I don't know if you're aware of it or not but most of the fasteners used on this bike are not standard metric ones, they are the J.I.S. type (Japanese Industrial Standard). This doesn't affect the threads, they're the same as normal metric fasteners, but it does affect the nut, bolt head, and screw head sizes. For instance, a normal metric M8 nut or bolt will have a 13mm head size, take a 13mm wrench to install/remove. The J.I.S. M8 has a 12mm head or nut size. But the bigger deal here are the Phillips screws. They're not really Phillips any more and are referred to as cross-points, and they need a different type screwdriver to fit them properly. A normal Phillips doesn't fit into them very well. You may notice many of the Phillips heads on the bike are buggered up, this is why. I'm telling you all this because the throttle shafts use these J.I.S. cross-point screws to hold the butterfly plates in. On top of that, the ends of the screws are crimped or peened to prevent them from backing out .....
This makes them difficult to remove so I suggest getting some proper J.I.S. type screwdrivers before even attempting it. Also, the throttle shafts are made of brass so are soft. Try to remove the screw with their peened ends still intact can mess the threads up. So, I like to grind off the peened end first using a small ball cutter in a Dremel .....
Also mentioned was the fact that the shaft seals can be had from Suzuki for a better price, way better now because the Yamaha price just spiked to $18, lol .....
This Suzuki seal is the exact same part as the Yamaha one. Suzuki used very similar BS type carbs on many of their bikes.
