---
product_id: 197806
title: "Kryptonite LK41051 KryptoLok Series 2 Standard Heavy Duty Bicycle U Lock with 4ft Flex Bike Cable"
brand: "kryptonite"
price: "S$159"
currency: SGD
in_stock: true
reviews_count: 13
category: "Kryptonite"
url: https://www.desertcart.sg/products/197806-kryptonite-lk41051-kryptolok-series-2-standard-heavy-duty-bicycle-u
store_origin: SG
region: Singapore
---

# 13mm hardened steel shackle 4ft Kryptoflex double loop cable Anti-drill & disc-style cylinder Kryptonite LK41051 KryptoLok Series 2 Standard Heavy Duty Bicycle U Lock with 4ft Flex Bike Cable

**Brand:** kryptonite
**Price:** S$159
**Availability:** ✅ In Stock

## Summary

> 🔐 Lock in your peace of mind — because your bike deserves Kryptonite-level protection!

## Quick Answers

- **What is this?** Kryptonite LK41051 KryptoLok Series 2 Standard Heavy Duty Bicycle U Lock with 4ft Flex Bike Cable by kryptonite
- **How much does it cost?** S$159 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.sg](https://www.desertcart.sg/products/197806-kryptonite-lk41051-kryptolok-series-2-standard-heavy-duty-bicycle-u)

## Best For

- kryptonite enthusiasts

## Why This Product

- Trusted kryptonite brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Noise-Free Transport:** Anti-rattle bumpers keep your ride quiet and hassle-free
- • **Weatherproof Durability:** Rotating dustcover & vinyl coating protect against elements and rust
- • **Unmatched Cut Resistance:** 13mm MAX-PERFORMANCE steel shackle defies thieves’ tools
- • **Dual-Lock Security System:** U-lock plus 4ft Kryptoflex cable secures frame and wheels effortlessly
- • **Versatile Carrying Solution:** Transit Flexframe bracket offers sleek, customizable lock storage on the go

## Overview

The Kryptonite LK41051 KryptoLok Series 2 is a heavy-duty U-lock featuring a 13mm hardened steel shackle and a 4-foot Kryptoflex double loop cable for comprehensive bike security. Its reinforced crossbar design, anti-drill disc-style cylinder, and weather-resistant features like a rotating dustcover and vinyl coating ensure robust protection against theft and the elements. The included Transit Flexframe bracket offers convenient, noise-free transport, making it a top choice for serious cyclists seeking reliable, versatile security.

## Description

Replaced with new and improved design in 2017 - check out our New U lock, it will send any bike thief running!. 13mm hardened MAX-PERFORMANCE STEEL SHACKLE resists cutting and leverage attacks. Includes 4’ KRYPTOFLEX™ DOUBLE LOOP CABLE for securing front wheel or accessories. Reinforced HARDENED CROSS BAR DESIGN provides increased protection. HIGH SECURITY DISC-STYLE CYLINDER. Center keyway defends against leverage attacks. ANTI-RATTLE BUMPERS reduce noise during transport. Rotating dustcover protects cylinder. Includes NEW TRANSIT FLEXFRAME-U transportation system which allows for versatile carrying.Protective vinyl coating.2 STAINLESS STEEL KEYS. Key Safe Program.

Review: It does its job. - Despite seeing some harsh reviews for this lock, I’m giving it five stars for a couple of reasons. Firstly, it’s prevented my bike from being stolen so far, and I can’t ask for more than that. I mean, it is sort of the entire reason I purchased the lock in the first place. With that in mind, there would have to be some meaningful drawbacks for the lock to have less than five stars. For the sake of comparison, my previous bike lock was a cheap plastic-coated cable with a key lock. While the length and flexibility was nice, it seemed too thin and flimsy, and I was frequently told that bicycle thieves could cut it with ease. Additionally, the locking mechanism frequently malfunctioned, making it difficult to unlock it. By contrast, every part of the Kryptonite U-lock is thicker and more robust. It simply looks and feels far more secure than the previous lock. The locking mechanism itself is also far superior. There is a sliding cover to protect the keyhole from the elements, an excellent feature for rainy Corvallis, OR. I have yet to notice any malfunctions or sticking points when unlocking it. My one minor complaint is that the entire U-shaped portion of the lock completely separates from its base whenever I unlock it. I understand that this ultimately makes it easier to put the lock on more parts of my bike or cover larger distances, but I rarely actually need the lock to completely separate; it would be just fine if it functioned like a normal padlock, with one side of the U-shape pivoting when unlocked. However, this is a minor quibble, and I just have to make sure that I’m holding both parts of the lock before I turn the key all the way. Anyway, the inclusion of a couple useful accessories outweighs the small “separation” drawback. The sturdy steel cable can be used in conjunction with the U-lock, which is handy to secure both of your wheels if your bike is going to be left unattended for a long time. There is also a small device that attaches to your bike frame, allowing you to easily holster the U-lock when you’re bicycling. Overall, this Kryptonite U-lock has done its job, and that’s all I can ask for. My bike hasn’t been stolen, and the lock is a huge upgrade over my last one. Finally, although I could have knocked off a star over the annoying issue of the lock separating, there are two useful accessories that easily outweigh the slight inconvenience. 5/5 stars.
Review: Worked out well for my bike. Perhaps not so well for others. - The lock seems solid, and the cover over the keyhole should decrease the likelihood of rust. The 4' cable is the perfect length for securing the front wheel to the back when using the U lock to lock the back wheel (through the back triangle) to a rack. You can't do much more with it, but extra length would mean it would be harder to carry around. These two items sold together are a great team and a great value package. The only area of contention with this package is the much-discussed flex bracket. For me it has worked out perfectly, but I hated it at first. As others have mentioned, the bracket is quite large so it sits out a long way from the frame. In addition, the way the lock slides in and out of the bracket requires quite a lot of extra space. For these reasons, I couldn't place it in the central triangle of the bike as I normally would, for fear of bashing the frame when taking the lock in and out of the bracket. However, there is a fair amount of flexibility in the way your lock is pointing when sat in the bracket, which allows for a lot of experimentation in where to put it. I tried A LOT of different placements and most of them just didn't look good and/or caused the lock to rub on my legs when pedaling. I was just about to give up when I found a position which works well on my bike. I've had no problems with the bracket slipping at all, and am very happy with the purchase. For this reason I give it 5 stars, but I can imagine how others with different models of bike would not have similar luck, and would be very frustrated and disappointed. For information: I have a Trek 7.2fx, and the position I found was at the front end of the cross bar, in front of the break cable (just before it threads out of the tube). The bracket is mounted on the right side of the cross bar (bracket pointing horizontal), with the lock pointing diagonally back and down towards the pedals. Due to the triangular shape of the cross bar here, the bracket sits well against it and doesn't slip. And due to the shape and balance of the lock, the way it is angled is how it would naturally dangle if you balanced it on your hand. This means that the bracket is not trying to fight to keep the lock upright, and therefore adding to the stability. It's not where I would normally mount a lock, but I now like the way it looks, and it feels very stable. I also didn't need to trim the strap for it to fit here.

## Features

- Replaced with new and improved design in 2017 - check out our New U lock, it will send any bike thief running!
- 13mm hardened MAX-PERFORMANCE STEEL SHACKLE resists cutting and leverage attacks
- Includes 4’ KRYPTOFLEX DOUBLE LOOP CABLE for securing front wheel or accessories
- Reinforced HARDENED CROSS BAR DESIGN provides increased protection
- HIGH SECURITY DISC-STYLE CYLINDER
- Center keyway defends against leverage attacks
- ANTI-RATTLE BUMPERS reduce noise during transport
- Rotating dustcover protects cylinder
- Includes NEW TRANSIT FLEXFRAME-U transportation system which allows for versatile carrying
- Protective vinyl coating

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B005YPK8G2 |
| Additional Features | Anti-Drill |
| Best Sellers Rank | #4,313 in Sports & Outdoors ( See Top 100 in Sports & Outdoors ) #7 in Bike U-Locks |
| Brand | Kryptonite |
| Brand Name | Kryptonite |
| Color | Black |
| Control Method | App |
| Controller Type | Hand Control |
| Customer Reviews | 4.4 out of 5 stars 6,191 Reviews |
| Finish Types | Vinyl |
| Global Trade Identification Number | 00720018001072, 00720018999416 |
| Included Components | Kryptonite Kryptolok Series 2 Standard Bicycle U-Lock With Transit Flexframe Bracket (4-Inch X 9-Inch) With 4-Foot Flex Cable, Transit Flexframe Bracket |
| Item Dimensions | 9.02 x 4.02 x 1.18 inches |
| Item Weight | 1.5 pounds |
| Item dimensions L x W x H | 9.02 x 4.02 x 1.18 inches |
| Lock Type | U-lock |
| Manufacturer | Kryptonite |
| Manufacturer Part Number | 001072 |
| Material | hardened Performance steel shackle |
| Material Type | hardened Performance steel shackle |
| Model Name | Kryptolok Serie 2 Ls + Flex |
| Model Number | LK41051 |
| Number of Items | 1 |
| Number of Pieces | 2 |
| Recommended Uses For Product | Security |
| Shape | U Shape |
| Special Feature | Anti-Drill |
| Style Name | Original |
| UPC | 720018001072 |

## Product Details

- **Brand:** Kryptonite
- **Special Feature:** Anti-Drill
- **Lock Type:** U-lock
- **Item dimensions L x W x H:** 9.02 x 4.02 x 1.18 inches
- **Material:** hardened Performance steel shackle

## Images

![Kryptonite LK41051 KryptoLok Series 2 Standard Heavy Duty Bicycle U Lock with 4ft Flex Bike Cable - Image 1](https://m.media-amazon.com/images/I/519j2XSEy1L.jpg)
![Kryptonite LK41051 KryptoLok Series 2 Standard Heavy Duty Bicycle U Lock with 4ft Flex Bike Cable - Image 2](https://m.media-amazon.com/images/I/914w+uYyixL.jpg)

## Available Options

This product comes in different **Size, Style** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ It does its job.
*by M***W on February 13, 2018*

Despite seeing some harsh reviews for this lock, I’m giving it five stars for a couple of reasons. Firstly, it’s prevented my bike from being stolen so far, and I can’t ask for more than that. I mean, it is sort of the entire reason I purchased the lock in the first place. With that in mind, there would have to be some meaningful drawbacks for the lock to have less than five stars. For the sake of comparison, my previous bike lock was a cheap plastic-coated cable with a key lock. While the length and flexibility was nice, it seemed too thin and flimsy, and I was frequently told that bicycle thieves could cut it with ease. Additionally, the locking mechanism frequently malfunctioned, making it difficult to unlock it. By contrast, every part of the Kryptonite U-lock is thicker and more robust. It simply looks and feels far more secure than the previous lock. The locking mechanism itself is also far superior. There is a sliding cover to protect the keyhole from the elements, an excellent feature for rainy Corvallis, OR. I have yet to notice any malfunctions or sticking points when unlocking it. My one minor complaint is that the entire U-shaped portion of the lock completely separates from its base whenever I unlock it. I understand that this ultimately makes it easier to put the lock on more parts of my bike or cover larger distances, but I rarely actually need the lock to completely separate; it would be just fine if it functioned like a normal padlock, with one side of the U-shape pivoting when unlocked. However, this is a minor quibble, and I just have to make sure that I’m holding both parts of the lock before I turn the key all the way. Anyway, the inclusion of a couple useful accessories outweighs the small “separation” drawback. The sturdy steel cable can be used in conjunction with the U-lock, which is handy to secure both of your wheels if your bike is going to be left unattended for a long time. There is also a small device that attaches to your bike frame, allowing you to easily holster the U-lock when you’re bicycling. Overall, this Kryptonite U-lock has done its job, and that’s all I can ask for. My bike hasn’t been stolen, and the lock is a huge upgrade over my last one. Finally, although I could have knocked off a star over the annoying issue of the lock separating, there are two useful accessories that easily outweigh the slight inconvenience. 5/5 stars.

### ⭐⭐⭐⭐⭐ Worked out well for my bike. Perhaps not so well for others.
*by 1***1 on May 5, 2013*

The lock seems solid, and the cover over the keyhole should decrease the likelihood of rust. The 4' cable is the perfect length for securing the front wheel to the back when using the U lock to lock the back wheel (through the back triangle) to a rack. You can't do much more with it, but extra length would mean it would be harder to carry around. These two items sold together are a great team and a great value package. The only area of contention with this package is the much-discussed flex bracket. For me it has worked out perfectly, but I hated it at first. As others have mentioned, the bracket is quite large so it sits out a long way from the frame. In addition, the way the lock slides in and out of the bracket requires quite a lot of extra space. For these reasons, I couldn't place it in the central triangle of the bike as I normally would, for fear of bashing the frame when taking the lock in and out of the bracket. However, there is a fair amount of flexibility in the way your lock is pointing when sat in the bracket, which allows for a lot of experimentation in where to put it. I tried A LOT of different placements and most of them just didn't look good and/or caused the lock to rub on my legs when pedaling. I was just about to give up when I found a position which works well on my bike. I've had no problems with the bracket slipping at all, and am very happy with the purchase. For this reason I give it 5 stars, but I can imagine how others with different models of bike would not have similar luck, and would be very frustrated and disappointed. For information: I have a Trek 7.2fx, and the position I found was at the front end of the cross bar, in front of the break cable (just before it threads out of the tube). The bracket is mounted on the right side of the cross bar (bracket pointing horizontal), with the lock pointing diagonally back and down towards the pedals. Due to the triangular shape of the cross bar here, the bracket sits well against it and doesn't slip. And due to the shape and balance of the lock, the way it is angled is how it would naturally dangle if you balanced it on your hand. This means that the bracket is not trying to fight to keep the lock upright, and therefore adding to the stability. It's not where I would normally mount a lock, but I now like the way it looks, and it feels very stable. I also didn't need to trim the strap for it to fit here.

### ⭐⭐⭐⭐ Strong, Durable, Safe, but One More Inch of Width Would Have Been Nice
*by R***N on December 9, 2013*

Large enough to fit around the wheel and frame of my bike at any sort of bike-parking structure, and solid enough to make me feel safe leaving it in a high-traffic area in a big city. I've been using the lock for a about year while I commute every day, and I've never had a problem. My reason for 4 stars instead of 5 is that if I have to lock my bike to a sign post rather than a bike parking rack, this u-lock doesn't always reach my around my wheel and fender. If the sign post is a closed rectangle, I can lock my wheel down, too. If the post has a rectangular front but then flays outward in the back, that makes it a little too wide for the u-lock to fit around. I've ended up either looking for a different post or just locking my frame to the post, which works, but it would be nice not to have to do that all the time, especially since the lock is on the larger side. Another reason for 4 stars: the attachment piece that holds the lock to the bike isn't the easiest to set up or use. I haven't had success finding a suitable spot for it on my bike where it's out of the way of my long legs (and I'm 6'2" with a big bike frame to match) so I just carry it in my bike bag, which isn't a big deal, but since this is one of the features of the product, I would have liked it to work better. The cable is easy to use, flexible and strong, and helps me lock my bike to my girlfriend's bike so we don't have to bring two locks all the time. It also solves the problem I mentioned above of locking my bike to posts that are larger than usual, although I don't always devote the extra space in my bag to bringing the cable, so that use doesn't come in handy all that often. If you have a nice bike, or you are in a place where bike theft is common, you really don't want to mess around with a cheap bike lock. The cost of this lock is much less than the price of a new bike, or new wheel, or a car, so the investment of slightly more dollars for this lock up front makes sense.

## Frequently Bought Together

- Kryptonite KryptoLok Series 2 Standard Heavy Duty Bicycle U Lock with 4ft Flex Bike Cable
- Ascher Ultra Bright USB Rechargeable Bike Light Set, Powerful Bicycle Front Headlight and Back Taillight, 4 Light Modes, Easy to Install for Men Women Kids Road Mountain Cycling Black
- Kryptonite Keeper 785 Bike Chain Lock, 2.8 Feet Long Heavy Duty Anti-Theft Bicycle Chain Lock with Keys for Bike, Motorcycle, Scooter, Bicycle, Door, Gate, Fence

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.sg/products/197806-kryptonite-lk41051-kryptolok-series-2-standard-heavy-duty-bicycle-u](https://www.desertcart.sg/products/197806-kryptonite-lk41051-kryptolok-series-2-standard-heavy-duty-bicycle-u)

---

*Product available on Desertcart Singapore*
*Store origin: SG*
*Last updated: 2026-09-07*