From the Madura site:
2583.1 In January of last year while checking the sync on my carbs, I noticed #1 & 3 cylinders, fluctuating badly on the mercury gauge, while 2 & 4 were steady as a rock at 18cm mercury. So, I started checking for vacuum leaks, and ended up finding them caused by very small tears in the slide diaphragms on the carbs.
After pricing replacements through Suzuki ($120.00 per slide assembly) I decided to create a repair that would work.
I've waited just over a year to post this, so I could be sure of the reliability factor.
The tears in the diaphragms were caused simply from the movement over time, causing a slight crease and weak spot in the rubber, which finally lead to a small hole. Both of my slides had holes not much larger than pin heads, but under vacuum, they caused leaking, hence the fluctuation, and lack of throttle response.
I made the repairs by buying a box of latex surgical gloves, a tube of clear silicone adhesive, an artists paint brush (with bristles 1/4" wide).
Remove the affected slide, and thoroughly clean the diaphragm with mild dish soap, warm water, a cotton ball or Q-tip, to remove any dirt, residue, etc, for good adhesion when applying the fix. Air dry with low air pressure or hair dryer.
Using one of the latex surgical gloves, (Note: these will have been coated with powder to make them easier to put on your hands. So you will need to wash them as you did the diaphragm to remove the powder) cut a small round patch out of the glove. I made mine 1/2" diameter.
Using the clear silicone and the artists brush, paint a thin even coat of silicone over and around the tear. place the patch you've mad over the tear, centering the patch over it. Wait approximately 30 minutes, then again using the brush, place a thin even layer of silicone over the patch, overlapping the edge of the patch a 1/16" or so. Allow the patched slides to dry overnight for complete adhesion, then reassemble and check carb adjustment.
As I said, I made this repair a little more than a year ago, and yesterday, I pulled the slide covers and using a strong magnifying glass (old eyes ya know) I found NO further deterioration of the diaphragms or the patches I made. And on the mercury gauge, the carbs are rock solid, with NO fluctuation. I've also since done this same repair to 2 Harleys, a Suzuki Cavalcade, and a Kaw Vulcan, all with the same reliable results.
Hope this saves some folks some money.
