out on the Marshes.

 

Gaz

 

Cable brakes are really poor from an efficiency point of view because as you realise most of the effort goes into bending the disc! Being the rear they don't do much (10-15%) so once you've got correct clearance, clean pads and discs it will take ages to wear out the pads, though adjustment might be every few weeks depending on mileage, (with (hydro) brakes I get 1 rear to 3-4 front pads on an acoustic road bike).

Thinking it through, it'd make sense to move the calliper as close to the moving brake pad as possible, without it fouling the disk, then adjust the fixed pad into the disc, that way I'd be reducing the amount of movement at the moving pad and therefore giving more useful travel (i.e. less non-useful travel) at the brake lever.  Time to get a replacement bolt first methinks.

 

G

Edited 9 July, 20223 yr by Gaz

I'd be looking at replacing with hydraulics.....tektro or clarks can be had for peanuts, frisking ebay usually comes up with plenty of others as people upgrade.

I replaced my Whytes with Magura so I do have 2 calipers/levers but the thought of selling on eBay means they are sitting in a draw

I’ve just mullered the other calliper bolt 🤬 Luckily I had the foresight to buy a pair.

 

As a Brucie bonus it turned out the battery was replaced last year 👍 They say size doesn’t matter, but look at it next to my 11.4ah E6010 battery - no wonder the grunt is noticeable:

 

 

Gaz

Cheap cable disc brakes are generally awful even when adjusted perfectly in my experience. There are better ones like TRP spyres that do move both pads at once but they are still not great. Next step is hybrid hydraulics like TRP HY/RD or Juin tec whch have hydralic calipers actuated by a cable. They are another step better but really, you know where this is heading...... 🙂 

 

Full hydraulic is the way to go really. My preference would be for Shimano but really even inexpensive Clarks or similar will be an improvement and be less maintainance.

 

 

1 hour ago, edwards said:

.... but really, you know where this is heading...... 🙂 

 

 

 

Those on my Whyte are Shimano and they are indeed worlds apart.  I'll see how 'we' get on with the current set up (bike still hasn't had the green light from Mrs Gaz yet), but yes, I might well be heading you know where.... 

 

If I do, I might well ask a LBS to do it as the cable run goes through a few retaining tubes, which means, if a want it to look right (and I do), separating the hydraulic pipe so it can be passed through unhindered.

 

Gaz

18 hours ago, Gaz said:

 

.....If I do, I might well ask a LBS to do it as the cable run goes through a few retaining tubes, which means, if a want it to look right (and I do), separating the hydraulic pipe so it can be passed through unhindered...

 

totally - best to have it look right and have the correct length hoses etc. That said, its actually pretty easy to shorten and bleed shimano brakes yourself if you want to - youtube is your friend 🙂