Mechanical disk or hydraulic disk for fast bike

flik9999

Pedelecer
Dec 11, 2016
164
29
33
london
Hey so I went and bough a bafang bbso1 250w, I plan to overclock this and hear that you can get speeds up to about 28 mph.

For these kinds of speeds do I need hydraulic discs or would mech ones be good enough, I already have the fork, rotars and normal levers. I can grab the Avid BB7 for £25 from ebay or if I want hydraulic I can get the TRP hylex which is a single speed hydro disc.

BB7s will be cheaper but will it be strong enough for this sort of job. Im thinking of capping the bike out at 25 MPH as thats a believable speed for a race bike to go at.

Also dont care about the law, I seriosly doubt cops in london are checking bikes with the amount of 1000w bikes iv been seeing around my area. I ride at about 20 mph with my current weak bike, they must be going much faster.
 

Baboonking

Pedelecer
Nov 4, 2006
147
6
Watford
I have hydraulic brakes, I don't think the breaking is any better than mech disks but the modulation is better and they feel nicer to use. At routine speeds of 25+ mph suspension will save a lot of bike wear joint wear.and also might save you from coming off the bike. It's quite a different experience riding 25mph all the time than doing the occasional 25mph + down a steep hill like on a normal push bike, because your thinking oooh this is fast be careful. 25mph ebike that's just your normal speed.

Re the law, yeah I've not heard of anyone getting caught for riding a modified illegal ebike but if you crash and hurt yourself be ready for questions from your personal injury insurance or if you hit someone else then you could be charged with riding an unlicensed motor vehicle and could do prison time. Similar case

https://www.theguardian.com/lifeandstyle/2017/sep/18/cyclist-charlie-alliston-jailed-for-18-months-over-death-of-pedestrian
 

Baboonking

Pedelecer
Nov 4, 2006
147
6
Watford
I find any disc brakes give you more control, but perhaps that because I was not in the habit of adjusting my pads all the time. Disk brakes are definitely better in the wet.
 
D

Deleted member 4366

Guest
Don't waste your money on BB7s. They can't hold a light to proper branded hydraulic brakes. When you first install them they can match the braking, but they're not consistent. I can't understand why people keep recommending them unless it's because they never used proper brakes.

Hydraulic brakes are self-adjusting, so need no maintenance other than pad replacements when they wear out, which is normally at something like 2000 to 5000 miles.

You can get hydraulic brakes for the same price as BB7s too.
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,592
1,747
70
West Wales
Front hydraulic, rear mech. The feel and braking power of the hydraulic is far superior. And there's no fiddle with them.
If you are averaging that sort of higher speed you need the stopping power, especially in traffic. Why dick about with your life for the sake of a few quid?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
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West Sx RH
Front brake will always feel superior if it is working properly ( no contamination, worn brake surface) provides about 70% + braking effort. Pad material and disc compatibility makes a difference for improved performance, I prefer the bite feel of resin /organic compound on my bikes and pads can be sourced quite cheaply. Even in the wet bite is very good.
Cheap unbranded ones £1 or so a pair from China work well as do the BrandX ones, needing only one quick centralising op when refitting no other adjustment or bleeding required.
All my bikes run Shimano m395 or m445 range of brakes, levers and callipers are all basically the same and are twin actuated.
 

awol

Esteemed Pedelecer
Sep 4, 2013
1,216
374
Pad material and disc compatibility makes a difference for improved performance
Do you mean the actual disc can make a difference? If so is there any particular styles you recommend to match your brakes+pads.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
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Some discs/rotors have resin or resin only or similar etched on them, generally I just but a rotor for under a tenner. Have tried sintered but the bite was poor on my discs so stick with resin/organic compound for the reassuring stopping power, light pressure is all that my set ups require if I grab the lever to hard I get lock up.
Although the bias is always to the front 70/30 0r 80/20, it's always nice to feel the rear biting well.
If hdb's bite is vague then look at disc compatibility, pad compound or contamination of both surfaces. Air in the system can only be due to a leak of if you often turn the bike upside down, in which case you need to let the bike stand for a while in the upright position for air to rise.Loosening the lever to horizontal plain and actuating the lever a few pumps will also remove air, if you remove the reservoir cap and it is full you can see any trapped air rising. As long as the lever actuation is firm with no spongey after travel then air isn't an issue.
 

Gringo

Esteemed Pedelecer
Jun 18, 2013
1,346
842
Northampton
I've used shimano m315 hydraulic on a recent build, front and rear new for £36 off the bay, I can't see any reason why anyone would want to use mechanical brakes, unless they came fitted on a bike :rolleyes: even then I'd recomend switching to hydraulic ;)
 

Trevormonty

Esteemed Pedelecer
Jul 18, 2016
1,135
564
17
NZ
With cable brakes you need lot more effort to overcome cable stretch and resistance than hydraulic brakes. The rear cable disc brake on my old bike required lot more effort than M355 on new bike.
Hydraulic need bleed very occasionally for most bikes and riders never, cables need regular adjustment as pad wears and lub of cable.

Shimano M355 €30 a pair while more powerful M6000 with larger G02A pads are €75 pair from bike discount. M355 (BS01 pads)is good reliable brake, but there is significantly better performance with my XTs and the larger G02A pads. Go for 180mm disks both wheels, check if wheels will support M6000 disks. You will need bleed kit as levers may need swapping, euro front is left side.
 

Trevormonty

Esteemed Pedelecer
Jul 18, 2016
1,135
564
17
NZ
Excellent brakes are useless if tyres don't have traction to support it. At these speeds good tyres are a must, fat city tyres ideally with very soft grippy compound front tyre. You may have to trade puncture resistance for safety here.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
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West Sx RH
The m315 thru to m495 and some in the m500 range, generally offer good braking performance at a cheaper but more affordable price. All that use B01S pads the calliper is uniform and generically totally interchangeable mostly the only difference is in the lever. With 5 bikes all use B01S pads except the Swizzbee rear which has HS33 from Magura. The only time I've a had to bleed any is a for a broken lever or shorten a brake line.
 
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anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
7,845
5,786
The European Union
Twin SA 90mm hub brakes on my new ride. I was a little worried about them at first but they are fine on 24% downhills :D More expensive trikes have hydraulic disks but the fastest pedal powered rides on earth (vélomobiles) mostly use the SA hub. I have learnt that on each ride you need to brake hard just after leaving home to seat the brake pads or clean the interior of the drum after that they are as smooth as silk.
 

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