MMX 4-Pinned crank hub | BMW S55 | N55

Engine failures caused by the standard three-piece crank hub on the S55 and N55 engine are (unfortunately) well known, but these are fully addressed with the installation of the MMR Performance 4-pinned single-piece crank hub. Together with the option of adding our Capture Plate for ultimate security. The OE crank hub unit's friction plate are known to slip rotationally, causing the timing to alter enough that piston-to-valve contact can occur, leaving owners with a very expensive repair bill. Our 4-pin version of our single-piece crank hub kit is simply the ultimate solution to preventing this problem before it happens on high horsepower engines.

The centrepiece of the MMR kit is the UK made CNC-machined one-piece crank hub, created from billet EN36 steel that's heat-treated with a 0.75mm case hardening, making it incredibly strong and durable. Included are four aerospace precision machined dowels that mechanically lock the hub to end of the crank itself, plus a brand new OE bolt. Installation of these dowels is certainly not a DIY job. But, to make the job easier for the professionals, ensuring that the required crank modifications are made safely and accurately, the MMR kit also includes a full installation jig that includes a bolt-on drilling guide, a location bolt for this guide, plus an HSS rolled high-speed drill bit. Together, the single-piece design combined with the four-pin location ensures that there is simply no way that the friction plates can ever slip. With the new OE crank bolt tightened appropriately, this delivers a transformational improvement in reliability and peace of mind versus the OE version.

Vehicle fitment

• Series: 1-Series, 2-Series, 3-Series & 4-Series
• Chassis code: F2x, F3x, F80, F82 & F87
• Engine code: N55 & S55
• Model variant: M135i, M235i, 335i, 435i, OG M2, M2C, M3 & M4
• Model year: 2011 - 2021

Package dimensions

19 × 17 × 8.5 cm (L × W × H)

📦 Regal Autosport Shipping Policy

Shipping Destinations

We proudly ship our products across the UK, Europe, the USA, Australia, South East Asia, and other locations globally.There are no regions we restrict shipping to.

Carriers and Delivery Times

• United Kingdom: Royal Mail for small items; DPD Local for parcels up to 30kg.
  Delivery estimate: 1–2 business days.
  

• International:
  

• Small packages: Royal Mail (postal service)
  

• Small/medium/large parcels: DHL Express.
  Delivery estimate: 2–15 business days, depending on destination.
  

Please note: We do not ship on weekends or UK Bank Holidays. Orders placed after 2 PM will be processed the following business day.

Order Processing

Orders placed before 2 PM are typically processed and dispatched the same day.
Orders placed after 2 PM will be processed on the next business day.

Shipping Costs

Shipping costs are calculated automatically at checkout based on the volumetric weight of your order.
We do not offer free shipping — instead, we focus on keeping product prices as competitive as possible.

Tracking

All orders are shipped via tracked and signed-for services.
Tracking information will be provided and can be accessed via:

• Your Regal Autosport account page in Shopify
  

• The respective courier’s website
  

Customs, Duties, and Taxes

• UK Customers: Prices include UK VAT.
  

• International Customers:
  

• UK VAT will be deducted at checkout.
  

• Customers are responsible for all customs duties, import taxes, and fees applicable in their country.
  

• Delivery times may be delayed by customs clearance — time is not of the essence for deliveries.
  

Lost or Damaged Items

In the rare case of lost shipments:

• If the courier confirms the parcel as lost, we will re-ship your order as quickly as possible.
  

For damaged shipments:

• Customers must assist us in submitting a claim with the courier.
  

• After confirmation, we will replace the item or offer a discount, depending on the situation.
  

We take great care in packaging, but please inspect your order upon arrival and contact us immediately if the item is damaged or missing.

Backorders

Orders containing backordered items will be dispatched once all items are available.
We do not split ship orders. If you require partial delivery, please place separate orders for in-stock and backordered items.

Local Pickup and Delivery

We do not offer local pickup or local delivery for online orders due to security verification policies.
However, customers are welcome to visit our store and pay via chip and PIN.

📦 Regal Autosport Shipping FAQs

Where do you ship to?

We ship across the UK, Europe, the USA, Australia, South East Asia, and worldwide.
 There are no regions we restrict shipping to.

Which carriers do you use?

• UK orders: Royal Mail (small items), DPD Local (parcels up to 30kg)
  
  

• International orders: Royal Mail (small packages) or DHL Express (larger parcels)
  
  

How long will my order take to arrive?

• UK deliveries: Typically 1–2 business days after dispatch.
  

• International deliveries: Usually 2–15 business days, depending on location.
  

Please note: We do not ship on weekends or UK Bank Holidays.

When will my order be dispatched?

Orders placed before 2 PM are usually dispatched the same business day.
 Orders placed after 2 PM are processed on the next working day.

How much does shipping cost?

Shipping costs are calculated at checkout based on the volumetric weight of your items.
 We do not offer free shipping — instead, we keep our product prices as competitive as possible.

Will I receive tracking information?

Yes!
All shipments are tracked and signed for. You’ll receive tracking information by email and can also track your order via:

• Your Regal Autosport account page
  

• The courier’s own website
  

Do I have to pay customs charges or import taxes?

• UK Customers: Prices include UK VAT.
  

• International Customers:
  

• We deduct UK VAT at checkout.
  

• You are responsible for any local customs duties, import taxes, or fees.
  

Delivery times may be affected by customs clearance, and time is not of the essence for international deliveries.

What happens if my order is lost or damaged?

• If your shipment is lost, we will re-ship your order once the courier confirms the loss.
  

• If your order is damaged, we will work with you to file a courier claim and either replace the item or offer a discount based on the situation.
  

Please inspect your delivery upon arrival and contact us immediately if there are any issues.

What if my item is on backorder?

Orders containing backordered items will be held until all items are available.
We do not split ship orders. If you require partial delivery, please place separate orders for in-stock and backordered items.

Can I collect my order in person?

We do not offer local pickup or local delivery for online orders due to security verification.
However, you are welcome to visit our store and pay via chip and PIN if you wish to purchase in person.