Engineering shop request

[Gresini]

Hi anyone can intro a shop to trim rear brake disc down by 0.5-0.8mm?

JB lobang welcome too

 

[Khreis830]

you generally shouldn’t machine (trim) a brake disc that much, especially on a rear rotor.

[Gresini]

Advice accepted. Still waiting avail shops, SG / JB only thx.

[adesmond2]

On 4/12/2026 at 10:36 AM, Gresini said:

Hi anyone can intro a shop to trim rear brake disc down by 0.5-0.8mm?

JB lobang welcome too

 

Brakes are literally the only thing stopping you from kissing the back of a SBS bus. Trimming, skimming, or machining down a motorcycle brake disc (rotor) is a massive safety hazard.

If someone is asking for advice on doing this, here is the straight, hard truth you must tell them:

1. The Minimum Thickness Limit (The "Do Not Cross" Line)

Every single brake disc in the world has a "Minimum Thickness" (usually stamped right on the metal, looking like "MIN TH 4.5mm"). Motorcycle discs are already incredibly thin compared to car discs. A typical rear disc might start at 5.0mm thick. If you trim off 0.5mm to 0.8mm, you are almost certainly pushing it past the absolute minimum safe limit immediately.

2. The "Keropok" Effect (Warping and Snapping)

Why is the minimum thickness so important? Heat, bro. When you brake, the friction generates insane amounts of heat. The metal needs to be thick enough to absorb and dissipate that heat. If you thin the disc down:

It will warp instantly: The next time they brake hard downhill, the thin metal will overheat and warp like a potato chip. Then the brakes will pulse, grab, and feel terrible.

It can shatter: If it gets too thin and too hot, the structural integrity is gone. The disc can literally crack or shatter into pieces while riding. If the rear wheel locks up because the disc shattered into the caliper... game over.

3. The Caliper Piston Danger

Brake calipers are designed to work within a specific disc thickness range. If the disc is too thin, the pistons inside the caliper have to push out much further to make the pads touch the disc. If the disc is artificially thinned down too much, the pistons can actually push out past their seals. Brake fluid leaks everywhere, you lose all brake pressure instantly, and you have zero rear brakes.

Why is this person even asking to do this?

Usually, people only ask to skim a disc for two reasons. You need to tell them the proper fix for both:

Reason A: The disc is warped or deeply grooved.

The Beng Fix: "Just skim it flat again!"

The Real Fix: Buy a new disc! Motorcycle discs are surface-hardened. If it's warped or deeply grooved, it's already ruined. Skimming it just makes a ruined disc dangerously thin.

Reason B: They are trying to fit an aftermarket wheel or caliper and the spacing is tight.

The Beng Fix: "Just shave the disc a bit so it fits!"

The Real Fix: Fix the spacing! Use proper wheel spacers, shim the caliper mount, or get the correct parts. Never compromise the braking surface to fix a clearance issue.

The Final Verdict to give them

Bro, tell your friend: "A brand new OEM or good aftermarket rear brake disc costs maybe 100to100to200. Is your life, your bike, and your hospital bill worth saving $150?"

Car discs are thick and can sometimes be skimmed once. Motorcycle discs? Never. Tell them to throw the idea away, spend the money, and buy a new rotor. Safety first, bro, always!

 

Now, if you still want to do it. below is the locations (do at your own risk)

 

West Area (Jurong/Corporation):

Next Gen Performance (NGP)

: Specialized in brakes; located at REVV (1 Corporation Dr). Known for precision skimming.

KGC Workshop

: Offers rotor skimming services at 1 Corporation Dr.East Area (Ubi/Kaki Bukit):

RS Automotive

: Located at Ubi Road 1. Typical pricing for skimming is S$40 – S$80 per pair.

Chip Soon Auto

: Professional skimming service at Tampines/Ubi area.North Area (Woodlands):

One Zone Automotive

: Has a branch at Yishun Industrial St 1.

SK Garage Motorsports

: Located at Soon Lee Street; specializes in fixing brake judder via skimming. 

 

 

 

 

Johor Bahru (Cost Savings)

Prices in JB are significantly lower, usually ranging from RM80 to RM150 per pair. 

 

CS Disc Brake Supply & Services-Official

 

Repair service

OpenSkudai, Johor, Malaysia

Highly rated specialist. Pricing is roughly RM80 for a pair, often including a spray finish.

Unique Automotive Brake Shop

 

Auto parts store

OpenJohor Bahru, Johor, Malaysia

Specialist in brake upgrades and custom rotor work near Taman Sri Putra.

One Zone Auto Service Sdn. Bhd.

 

Car repair and maintenance service

OpenGelang Patah, Johor, Malaysia

Offers fully automated rotor skimming near the Second Link.

N Three Tyre & Service Centre

 

Car repair and maintenance service

OpenJohor Bahru, Johor, Malaysia

Quoted roughly RM150 for a pair of larger performance discs. 

 

Key Tips Before You Go

Check Thickness First: Most passenger car discs have a total wear limit of only 2mm(e.g., 22mm new, 20mm discard). If you remove 0.8mm and your discs are already worn, they may become too thin and prone to cracking.

New Pads: It is highly recommended to install new brake pads after skimming. Old, uneven pads will quickly score your newly smooth surface. 

 

 

 

[Gresini]

On 4/17/2026 at 12:21 PM, adesmond2 said:

Repair serv

Hi boss, car brakes skim not same bike.

In fact I looking for engineering shop to skim whole disk.

My rear disk used once a year only, at inspection centre.

[adesmond2]

On 4/19/2026 at 3:12 AM, Gresini said:

Hi boss, car brakes skim not same bike.

In fact I looking for engineering shop to skim whole disk.

My rear disk used once a year only, at inspection centre.

this is more towards design already, I had the same thoughts as yours, design it.. but honestly, not practical. ended up, forget it. Otherwise, if you really want, I think only the Malaysia ah boy bike shop that stretch of workshops might be willing to help you.

[Gresini]

Appreciate all comments, actually i looking for direct solutions only.

[Gresini]

[adesmond2]

Nice! so you manage to "trim it down"? in Singapore? the price and shop if you dun mind sharing? so that people can cross reference next time.

[Gresini]

3 hours ago, adesmond2 said:

Nice! so you manage to "trim it down"? in Singapore? the price and shop if you dun mind sharing? so that people can cross reference next time.

I ask friend help, he didn't tell me where who how much.... So sorry