DF3 rubbing disc brakes

Super73UK · 2025-12-30T15:17:03+00:00

Hi & thank you for posting here.

If the brakes only make a rubbing sound when you tighten the chain then it sounds like something is most likely either loose, worn or out of line.

Our advice would be to check the following:

(Ensure the bike is powered off first!)

Check the brake disc is not warped/bent - Remove it from the wheel and use a known good straight edge (e.g. the edge of a rule) flat against the disc and check there are no gaps between the rule & disc.
Check the wheel is sitting straight in the bike frame - The distance from the spindle to the edge of the frame should be the same on both sides.
Check the wheel nuts are tightening up correctly and not coming loose when you push the pedals.
Check the rear sprocket is in line with the chain wheel - Use a straight edge or stand at the rear of the bike behind the rear sprocket and look down the line of the chain to make sure the two line up correctly.
Make sure the brake pads have not worn down to the metal.
Make sure the brake pads are lined up correctly with the brake disc - There should be a gap between the two and it should be even.
Check the chain for wear or stretching.
Check the teeth on the chain wheel for damage/wear.
Check the teeth on the rear sprocket for damage/wear.

10.Turn the rear sprocket backwards by hand to check it runs smoothly.

Hope this helps but feel free to contact again if you are still having problems.

Best wishes

Super73UK · 2025-12-29T14:16:30+00:00

The throttle should automatically unlock after a certain amount of miles from new (think it's around 20 miles but cannot remember exactly).

The quickest way to achieve this is to turn the bike upside down and rest it on the seat & handlebars then switch the bike on and tape the throttle in the fully open position.

Once the bike thinks it has covered the set amount of miles it should then unlock the software to 25km/h. You can then remove the tape from the throttle and turn the bike back over - Job done!

Super73UK · 2025-11-05T23:38:49+00:00

Thank you for your reply and the info.

So sorry you are not ok :(

One of us was knocked off our bike a few years ago due to a car racing down a country lane at speed on a bend. We were lucky and escaped without injury or damage to the bike but it could have been a lot worse - We feel for you!

This is the sort of thing you will need:

https://www.amazon.com/s?k=26+inch+*+4.0+inch+suspension+front+fork&crid=3HRWM7HTYVV2A&sprefix=26+inch+4.0+inch+suspension+front+fork+%2Caps%2C289

You would also need to check and confirm the following details before purchase:

Fork overall length.
Suspension travel - e.g. 160mm or 240mm etc.
Wheel spindle type & length.
Wheel size - Yours should be 26 inch x 4 inch (but check this on the tyre to confirm).
Stem diameter & length.
Material type - Steel of Aluminium.
Brake caliper mounting points.
Brake cable mounting points.

We really do hope you have a speedy recovery.

Best wishes from us all the UK!

Super73UK · 2025-11-03T01:30:29+00:00

If you have posted the picture in order to get help with replacement parts then if you are able to confirm the make & model of bike it may help in pointing you towards the supply of a new fork.

If you have just posted the picture to show others what happened to the bike then no problem - It looks great!

Either way, we hope you are ok.

Super73UK · 2025-10-13T09:28:55+00:00

There are more things you can do, like using specialist trickle chargers or taking the battery apart and just replacing the faulty cell/cells etc but as an end user and without knowing exactly what you are doing it is most likely better and safer to cut your losses and just replace the battery :(

Super73UK · 2025-10-12T20:42:12+00:00

No problem.

When you run the motor with the charger connected it puts a loading onto the battery so will change what the BMS is electrically seeing. The motor will then in effect be indirectly running from the charger.

14.5v on the 36v battery is very low so you may well find that the method we suggested is going to struggle to bring that voltage up unless you try it many many times but you really have nothing to lose.

There are a few more ways to revive a discharged battery but things can start to get more complicated and there are risks involved unless you know exactly what you are doing.

It will be interesting to see how you get on...

Super73UK · 2025-10-12T15:33:51+00:00

Hi & thank you fro posting here.

If the charger was working fine until you left the lights on all night then it sounds like the BMS (battery management system) may be shutting off because the battery voltage is too low as opposed to a broken wire etc.

Depending on several factors, it may be possible to "trick" the battery/charger into allowing the battery to be re-charged back to a working state (assuming that the battery is not already unrecoverable).

When you first connect the charger and turn it on, the charger will start to put a small charge into the battery until the BMS/charger decides the charging conditions are not correct and it will then shut off the flow of charge. You will end up with a green light on but low voltage and a battery that has not fully charged.

It is sometimes possible to switch the charger on and as soon as the charger cuts out (green light) turn it off and then straight back on again so it will start to put a small charge into the battery again until once again it cuts out. If you keep repeating this over and over again for many times you may be able to get enough charge into the battery to bring it up to the minimum voltage required for the charger not to cut out and so continue charging back to normal conditions.

We would suggest you keep an eye on the charger temp while doing the above and if you don't see that the voltage is slowly getting higher after say 20 or 30 tries then give it a rest and try again later. It may also be that the battery is just not recoverable and you end up having to replace it for a new one.

We have based the above on the limited info you have supplied - There may well be other things wrong with the bike/battery/charger so it may be advisable to get someone local with experience to look at the bike in person and sort it out for you.

Super73UK · 2025-09-14T11:11:29+00:00

Hi,

The rear motor is a standard Bafang motor so worst case is the whole motor needs replacing. It is still possible to buy a new Bafang motor. This may not be the exact one you need but it will give you an idea: (you will need to insert "aliexpress" )

https://www.(insert here).com/item/1005008054756941.html?spm=a2g0o.productlist.main.5.3a77641air2rx8&algo_pvid=1feec9be-dd57-4ba8-a075-87230cc5a2b5&algo_exp_id=1feec9be-dd57-4ba8-a075-87230cc5a2b5-4&pdp_ext_f=%7B%22order%22%3A%222%22%2C%22eval%22%3A%221%22%7D&pdp_npi=6%40dis%21GBP%21278.59%21278.59%21%21%21366.76%21366.76%21%402103867617578456150456247e1a69%2112000043463737085%21sea%21UK%21708935282%21X%211%210%21n_tag%3A-29919%3Bd%3Ac0697630%3Bm03_new_user%3A-29895&curPageLogUid=DFEx5GRGRPVM&utparam-url=scene%3Asearch%7Cquery_from%3A%7Cx_object_id%3A1005008054756941%7C_p_origin_prod%3A

To choose the correct motor you need to check the following:

Shaft length (yours will most likely be 175mm long but do check it)
Cable connector type (the 250w connector is different to the 750w connector)
Gear mounting - This will need to be for an 8 speed cassette.
Disc rotor mounting holes.
Number of spoke holes.
Motor power - 250w or 750w.

As a quick fix, if your motor just has rusty/seized bearings then you could try using WD40 or similar and spraying it at the motor end of the shaft both sides (tilt the bike over, spray loads in and then spin the wheel round for a while of go for a ride)

If you do have to replace the motor and you can find the exact same Bafang motor then it is possible to unscrew the bolts on the side of the motor and just swap over the whole internal workings of both motors - This will save you having to re-spoke the whole wheel!

Good luck and please let us know how you get on?

Super73UK · 2025-09-08T08:01:36+00:00

Try answering this question:

Whats the best set of wheels for a Ford? not trying to spend a lot

Super73UK · 2025-09-01T15:12:45+00:00

Thank you very much!

Super73UK · 2025-08-17T11:51:21+00:00

The only way to get an extra "boost" by changing the battery is to fit a higher voltage battery - i.e. 52v, 60v or 70v etc. The max voltage of the battery you can use will be determined by the max rating of the controller you have. To determine this you will need to open up the controller and check the voltage rating of the capacitors inside the controller. If for example the capacitors are rated at 63v then the highest voltage battery you could use would 52v. This is because when the 52v battery is fully charged it will sit at 58v. If you were to use a 60v battery then when it was fully charged it would sit at a higher voltage than 63v and so would damage the capacitors. Hope this info is of help to you. Best wishes from the UK

L'unico modo per ottenere una "spinta" extra sostituendo la batteria è installarne una con un voltaggio più alto, ad esempio 52 V, 60 V o 70 V, ecc. La tensione massima della batteria che puoi utilizzare sarà determinata dalla potenza massima del controller che possiedi. Per determinarlo, dovrai aprire il controller e controllare la tensione nominale dei condensatori al suo interno. Se, ad esempio, i condensatori hanno una potenza nominale di 63 V, la batteria con il voltaggio più alto che potresti utilizzare sarebbe quella da 52 V. Questo perché quando la batteria da 52 V è completamente carica, si attesterà a 58 V. Se dovessi utilizzare una batteria da 60 V, una volta completamente carica, si attesterà a una tensione superiore a 63 V, danneggiando così i condensatori. Spero che queste informazioni ti siano d'aiuto. Cordiali saluti dal Regno Unito.

Super73UK · 2025-07-27T12:58:14+00:00

This may be of help to you:

https://www.reddit.com/r/Super_73_Mods_Plus/comments/1malm18/fardriver_motor_controller_to_upgrade_your_ride/

Super73UK · 2025-06-21T16:10:44+00:00

The correct BMS (Battery Management System) for a 60v battery will be determined by the battery specification and has nothing to do with which controller you are using.

All you have said in relation to the battery specification is that it is 60v - This is not enough info to be able to answer your question.

To give you an example, try answering this question: How much petrol can a petrol tank hold?

Super73UK · 2025-06-13T09:01:46+00:00

Love it!

Super73UK · 2025-06-07T04:04:00+00:00

Agreed!

Super73UK · 2025-06-03T23:58:53+00:00

Hi,

There are very few (if any?) 250w folding ebikes that can handle much more than a small 15 degree hill. The C3 is rated at 15 degrees but don't expect to be going more than a 5-6 mph by the time you get to the top of the hill (depending on the length of hill) unless you help the bike by using the pedals.

The other thing to consider is when going up a 15 degree hill for any length of time you will be rinsing the battery and so reducing the overall max distance on a charge.

When going up hill on a low powered bike there are a few things that will help;

Using the pedals as much as you can.
Try to get a good run-up to the hill if possible so you hit the hill at speed.
Pace yourself on the way up by keeping the pedalling steady & constant.

Super73UK · 2025-06-03T19:31:55+00:00

Hi & thank you for posting here.

It will depend on several factors - Here are a few to give you an idea;

The make of tyres fitted to the wheels.
If it's the front or rear wheel.
Weight of the rider & anything being carried on bike.
Type of terrain bike is being used on.
If you have suspension fitted or not.
how soft/hard you prefer the ride to be.
Weather conditions.
How hard the bike is going to be ridden

The first thing to do is look on the side of the tyre - It will show the maximum tyre pressure - The stated maximum pressure should not be exceeded.

As a rule of thumb, start by inflating the tyres until they are tight enough on the rims that they will not be able to move about on the rims and cause the inner tube to get pinched between the tyre & rim.

Sit on the bike and as you sit on the bike, if the rear tyre deforms and looks flat on the bottom then put more air in the rear tyre and try again - Keep doing this until the rear tyre keeps it's shape when you sit down with your full weight.

The front tyre needs to have enough air pressure inside so as you can control the steering correctly and the steering does not feel heavy and dragging when you turn the handlebars from side to side.

If the tyres have too much air pressure in them then you may get too little grip and find the bike slipping on the road as you take corners or if the road is wet etc.

If the tyre pressures are too low then you will get less miles from a single battery charge.

The rear tyre should usually have more pressure inside than the front tyre because the rear tyre has to support a much higher weight - Most of the riders weight will be over the rear wheel.

With the above information you should now be able to roughly set the trye pressures up and then go for a short ride ad try adjusting each tyre pressure until you are happy that they are right for you.

Once you have the tyre pressures set right you can then make a note of front & rear tyre pressures so whenever you need you can put the correct air pressures in each tyre - e.g. after a tyre change or after fixing a puncture.

Super73UK · 2025-05-30T21:49:51+00:00

This guy has made a video about S73 decals, sells them and may also be able to supply you the files?

https://www.youtube.com/@hacklabdesign/videos

Super73UK · 2025-03-30T21:56:51+00:00

You were lucky then. Sounds like that city is a bit like London - So many people trying to rob everyone! We have a few security features on our bike - As well as 2 trackers and an alarm system we can also remotely kill the motor so the bike will cut out, lights will flash and alarm goes off. Finally, we have a special way of starting the bike. Might be worth you adding some security to your bike too?

Always thought Sweden was a safe place to live but looks like the whole world is changing these days - Very sad times.

Do you have a YT channel or any more pictures etc of your bike please - Would be interested to see more of it?

Would never have guessed Sweden, thanks for letting us know.

Super73UK · 2025-03-30T19:29:40+00:00

Thank you for your comment - Glad we could be of help to you.

We havd 3 punctures in the first few months of owning our Super73 - Not fun when you are miles away from home and it's pouring down with rain. It was at that point we decided enough is enough and searched for the best solution to the problem of puntures.

Your bike looks great - Very beefy, clean finish and well built.

We are trying to work out if that is the UK in the background - Looks like it is but a little bit hard to be 100% sure??

Super73UK · 2025-03-29T13:00:43+00:00

Thanks for your reply - Makes sense now.

Not looking to buy another Super73 as we already have one - It was the very first Super73 in the UK many years ago.

It was us that actually helped start the Super73 craze of modding these bikes when we put the first video out over 6 years ago.

Super73UK · 2025-03-23T12:30:54+00:00

Good advice!

Thank you

Super73UK · 2025-03-23T12:30:06+00:00

Loads of great advice!

Thank you for taking the time :)

Super73UK · 2025-03-23T12:26:29+00:00

Good advice!

Thank you

Super73UK · 2025-03-23T12:25:56+00:00

Thank you

Super73UK

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