Joyor S10-S-Z · Brakes

Brake lever feels soft or goes to the bar

A spongy lever on hydraulic brakes usually means air in the line or worn pads. This is a safety fix.

Difficulty: HardTime: 45–90 minutes7 things you need

Is this your problem?

  • Lever pulls much further than before
  • Lever feels spongy, or firmer after pumping it a few times
  • Brake grips weakly

Likely causes

1
Worn padsHow to tell: The lever travels further but still feels firm at the end. Check pads first: much easier.
2
Air in the hydraulic lineHow to tell: Spongy feel, gets firmer when you pump the lever.
3
Fluid leakHow to tell: Oily wet spots on the caliper, hose joints or lever. Oil on the disc too.
Check this first

Look at the pads (see the worn-pads guide). Look for any wet or oily spot on the brake parts.

What you need

Tools

Example photo: Torx driversExample photo
Torx drivers

A Torx set (T10–T30 covers most scooters). Brake disc bolts are often Torx; check the head shape before you buy.

Photo: JaredMcKenzie, CC0, resized
Example photo: Hex (Allen) keys, metricExample photo
Hex (Allen) keys, metric

A metric set, roughly 2 mm to 8 mm. Long-arm keys reach the recessed bolts on the stem and deck.

Photo: Leon Brooks, Public domain, resized
Example photo: Nitrile glovesExample photo
Nitrile gloves

Keep skin oil off the brake parts, and brake fluid off your skin.

Photo: unknown, Public domain, resized
Example photo: Clean lint-free clothExample photo
Clean lint-free cloth

A clean microfibre cloth or paper towel. Never one that has had oil or polish on it for brake work.

Photo: Polyesterchen, Public domain, resized
Example photo: Isopropyl alcoholExample photo
Isopropyl alcohol

90% or stronger. Cleans oil off brake discs and dries without leaving anything behind. Not the same as rubbing alcohol with added oils.

Photo: João Carlos Ávila, CC BY-SA 4.0, resized

Parts

Example photo: The right brake fluidExample photo
The right brake fluid

Only the type written on your brake (lever reservoir cap or caliper): DOT fluid or mineral oil. The two never mix; the wrong one ruins the seals. The photo shows a DOT fluid as an example.

Photo: Just a Man, CC BY 4.0, resized
Example photo: Brake pads for your caliperExample photo
Brake pads for your caliper

Pads are shaped to the caliper. Order ones listed for the Joyor S10-S-Z, or take an old pad to a shop to match the shape.

Photo: PetarM, CC BY-SA 3.0, resized

Photos show the kind of tool or part, not a specific product. We don’t sell anything and get nothing from any shop.

Step by step

Tap a step when it’s done to keep your place.

  1. Check the pads first

    Worn pads make the lever travel further. If they are thin, replace them and test again before doing anything else.

  2. Look for leaks

    Wipe the caliper, hose joints and lever clean with a dry cloth, squeeze the lever hard a few times and look again. Any fresh wet oil means a leak: that is a shop job.

  3. Find out which fluid your brake uses

    It is written on the lever reservoir cap or on the caliper: DOT (a number like DOT 4) or mineral oil. Joyor does not publish this for the S10-S-Z, so read it off your brake.

    DOT fluid and mineral oil must never be mixed. The wrong one destroys the seals.

  4. Bleed the brake, or have it bled

    Bleeding pushes fresh fluid through to drive the air out. It needs a bleed kit made for your brake’s fluid and fittings. If you have never done it, this is the time to let a shop do it: it is cheap, quick for them, and your stopping depends on it.

  5. Test standing still, then slowly

    The lever should feel firm and stop at the same point every time. Then test at walking speed.

Stay safe

  • Do not ride with a lever that reaches the handlebar.
  • Brake fluid (DOT) damages paint and skin. Wear gloves, wipe spills immediately.
  • Never get fluid or grease on the pads or disc. Oily pads have to be replaced.

When to take it to a shop

Any leak, any doubt about the fluid type, and bleeding if you have not done it before.

Also check

Written for the Joyor S10-S-Z using the maker’s published specs and error list (Joyor technical guide) plus general repair practice for scooters built this way. Parts and fittings can change between production batches: if yours looks different, trust your scooter and its manual. Repairs are at your own risk.

Found a mistake? Tell us.