JBM Industries

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Yamaha Teikei YDLS XT350 & SRX 250 Carburetor Diaphragm Installation Instructions for JBM Industries Replacement Diaphragms.

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$19.50 USD

Parts for these vintage TK motorcycle carburetors are hard to find, and if you need a new diaphragm, you have found a source right here. Great to have as spares as they are light and easy to carry along with you. Easy to install, even on the road or trail. Also fits Mikuni BS30 & 28 used on some YX600 & FZ600 & XJ550.  63mm outer groove diameter. Yamaha Duo Intake System ( YDIS ) NOTE:  Some Tekei TK have a 68 mm OD diaphragm and can use our H-68

Installation Steps

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Step 1

To install these diaphragms you must first cut off any plastic or metal retaining rings using side cutters. Cut is several places and twist the cutters on metal rings.

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Step 2

Be sure there are no sharp edges and install as shown. Rubber has very little stretch, and the central hole in diaphragm is slightly smaller than the slide.

BE SURE AIR HOLE IN SLIDE IS IN CORRECT POSITION on engine side of slide:  This Yamaha YDLS carburetor has two barrels, one working mechanically, and the other opened by vacuum. CV type carburetors allow the use of very large carburetors, as they will only open as much as the air drawn in will allow. As revolutions increase, the slide will open to prevent stumble or cutting-out. Yamaha single cylinder.

This TK-63 Diaphragm can be also used on a Mikuni BS-28 as shown HERE.
HISTORICAL DATA: Teikei Carburetor