Bicycle Crankset
Replacement Service
The crankset is the main part of your bike where the pedals attach. If the metal arm bends, the gear teeth wear down, or the pedal holes break, your bike will stop moving. Karachi Repairs brings a complete mobile bike repair service to your door. We take off the broken parts safely and install a brand new crankset so you can pedal smoothly and safely again.
Mobile Bicycle Part Replacement
Did one of your pedals fall out because the hole on the bike arm is stripped and ruined? Are the sharp teeth on your front gears worn down so much that the chain keeps slipping when you push hard? These problems cannot be fixed with a simple adjustment. When the metal is broken, worn, or stripped, you need to replace the entire crankset. Tell us your address and what kind of bike you have. Our friendly, experienced bike mechanics will come right to your home. We bring the right tools to take off the old, damaged parts without hurting your bike frame. We will install a brand new crankset so you can ride safely again without the chain jumping around.
REQUEST A REPAIR VISIT
Safe Tool Use:
Protecting Your Bike Frame
Replacing a crankset is one of the hardest jobs on a bicycle. The metal parts are pushed onto the bike frame very tightly so they do not fall off while you ride. If you watch someone who does not know what they are doing, they will take a heavy metal hammer and hit the bike as hard as they can to get the part off. This is a terrible idea. Hitting the bike breaks the delicate bearings hiding inside the frame. It also dents the metal tubes of the bicycle forever. We do things the safe, correct way. We bring a special tool called a 'crank puller.' This tool screws into the part and gently pushes it off the bike without a single hit from a hammer. When we put the new part on, we use safe grease and tighten the bolts perfectly so the new part stays on safely for years.
Using the Puller Tool: We never use a hammer on your bike. We carefully screw our metal pulling tool into the center of the broken part. As we slowly turn the handle on our tool with a wrench, the broken arm slides smoothly and safely off the bike frame, keeping all the delicate parts inside totally safe.
Cleaning the Area: When the old, broken part is finally off, the middle of the bike is usually covered in thick, black mud and rust. Before we put the brand new, clean part on, we scrub this area until the metal shines. We wipe away the dirt so the new parts spin smoothly without making any noise.
Tightening the Right Way: When we slide the new crankset onto the bike, we must make sure it is tight enough to hold your body weight. We do not just guess. We use a big, special wrench that clicks when the bolt is tight enough. This stops the bolt from breaking and keeps the pedals perfectly safe.
Square Taper, Hollowtech,
And Kids Bike Parts
Not all bicycle pedals and gears attach to the bike the same way. Older city bikes and kids' bikes use a simple system called a 'square taper'. This has a square piece of metal holding everything together. It is very strong but requires a lot of force and a special screw tool to remove. Modern mountain bikes and fast, expensive road bikes use completely different parts. They use hollow metal tubes that slide right through the bike frame to save weight. These new systems are very delicate. If you turn the wrong bolt on a modern bike, you will crack the soft aluminum instantly.
Our mechanics know exactly how to work on all these different types of parts. Whether you have a simple commuter bike that just needs a basic, heavy gear set replaced, or a brand new racing bike that needs the most careful, delicate wrenching, we have the skills to handle it. We bring all the different sizes of puller tools for every type of bike, so you do not have to worry about us using the wrong tool and damaging your bicycle. We keep it safe and effective.
Clear Pricing Before We Start
Honest Quotes
We ask you what kind of bike you have before we arrive. Fixing a simple single-gear bike costs less than replacing parts on an expensive mountain bike with many gears. We tell you the clear total price upfront for the brand new parts and the labor to install them. You do not get any surprise fees added when the work is finished.
Good Quality Parts
If we need to replace the metal arms on your bike, we only use strong, reliable parts. We do not use cheap, weak metal that will bend again the next time you ride over a bump. By using good quality, strong replacement parts, your bike will stay safe and last much longer, giving you a smooth, easy ride.
Friendly Bike Mechanics
Changing big metal parts properly takes experience and patience. If done poorly, the parts will be loose and break again quickly. Our mechanics are friendly and easy to talk to. They know how to tighten the parts safely and align everything so the chain moves perfectly, ensuring your bike rides smoothly when they leave.
We Bring The Bike Shop
Directly To Your Home
Taking a dirty, greasy bicycle with a broken pedal into busy traffic to find a repair shop is very annoying. Bikes with broken parts stick out and do not fit nicely into a small car. The heavy chain grease will leave thick, black stains everywhere on your nice seats. Once you finally find a shop, you usually have to leave the bike there and wait days just for a simple part change. We think fixing your bike should be much easier. Our mobile service makes fixing your bike very simple for you by bringing the whole repair shop to your door.
Our mechanic arrives at your house with a large bag full of heavy, special tools. We bring a stand to hold the bike safely up in the air. We carry the brand new parts, fresh grease, and cleaning rags. We remove the old broken parts and put the new ones on right in your garage, garden, or driveway. You can relax at home while we take care of all the hard, dirty work, getting your bike safe to ride again on the exact same day.
Why Choose Us For Your Part Replacement
Big metal parts need to be removed and installed perfectly to keep you safe. A bad repair will leave you with a pedal that falls off while riding. Here is why our service is the safest choice.
Safe Extraction Tools
We do not use a hammer to knock parts off your bike. Hitting the bike breaks the metal frame forever. We use a special tool that smoothly pushes the broken parts away from the bike, keeping the frame perfectly safe from damage.
Correct Tightness
If the new parts are not tight enough, they will rattle loose. If they are too tight, the metal will crack. We use a special large wrench that clicks when the bolt is tight enough, so your bike is perfectly strong and safe to ride.
Cleaning Before Installing
When we take the old parts off, there is always dark, thick mud left behind. We scrub the middle of the bike completely clean before putting the new parts on. This stops old dirt from ruining your shiny new gear set.
Matching the Chain
When you get a new set of front gears, the old chain might not fit the new teeth properly. We always check to make sure the old chain works. If it does not fit, we can replace the chain too so everything runs perfectly smooth.
Save Your Time
You do not need to drop your bike off at a shop and wait for a week just for a part swap. We come to your house, change the heavy parts right on the spot, and let you get back to riding your bike that very same day.
Clear Prices
Once our mechanic looks at the bike to see what is broken, we tell you exactly how much it will cost for the new parts and labor. You agree to the price before we start working. There are no sudden extra charges.
Why Do Cranksets Break?
Heavy metal parts do not break for no reason. Understanding why your part failed helps us fix it properly and stop it from happening again.
Stripped Pedal Holes
If you ride your bike with a loose pedal, the pedal shakes. This shaking ruins the soft metal hole it sits inside. Very quickly, the hole gets bigger and the metal threads are ripped out entirely. The pedal falls off and will not screw back in.
The Fix: The metal arm is ruined. We remove it and put on a brand new crankset part.
Worn Out Gear Teeth
If you ride a lot with a very dirty, sandy chain, the dirt acts like a file. It grinds down the big metal teeth on the front gears. The teeth get very sharp and small. When this happens, the chain skips right over the gears when you push hard.
The Fix: We take off the sharp, old gear ring and put a new set of gears on.
Loose, Wobbling Arms
If you can wiggle the long pedal arm from side to side, the square hole holding the arm to the bike is ruined. Riding with a loose bolt slowly rounds out the square hole inside the arm, making it useless.
The Fix: We remove the wobbly, ruined arm and put on a fresh, perfectly fitting part.
Bent Crank Arms
If you crash your bike or jump off something very high, the heavy hit can actually bend the thick metal arm holding the pedal. A bent arm feels very strange when you pedal and will scrape against the painted bike frame.
The Fix: We take off the bent, unsafe part and put a brand new, straight arm on the bike.
Wrong Pedal Forced In
The left pedal screws in backward. If someone tries to force the left pedal in using the normal direction with a big tool, it cuts new, bad metal threads into the hole. The pedal will stick halfway out and eventually fall off.
The Fix: We have to replace the ruined metal arm with a new one that has clean threads.
Hammer Damage
If someone tried to take the parts off your bike before by hitting them with a hammer instead of using the right puller tool, they probably bent the gears or dented the soft aluminum heavily. The parts are ruined.
The Fix: We take off the damaged pieces safely with our tools and put clean new parts on.
How To Book Our Mobile Repair Service
Fixing your bike is easy with our mobile service. Here are the simple steps our mechanics follow when they come to your house.
From Broken Parts To Smooth Riding
You Tell Us The Problem
Tell us if the pedal fell off or the chain is slipping. Sending a quick photo of the broken part on WhatsApp helps us know exactly what new parts and special tools to bring to your house.
We Check The Bike
Our mechanic arrives and puts your bike safely on a stand. We check the broken metal arm and make sure nothing else was damaged when the pedal broke or the bike fell over.
We Give A Clear Price
We explain what needs to be done. We tell you the cost for the new metal parts and the labor to install them safely. You get a clear, final price, and we do not start working until you say yes.
Removing the Broken Part
We use our special puller tools to gently take off the old, ruined metal pieces without hitting the bike frame with a hammer. We clean all the old mud out of the area.
Installing and Testing
We put the fresh, strong parts on the bike. We use our big wrenches to make sure the bolts are tight enough so they will not loosen again. We put the pedals on and test the gears so everything runs smooth.
Warning Signs You Need Help Now
What To Do Before We Arrive
Ready to Fix Your Bike? Call Karachi Repairs.
Since 2015, we have safely removed and replaced thousands of broken bicycle parts for riders across the city. We know exactly how to use the special puller tools, tighten the big bolts so they do not rattle loose, and align everything perfectly straight. A strong, fresh crankset means you can ride up big hills safely, push the pedals hard without the chain skipping, and completely stop worrying about your pedal falling off in the middle of a busy street.
Call or WhatsApp 0332-6678611, or fill out the form on this page to ask for a mobile mechanic visit. Tell us your location and describe what part of your bike is broken. We will send a fully prepared bike mechanic directly to your house, bringing brand new metal parts, the right big wrenches, and safe tools to fix your bike quickly and properly right in your driveway.
Parts Fixed Safely, Not Just Hammered Poorly
Do not ignore a bike that feels loose when you pedal or a chain that jumps over the teeth. A small wobble today turns into a completely ruined, expensive metal frame tomorrow when you let the loose parts scrape against the bike. Trying to force a stuck part off the bike yourself using a big hammer will bend the delicate gears and crack the frame entirely. If you keep riding with stripped threads, your pedal will fall out while you are going fast, causing a terrible crash. The true value of a professional part replacement service is making sure the heavy parts are removed safely without hitting the bike. We do not just use a hammer and leave. We use special pulling tools to take the broken metal off smoothly, clean the area perfectly, install fresh, strong parts, and use large wrenches to make sure the bolts are tight enough so the bike is permanently safe.
As a specialized part of Karachi Repairs, we know exactly how to handle all kinds of bicycle repairs. From taking big, heavy square arms off old city bikes to carefully replacing expensive hollow metal parts on fast road bikes, we do it all safely without breaking your frame. We save you the big headache of trying to cram a broken, greasy bicycle into your car. Instead, we bring our friendly service and proper tools directly to your house. Every job is done with care, priced fairly, and finished safely right in front of you.
If you hear a loud grinding sound when you pedal, if your chain is slipping over the teeth, or if your pedal fell out, the easiest thing to do is send a quick WhatsApp message. Tell us what kind of bike you have, send a picture of the broken part, and we will send a helpful mechanic to fix it for you perfectly.
Explore More Bicycle Services Here
Part Replacement FAQs
The stripped pedals, slipping chains, and broken metal questions our Karachi clients ask most often.
Why did my pedal fall off the bike?
A loose pedal ruins the metal hole it sits inside. The threads get ripped out entirely. We have to replace the whole metal arm so you have a safe place to put your foot.
Why does my chain slip when I pedal hard?
Dirty chains grind down the metal teeth on the front gears. The teeth get very sharp and small and will not hold the chain. We take off the sharp ring and put a new set of gears on.
Do I need to bring my broken bike to your shop?
No, you do not have to leave your house. Our repair service is fully mobile. We bring the special tools, new parts, and a bike stand directly to your home and fix it safely there.
Why can I wiggle the whole pedal arm side to side?
Riding with a loose bolt slowly rounds out the square hole holding the arm to the bike, making it useless. We remove the wobbly, ruined arm and put on a fresh, perfectly fitting part.
Can I use a hammer to knock the broken part off?
No! Hitting the bike with a hammer breaks the delicate bearings hiding inside the frame. We use a special tool called a crank puller that gently pushes the broken part off safely.
Why did my left pedal go in crooked?
The left pedal screws in backward. If you force it in normally, it cuts new, bad metal threads and ruins the part. We replace the ruined metal arm with a new one that has clean threads.
How long does it take to change the parts?
Usually, it takes our mechanic about 45 minutes to safely use the special puller tools, clean the heavy mud away, and install the new parts perfectly tight.
What if the metal arm is bent and scraping my bike?
Stop riding immediately. If you keep pedaling, the bent metal will carve a deep hole into your painted bike frame forever. Call us, and we will safely put on a new, straight arm.
Will you tell me the price before you start?
Always. We look at the bike, see what parts are ruined, and give you a clear total price for the new parts and labor. We do not start working until you agree. No hidden charges.
Which areas of Karachi do you cover?
We provide our mobile bicycle repair service in all major areas, including DHA, Clifton, Gulshan-e-Iqbal, PECHS, North Nazimabad, Malir, and Bahria Town.
Areas We Cover
Across Karachi
Our mobile bike mechanics carry heavy-duty repair stands, special puller tools, and shiny new bike parts directly to your location across all major city zones.