SpeedBox 1.4 for Bosch SX (Smart System + Rim Magnet)
- For Bosch Performance Line SX motors Gen 4
- Unlock unlimited maximum speed
- Simple activation process
The SpeedBox 1.4 for Bosch SX (Smart System + Rim Magnet) removes the factory speed restriction from Bosch Performance Line SX Gen4 motors, unlocking your e-bike’s full potential. Designed specifically for models with the Bosch Rim Magnet setup, it offers precise integration and seamless operation. This tuning chip is engineered for reliability, maintaining natural motor behaviour and accurate data display when set up correctly.
Key Features and Benefits:
- Engineered for Bosch Performance Line SX Gen4 motors: Designed to work flawlessly with BDU3142 and BDU3143 drive units, ensuring a perfect electrical and software match for safe and consistent performance.
- Rim Magnet compatibility: Built for e-bikes using the Bosch Rim Magnet system, allowing easy installation without the need for additional adapters or rewiring, ensuring a clean and secure fit.
- Removes factory speed limiter: Overrides the default 25 km/h restriction, giving the rider access to the motor’s full capability for faster commuting or sportier riding when used off-road.
- Smart System integration: Works with Bosch Smart System firmware, ensuring stability during updates and full compatibility with the latest software revisions.
- Simple activation process: After installation, the tuning is activated through the e-bike’s menu by adjusting wheel circumference settings, allowing users to enable or disable the tuning when needed.
- Robust, reliable construction: Built from quality electronic components that resist vibration and temperature changes, ensuring long-term durability and consistent operation in all riding conditions.
The SpeedBox 1.4 provides precise and reliable tuning for Bosch SX systems without disrupting the natural pedal feel or drivetrain performance. Its compatibility with rim magnet setups makes it an ideal choice for riders seeking clean installation and consistent results. By safely unlocking the motor’s top-end speed, it gives experienced users the flexibility to optimise performance based on terrain and conditions.
SpeedBox 1.4 for Bosch SX offers an easy and reliable way to unlock more from your e-bike. Designed for performance and built for precision, it’s a dependable upgrade that enhances the capability of every Bosch Smart System motor.
Designed For:
- Performance Line SX motors of 4. Gen
- (Motor Models BDU3142)
- (Motor Models BDU3143)
- Mounted with 2 top screws
- E-bikes that have a magnet attached to a valve (Bosch Rim Magnet)
Not compatible with:
- Standard magnet
- ABS system
| Brand | SpeedBox |
| MPN | SB14-B |
Our Payment Options
Online we currently accept payment from the methods listed above including a wide range of finance options. In store we also accept payment in the form of cash and gift vouchers.
Finance Options
In order to get the kit you want, when you need it, we offer a highly flexible range of finance options to help you get the best products on your bike now rather than at the end of the season when you've saved up the cash to make the purchase. There are even interest free options which effectively spread the cost without costing you any extra.
D.T.(Automotives) Limited T/A Tweeks Cycles is authorised and regulated by the Financial Conduct Authority and is the broker and not the lender. Our FCA registration number is 689896. D.T.(Automotives) Limited offers credit products from Secure Trust Bank PLC trading as V12 Retail Finance, Klarna and Clearpay. Credit is provided subject to affordability, age and status. Minimum spend applies. Not all products offered by Secure Trust Bank PLC are regulated by the Financial Conduct Authority. Klarna is unregulated credit. Clearpay is unregulated credit, use responsibly, T&Cs & late fees apply.
Our Finance Providers
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D.T.(Automotives)Limited trading as Tweeks Cycles offer interest free and interest-bearing credit on purchases £300 and over which is provided by V12 Retail Finance.
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We also offer Klarna, pay now, pay in 30 days or pay in 3 equal instalments.
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We also offer Clearpay pay in 4 instalments.
UK Mainland Delivery Prices
| Delivery Type | Cost | Estimated Delivery Time |
| Standard Delivery for orders under £49.99 | from £1.33 | 2-3 working days from day of despatch(Excludes weekends and Bank Holidays) |
| Standard Delivery for orders over £49.99 | Free | |
| Bike Delivery | Free | 3-5 working days from day of despatch *(Excludes weekends and Bank Holidays) |
| Express Delivery | from £1.68 | 1-2 working days from day of despatch(Excludes weekends and Bank Holidays) |
| Special Delivery | from £12.54 | For any next working day delivery order before 4.30pm Monday to Thursday. For any weekend delivery order before 4.30pm Friday |
* Bike Delivery Info
A bike has to go though a Pre Delivery Inspection (PDI Check) prior to despatch, ensuring the bike is thoroughly checked and set up prior to you receiving. This also means an express delivery service is unavailable. We strive to despatch bikes within 3-5 working days. Please note this may change over school holidays and the festive season (November/December). For more information on the process please visit our pre-build page.
For international shipping please visit our delivery page.
For information about returning an item please visit our returns page.