can I use V brakes on a 350/500w FRONT HUB conversion kit ?

Hi does any body know if I can use safely V brakes on a MTB when fitting a 350/500w FRONT HUB conversion kit or do I need to change to DISC brakes, I would of thought if I cut the motor or limit the PAS on the controller I could remain with using V brakes, any advice please to help if needed powered by 36v either 10 or 12AH lithium Battery

There are good v brakes & poor v brakes...

 

There are good disc brakes & bad disc brakes.

 

Good v brakes will be a hell of a lot better than poor disc brakes.

 

The prime advantage of discs is that they're out of the mud & standing water - Most of the time.

 

Then there's hydraulic discs. I've got them

Thanks any suggestions as to what V brakes are best or to fit currently have TECKTRO fitted

I have recently gone from average discs, to good V brakes. I absolutely agree that good V brakes can be pretty good. As an example, with my current v brakes I can lock the back wheel flat out, down hill, without shifting my weight. I'm not a small bloke, and I'm riding on fat (2.3 in) slick tyres. Hydraulic discs are another kettle o fish.....

Thanks any suggestions as to what V brakes are best or to fit currently have TECKTRO fitted

Lots of brakes are tektro ones that have been rebranded. Is more about keeping the rims clean of muck, cables tight but smooth and picking good brake pads. I find tektro brake pads to be awful but tektro brake levers and brakes to be good(I won't actually buy any other levers). Clarks triple ones are a minimum imo, £5 a pair from wiggle/chainreaction/evans/halfords/planetxbikes/ect.

The reason for my asking is that I am in contact with a supplier in China that has told me that my bike with current brakes is not suitable and suggesting I buy the lower 250w kit instead of my desired choice of 500w equivalent to 350w hub, need it for bad weather such as head winds, heavy rain and hills in my area. Getting the impression they only want to sell me the legal 250w UK and not the 500w, surely as a customer I can make that calculated choice ......... can't I ? after all I consider myself a sensible rider when speed is concerned.

clockwise beat me to it!

I agree . Good pads, lubricant on the cables and levers but NOT on the rims.

I'm happy going down a 10% with v brakes. I'm not happy going up but that problem wouldn't be helped by discs.

keith

I've always preferred v brakes on a bicycle. I like the simplicity of them and its a lightweight braking system. I've also never felt them lacking in braking power. I specifically bought a lower spec bike last year because it had v brakes and not discs, and i'm glad I did, as it made it easier to fit my ebike kit to it.

I can understand the need for hydraulic disc brakes in extreme biking like downhill mountain biking, at high speeds in wet & muddy conditions.

Front hub motors and disc brakes both work the spokes hard, so V brakes more than halve that stress.

hydraulic brakes for me, well worth the extra money.

The reason for my asking is that I am in contact with a supplier in China that has told me that my bike with current brakes is not suitable and suggesting I buy the lower 250w kit instead of my desired choice of 500w equivalent to 350w hub, need it for bad weather such as head winds, heavy rain and hills in my area. Getting the impression they only want to sell me the legal 250w UK and not the 500w, surely as a customer I can make that calculated choice ......... can't I ? after all I consider myself a sensible rider when speed is concerned.

I'm a sensible rider too but emergency stops aren't always upto me. With a larger motor you could be getting yourself upto 30mph(I'm sure you can find some guy doing it on youtube) and stopping doesn't happen for a good few yards at that speed, in the rain and downhill even more than a few yards. I personally think unless you are spending loads on discs then well maintained v brakes are just as good, both have thrown me over handlebars in the past.

 

Remember the supplier has no idea what you are converting, I wouldn't give a blanket "ok" to all brakes being safe after a conversion and with discs you don't get so many varying degrees of working. Lots I have noticed get a sub £100 halfords special bike that might already be a year or 2 old and then strap a motor too it then wonder why it's not as good as they expected.

 

Brakes aren't too expensive, shop about and you can have new everything(pads, brakes, levers, cables, tools) for £20-30 and maybe take an hour or 2 to fit them all up.

 

Tektro M15 V-Brake

Clarks Elite MTB V-Brake Pad

GT85 Spray Lube + PTFE / 400ml

Clarks Universal Galvanised Brake Cable | Chain Reaction Cycles

+ poundshop pliers to cut cable

 

If you need help then I can point you in the direction of suitable youtube videos about adjusting/fitting brakes. You might want to have someone more pro check them the first few times but after a while it will be 2nd nature.

Clockwise

 

Thank you so much for that input that would be much appreciated if you could send me those You Tube video links on adjusting/fitting

Clockwise

 

Thank you so much for that input that would be much appreciated if you could send me those You Tube video links on adjusting/fitting

Here is part 1 of I think 6 by bikemanforu on V brakes, more practical than some of the others as he fixes dirty broken looking "real" bikes instead of fresh new looking things.

 

Brake Noodle Install - Broken V Brake Part 1 - BikemanforU DIY Bike Repair Tutorial - YouTube

 

Global cycling network also have some good videos, here is the one on swapping brake pads and a link to a playlist about all sorts of stuff. Tends to be more racing bikes and high end stuff but the mechanics side of them are the same.

 

 

[video=youtube;usIoHuWeaJM]

 

Have a look at other videos by them are plenty on all sorts.

 

If you are unsure then get a shop to check it.

Thank you for that well this was the reply from supplier in China it reads :

Thanks for your email. it is our pleasure being service for you.

 

we have 36V500W front motor can supply to you, although it is Dick brake type, but we think it can be used in V brake type.

 

Our motor have speed sensor and 9 pin waterproof connectors, but it does not mean all ebike systerm are waterproof. The waterproof grade is IP54.

 

Also another reply : I notice that your your gear shifter and the brake is combined so I would like to recommend our power-cut off switch for you.

 

Your gear shifter can't be replaced by a power cut-off brake because it is combined with the brake lever. It has nothing to do with the V brake or the wheel.

 

So am I ok to NOT use the brakes they supply with the kit? and keep to my own using quality V brakes or do I need to fit brakes provided.

 

Any help appreciated photos of the bike are at :

 

http://www.pedelecs.co.uk/forum/electric-bicycles/16085-how-easy-make-e-bike-out-conversion-kit.html scroll down to No.4

 

Thank's guy's

T

we have 36V500W front motor can supply to you, although it is Dick brake type, but we think it can be used in V brake type.

 

Thanks for giving me a chuckle :o

 

Made my eyes water.

My reading of the Chinese message is that the hub has the holes drilled to fit a disc, does not impede use of rim brakes in any way and he's not saying you need or require discs.

 

I use throttle control only (so not pedelec) and don't bother with the brake cut offs. That saves you using their cheap brake levers.

IMHO disc brakes are necessary if you're going to use a 350w or 500w motor and its associated heavy battery. Rim brakes are OK on light-weight electric bikes up to 15mph.

 

Cable disc brakes often get a bad reputation because they're not properly adjusted. I've never seen a set yet that came from the shop OK. They require a lot more adjustment than hydraulic ones, but a lot less than rim brakes. Another important point is rim wear. If you look on Endless-sphere. you'll see several instances of rims worn so far through that they can't hold the pressure from the tyre, so they pop off with catastrophic results. This sort of wear takes a long time on a normal bike, but it's different on a high speed/power electric one.

 

The bloke from BMSB was saying that you can't use the kit's e-brake levers with your bike because they replace your existing ones leaving you without gear-changers. You therefore need in-line brake sensors, like their Hidden Wire Brake Sensors as an additional item instead. There's no reason that you can't choose disc or rim brakes with that motor.

 

A 250w motor is OK on the front, but if you want a high torque motor like the Bafang BPM, it would be better to fit a rear one.

 

You mentioned a 10 or 12aH battery. There's not many that have enough power for a 500w motor.

d8veh

 

thanks for that advice can you point me in the right direction for the in-line brake sensors you mentioned like where do I purchase them and where do I fit them exactly ? any images or guides out there would be a help as not sure where they would go as regards the motor yes it will be 350/500w category but only being used when tackling say head winds and hills or other elements. Thank's again

Which ones to get depend on where you buy the rest of the kit. I get my stuff mainly from BMSBattery, so that's where I'd get them from at the same tine as the motor so that the shipping is free.

 

Here's the BMSB ones. They just slide over the cable. You need to shorten the cable outer by about 50mm:

HWBS - Hidden Wire Brake Sensor 1pcs - BMSBATTERY

 

There's these cheap ones with mechanical switches. They go at the end of any exposed part of the cable. No need to shorten the outer. Simple to install if you have two-wire connectors on your controller, but you need to keep your brakes properly adjusted. They're not set-and-forget:

Aliexpress.com : Buy electric bike brake sensor popular in Holland, Germany from Reliable sensor car suppliers on Golden Way Cycle (Hangzhou) Co., Ltd.

 

These ones are similar to BMSB ones, but might work out cheaper if you got your kit elsewhere. You have to buy four, but the price is still OK even if you only use two:

Aliexpress.com : Buy Brake sensor for ebike from Reliable sensor light suppliers on Suzhou New Power Co.,Ltd.

 

Have you decided yet which motor and battery to get and where to get it from?

 

http://i451.photobucket.com/albums/qq236/d8veh/Misc%20bike%20stuff/Chinese%20stuff/kitrear_zpsb1ca40d3.jpg

hi yes this is the company : Changsha 301 New Energy Co., Ltd. known as TNA brand and found on ALIBABA.COM and have mailed them regards in line sensors as an enquiry the 36V x 500 brushless Bafang BPM FRONT MOTOR with speed sensor and waterproof connector and the battery is 36v x 12Ah POLYMER LI-ION black tube battery - controller is a 12 mosfets and finally the charger is a2 Amps aluminium shell for lifepo 4 48v battery they are providing a thumb throttle but I much prefer a half twist with red button. So your thoughts and suggestions on what I have chosen and will it do the job or recommend any suppliers that will? Are Polymer batteries like the one chosen one of the best or just hype at the end of day as I currently have on my E bike 36v x 16Ah Lithium Ion

Edited November 13, 201312 yr by bayrider

That doesn't make sense. The charger is for a 48v LiFePO4 battery, but you will have a 36v one!

I've never seen a 12aH tube battery before. Ask him how many cells and what type are in it. If it's 50 cells, it probably won't fit in your frame. Unless that battery is something special (expensive), it won't be able to supply enough current for a 500w BPM either.

 

Read this before fitting a front 500w BPM:

 

Endless-sphere.com • View topic - Bafang BPM 500W broke again the aluminium fork dropouts

 

What bike will you be fitting the motor to?

the bike I am fitting to is MTB GIANT BOULDER link can be found in this thread it is a bottle shape and have measured up and seems ok. The spec is:

 

Specification:

1.Model: 36V12AH tube type(Polymer lithium ion cells)

2. Voltage : 36V

3. Capacity: 12Ah 0.5C Discharge

4. Max Charging voltage: 42V

5. Discharging cut-off voltage : 30.0V

6. Max charging current :2A

7. Continue discharging current :15A

8. Peak current: 30A

9. Lifespan : 600 Cycles >capacity 60% 0.5C

10. Available capacity : >96% (30.0V cut off)

11. Weight (Approx) :3.2KG

12. Dimension: 92*370mm

13. Charging temperature: -10°C to 55°C

14. Discharging temperature: 0°C to 45°C

15. Storage temperature: 10°C to 30°C

 

 

Characteristics:

NO. Item Requirements Test Method

1 Discharge

Characteristics Discharge capacity

Nominal capacity×100%

A)0.2C5A ≥100%

B)0.5C5A ≥98%

C)1C5A ≥95%

Standard charge at 0.2C5A under the condition of normal atmospheric pressure and the environmental temperature of 25°C±5°C and 45%~80% RH(unless otherwise specified, storage and charging should be conducted as this regime), then rest for 10min and discharge at 0.2C5A,0.5C5A,1C5A to 30V respectively. Charge/discharge cycle can be conducted for 3 times before meeting the Standards(the same below).

2 Normal Storage Residual Capacity≥Nominal capacity*85%

Recoverable capacity≥Nominal capacity *90%

OCV decrease≤3%

impendance increase ≤20% Measure initial status and initial capacity. Store for 28 days after standard charge, then measure final status and residual capacity at 0.2C5A to 30.0V; After charge/discharge(1C/0.5C) cycle can be conducted for 3 times , measure the recoverable capacity before meeting the Standards(the same below).

3 Cycle Life Discharge Capacity≥Nominal apacity*60% 0.5C discharger

Measure initial status and initial capacity, then conduct 0.5C discharge cycle for 600 times . Measure last status and last capacity 60%

 

 

Safety Performance:

NO. Item Requirements Test Method

1 Over charge No fire,no explosion After standard charging,then Charge at 3C5A to 10.0V

2 Over discharge No fire,no explosion

After standard charging,discharge 0.3C5A to 0V

at 20°C±5°C

3 Drop

No fire,no explosion

no leakage

After standard charging, then let it self fall off from

a height of 1.5m(the lowest height)to a rigid wooden

board with the thickness of 20mm. The drop is

implemented one time for every face.

4 Hot Oven No fire,no explosion

After standard charging. Keep the battery in the box

with constant temperature of 85°C±2 °C and

remained for 2hours at this temperature.

5 Crush No fire,no explosion

After standard charging, keep the battery

on the bracket

1. Extrusion direction:Perpendicular to the direction

of maintaining pressure on the battery plates.

2. Extrusion headdress product:≥20cm

3. Extrusion degree: Until the battery shell ruptured

or internal short circuit (battery voltage becomes 0V)

6 Needle

puncture

performance No fire,no explosion

After standard charging, keep the battery on the

bracket,penetrate through it with a 3mm~8mm

diameter nail near the center of its biggest surface

at the rate of 10mm/s-40mm/s.

 

Charger Specification:

AC Voltage: 110~240V

DC Voltage: 43.8V

DC Current: 2Amps

Dimensions: 51*93*160mm

Net weight: 0.9kg

Features:

1. Short-circuit protection; Charger O/P cut-off automatically when short circuit.

2. Overload protection: Charger O/P current-limited automatically when overload.

3. Reverse polarity protection: Charger O/P cut-off automatically when battery reverse connection.

4. Automatic multi-rate charging function: CC,CV,Cut-off .

5. Parallel operation available: Parallel with battery as DC power supply operation available.

2 LED Display: LED1 Red(power on); LED2 Red(charging); Green(full).

 

So what do you think ? any other forum members have any views on this project ?

d8veh

 

regards the in line sensors (HWBS) do I need to buy 4 do they go on each side both front hub end and rear wheel or only 2 and where is the best place to place them for use, any thoughts on the last update with the data spec or am I best off going for the battery but lesser hub power say 350w or 250w?

Is it a sideways mounting one or vertical. If vertical, you need space to lift it off/on as well. The one in the photo below just fits. If it were 5mm longer, it wouldn't. You can see that it's not just the length you need, but the space above it.

 

12FET controllers are normally around 30 amps, so you'l be pushing that battery hard, but it might be OK.

 

http://i451.photobucket.com/albums/qq236/d8veh/Oxydrive/oxybike.jpg

hi it is exactly the same as the photo you supplied I have just found a kit. Well I am confused now as just stumbled across this on Ebay : Specification:

* Power: 500W / 36V . ..... .. * Max speed: 35 km/h........* Net weight: 10kg..

* Wheel type: front .... .... * Wheel Size: 26"...... .....* Max load capacity: 85kg....

* Motor: Brushless gearless ..* Torque: 35 N.M .. ....... .* Spokes: Steel, 12G×2.6mm

* Tire: Nylon .......................* Rim: Alloy double wall .......

Key feature:

* Built to the highest international standards, CE, EN15194

* Wheels using double wall CNC rims and heavy duty spokes

* Rare-earth metal magnates are used in the motor to efficiently produce large power

* Thumb throttle has battery level display and power-cut off button

* E-brake handles are integrated into the wiring loom for power-cut off safety

* Male/female plugs are unique to avoid any confusion when connecting

* Motor hub has disk brake mounts

* Crank speed sensor for pedal assist

* Aluminum alloy powerful controller

* One ring placed between thumb throttle and handle bar

Note: 1.Our products are compatible with many kinds of battery. 2.Battery is not included.

Package Includes:

1x Brushless Gearless Motor Front Wheel

1x Intelligent Motor Controller

1x Pedal Assist Crank Sensor

1x Cable Ties & Plastic Coil

1x Thumb Throttle

1x Pair of Handle Bars

1x Controller Bag

1x Pair of Brake Handles

1x Instruction

 

 

it will save me about £120 even with tax ect from china but will need to source a bottle shape or similar to fit to slant of frame 36v 12AH battery, would I be best off sourcing from the EU or China bearing in mind I would need a suitable charger too! shipping and taxes and handling charges.....what shall I do? also do you you think the controller be an issue with this battery? you mentioned it would take 30Amps

Edited November 13, 201312 yr by bayrider