[DanR]

I looked for a while before I ordered from China. Others did have them but at close to 3x the cost and/or still overseas shipping. You can also find just the rubber part to try and fit to your old piston but again, same price or higher and I didn’t trust that I wouldn’t screw it up.

 

[DanR]

This is the other part I mentioned. 86-87 HONDA CMX450 CMX 450 REBEL KEIHIN CARBURETOR 16111-MM2-771 SLIDE DIAPHRAGM | eBay

 

[DanR]

I bought these and can verify they fit and work great.

MEMBRANE Diaphragm Carburetor Vacuum Piston For Honda CMX450 1986-1988 1987 | eBay

1 Piece Carburetor Vacuum Piston. Front Inner Fork Tubes for Honda Suzuki Kawasaki. Front Outer Fork Tubes for Harley BMW KTM Honda. Preload Front Fork Bolt For Honda NSR 125 SP. Turn Signal Light Switch Cable For Honda VFR400 NC30.

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