Bergfelt Racing Enterprises, LLC
4412 W. 6th Avenue
West Mayfield Boro
Beaver Falls, PA   15010-1915
(724) 462-7440

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Installed Needle and Seat

Mikuni Diaphragm Kart Carburetor Inlet Needle & Seat Conversion

The Mikuni diaphragm carburetor, once known as the Burco Super Carb, has been a commonly used item on unlimited/open 2-cycle engines for decades. There is a good reason for that, the carburetor is relatively easy to tune, is very reliable, and produces good power. Unfortunately, many of the parts are no longer in production making it necessary for racers to replace an otherwise good carburetor for lack of replacement parts for high wear items.

One high vear item in the carburetor that simply must be replaced from time to time is the inlet needle and seat. Many engine and carburetor tuners replaced the original Mikuni needle and seat with a ball jet valve or Grose Jet as it is more commonly known. Several years back the Grose Jets went out of production and are now next to impossible to get. This is very unfortunate because when this valve wears it leaks causing the carburetor to load up at idle speed and when negotiating slow corners. When replacement valves were readily available, replacing it was sort of a mini tune up that would restore crispness to the operation of an otherwise healthy race engine. For a while, racers went back to the original Mikuni needle and seat but all of that old stock has long since been used up.

Bergfelt Racing Enterprises, LLC, in seeking to provide the best service for their customers, sought and discovered a needle and seat that can be adapted to the Mikuni carburetor. Installation does require redrilling and threading the original hole that receives the valve. Bergfelt Racing Enterprises, LLC is pleased to offer the service of installing their needle and seat in Mikuni carburetor bodies. One other advantage of the needle is that is has a large neoprene tip for positive sealing.

To have one of these needle and seats installed in your Mikuni carburetor body, just send it to us and we will do the rest.

Bergfelt Racing Enterprises, LLC

Needle and Seat for Mikuni Diaphragm Racing Carburetors

$39.95 installed-includes needle and seat.

Diaphram and Gasket kits are also available.


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To order call (724) 462-7440
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