2Bros Parts

CARBURETTOR REPAIR KIT VACUUM DIAPHRAGM MIKUNI CV BST40 1998-2007 KTM 640 LC4

$48.67

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Delivery to United States 5–8 business days

Spread the cost with Klarna

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The Mikuni CV BST40 Carburettor Repair Kit is a high-quality replacement set designed to restore functionality to the carburettor system. Engineered for durability and precision, the kit includes essential components for proper fuel delivery and throttle operation. Features include unmatched reliability and performance from high-tech materials, manufactured to exacting standards, and meets or exceeds OEM quality. This is a direct OEM replacement. Please see image before ordering. Easy to install, but professional installation is recommended if unsure. Kit Includes: Diaphragm for throttle valve, needle valve 2.8mm, gasket set BST40-225, idling jet. Cross-Reference OEM Part Numbers: 58431028000, 58431020000, 58431099000, 58431007047, 58431007045. This kit is compatible with Mikuni CV BST40 carburetors.

Specifications
SKU
27-4701.AAA
Brand
No Brand
Availability
In Stock (3)
General Product Group
Carburettor & Intake
General Product Type
Carburetor Diaphragm
Variant Id
310579
Delivery5–8 business days
14-Day ReturnsHassle-free
Easy CheckoutCard friendly
Product details

FULL DESCRIPTION

Mikuni CV BST40 Carburettor Repair Kit for KTM 640 LC4

Restore your motorcycle's carburettor to peak performance with this high-quality Mikuni CV BST40 Carburettor Repair Kit. Designed as a direct OEM replacement, this kit provides the essential components needed to ensure proper fuel delivery and throttle response, allowing your engine to operate with renewed confidence and reliability.

Key Features:

  • Unmatched reliability and performance from high-tech materials
  • Manufactured to exacting standards for confident engine rebuilding
  • Meets or exceeds OEM quality specifications
  • Direct OEM replacement part
  • Offers the best value for money
  • Designed for straightforward installation, though professional assistance is recommended if unsure

Included Components:

  • Diaphragm for throttle valve
  • Needle valve 2.8mm
  • Gasket set BST40-225
  • Idling jet

Cross-Reference OEM Part Numbers:

  • 58431028000 (Diaphragm for Throttle Valve)
  • 58431020000 (Needle Valve 2.8mm)
  • 58431099000 (Gasket Set Mikuni BST40-225)
  • 58431007047 (Idling Jet)
  • 58431007045 (Idling Jet)
Before you buy

QUESTIONS? JUST ASK

Talk to John or Phil. Real people, Monday to Friday, 10:00 to 17:00 (UK time).

Call or email us with your make, model and year and we will check it for you before you order.

Yes. We ship from the UK. Orders ship within 3 working days, then delivery to the United States takes 5–8 business days. The delivery price is shown at checkout before you pay. Delivery details

Yes. You have 14 days from delivery to return it, unused and in its original packaging. Contact us first and we will send you the return instructions. Returns policy

By card, PayPal, Apple Pay or Google Pay, or spread the cost with Klarna. Payment is taken securely by Stripe, and the options for your order are shown at checkout.

Any customs duties or import taxes charged in the United States are paid by you when the parcel arrives. Any tax we collect ourselves is shown at checkout before you pay.

More answers in our FAQ.

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