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SON Wheel Diameter Measuring Tool – For Precise Hub Dynamo
SON Wheel Diameter Measuring Tool — the essential accessory for precise calibration of SON hub dynamos.
✔ Measures the exact internal rim diameter (not the nominal size)
✔ Required to set the correct wheel circumference in your SON dynamo-powered lighting system
✔ Made of durable metal — precise, reliable and long-lasting
✔ Used by professional bike builders and touring cyclists worldwide
✔ Compatible with all standard bike rims (26", 28", 700c, 650b)
Installing a SON hub dynamo? This tool ensures your speed and distance readings are accurate.
Free shipping from €89 and 30-day money-back guarantee. Order now!
Accuracy starts with the right measurement.
The SON Wheel Diameter Measuring Tool is a precision instrument designed to measure the exact internal diameter of your bike rim. This measurement is essential for correctly calibrating SON hub dynamos, which use the wheel’s true circumference to calculate and display speed and distance in compatible lighting systems (e.g. SON Edelux II with I-Light or Supernova M99).
Why is it necessary?
SON hub dynamos with integrated speed/distance functions require the exact wheel circumference to provide accurate data. Using the theoretical size (e.g. “700x28c”) leads to significant errors. This tool gives you the real measurement needed for perfect calibration.
Key Features:
- Precise measurement — determines the true internal rim diameter for accurate circumference calculation
- Durable metal construction — built to last, with high reliability
- Easy to use — simply insert into the rim and read the diameter
- Universal compatibility — works with 26", 28", 700c, 650b and most standard rims
- Official SON accessory — designed by Schmidt Original Nabendynamo, the maker of SON hubs
Technical Specifications:
- Brand: SON (Schmidt Original Nabendynamo)
- Model: Wheel Diameter Measuring Tool
- Material: Metal
- Purpose: Accurate rim diameter measurement for SON hub dynamo calibration
- Compatibility: All standard bicycle rims
- Weight: ~50 g
What’s included?
- SON Wheel Diameter Measuring Tool
- 24-month warranty
- Free shipping from €89 across Europe
Why buy from Mognetti Bike?
- Technical expertise — we specialize in premium dynamo lighting systems
- 2-year warranty handled directly by us
- WhatsApp support — message us for help with SON dynamo setup
- Secure payments — credit card, PayPal or pay in installments with Heylight
- 30-day money-back guarantee — free returns on all accessories
Limited stock! Order now and ensure perfect accuracy for your SON dynamo lighting system.
| Brand | Schmidt |
|---|
Fast & Reliable Shipping in Italy
Place your order by 12:00 PM (GMT +1), Monday to Friday, and we’ll dispatch it the same business day. In many cases, we can process orders placed later as well.
If your order is placed on a public holiday or includes changes or special requests, shipping will be postponed to the next working day.
We ship exclusively with trusted express couriers. Estimated delivery times:
- 24 business hours for most mainland destinations
- Up to 48 hours for islands or remote areas
A tracking code will be sent by email once the order has shipped. In some cases, tracking may activate within 24 hours after dispatch.
All items are carefully packaged to ensure safe and secure delivery.
Accepted Payment Methods
- Major credit and debit cards
- PayPal
- Bank transfer
- Installment payments via Heylight (available only in Italy)
Buy Now, Pay Later with Heylight
For customers in Italy, we offer the option to split your purchase into monthly payments with Heylight. Simply select this option at checkout and complete the financing request via the secure Heylight portal. Approval is usually received within minutes. Once confirmed, we’ll ship your order immediately.
Need Help?
Send us a WhatsApp message (text only – no calls)
Returns and Refunds
How to Request a Return
You can return your order within 30 days from the delivery date, with the exception of E-Bikes and bicycles, which are covered by the manufacturer's warranty.
Returning a product is quick and easy. Just follow these steps:
- Email us at shop@mognettibike.it including your personal details and order number.
- You’ll receive a confirmation email with your return number and further instructions.
- Write your order number clearly and follow the provided return instructions.
- Use the original packaging to prepare your return.
- If you can't print the return form, include a note in the box with the name and order number of the purchaser.
- Seal the package carefully.
- We’ll send you a confirmation email as soon as the return arrives at our warehouse.
Is the Return Free?
Returns are free of charge for most products. However, E-Bikes and bicycles are excluded and fall under the manufacturer's warranty. Shipping for these returns may be at the customer's expense.
When Will I Receive My Refund?
Once your return is approved, we will issue a refund using the same payment method you used for your order. Refunds are processed within 30 days of receiving your returned item at our facility.
Need Help?
If you have any questions or need assistance, please contact our support team. We’re here to help.
For full details, visit our Returns and Refunds page.
