2026-06-01 Carb Diaphram Washer Replacement

had previously rebuilt this carburetor. But when I installed it on the bike, it was not running good.

The previous owner had installed some kind of a kit where the middle washer.
On top of the diaphragm was replaced with a plastic washer. My guess is they were hoping for faster throttle response.The problem is that the plastic washer overtime had deformed thus presenting a vacuum leak.
So today's job was to find a suitable washer, fabricate it, and install.

I went to the hardware store and sourced several washers of various diameters, thickness, and weight

I decided on this one.

 17 grams. 
 

1.38 mm thick.  
 

The center hole is 1/2 inch, outer diameter is 2 inches. 
 

Now for the fun part of drilling holes. I don't have a drill press so I'll have to do it with a hand drill.
 I used the OEM diaphragm, plunger, sub, clamps, and vice to ensure I drilled in the correct location.  
 

Drilling complete. But I really do need to buy a drill press.  
 

A better picture of the setup.
I had to be very careful to keep the drill square and not hog out the OEM plunger holes.
 

Here it is installed. I later removed this diaphragm and replaced it with a far superior one from Zed Parts, based in England. 
 

I used a 9/64 inch bit to drill the holes into the washers.
 

 

Any comments, good or bad? 
Any suggestions?

I only post what I'm doing as a learning experience. 

...and hoping for advice, suggestions.

Don



 

Do you have an OEM washer that you can compare the weight of looks like your new one might be a little heavier?

stocktoy wrote:

Do you have an OEM washer that you can compare the weight of looks like your new one might be a little heavier?
 

I do, just have to remember which of the 6 racks has OEM parts in it..

Kawboy, myself and stanG did write-ups about these spacers  Do a Search

scotch wrote:

Kawboy, myself and stanG did write-ups about these spacers  Do a Search
 

2 hours later and still haven't found the posts. I'll keep trying. Lots of other good carb reads tho...