NICECNC Air/Fuel Mixture Screw Adjuster for MIKUNI BSR BS CVR CV Carburetor Compatible with Suzuki DRZ400S DRZ400SM,Gold

Worked perfect on my 2001 DRZ400S with the Mikuni carb. Previous owner lost the spring, washers and o-ring, giving me an erratic idle. For the cost of just they parts from the dealer, I now have an easy adjustment screw. Must have for any DRZ

This MICECNC Fuel Screw (or "Idle Screw") worked great in my 2014 Suzuki DR650 stock Mikuni BST40 carb. It included the tiny washer & o-ring, it installed easily & protruded below the carb enough to easily adjust ide mixture. There's none of these available elsewhere on Amazon for the BST 40, so for $20 they're a great value. Fyi, my '14 DR650 with stock BST40 carb, air filter (snorkel removed) & 42.5 pilot jet only needed @2.25-2.5 turns out for a perfect idle. Fyi, this screw's tip 'taper' is slightly more pointy than the stock idle screw, but it doesn't matter in it's function, I only wish the threads fit a little more tightly/more thread tension into my BST carb, but otherwise it works perfectly for the Mikuni BST 40 carb.

This works great and it's much easier to dial in my carburetor compared to trying to get a screwdriver or flathead bit in there. My only problem is that when it was adjusted to the same setting as the old fuel screw, it was a bit wobbly. I worried that it would vibrate out on a ride and be lost, so I had to turn it in a bit more for it to be secured. Maybe a small bit of plumber's tape would secure it?

No complaints about this item. Installed it in my stock DRZ with the JD jet kit and MRD full exhaust. I'm around 3k above sea level and have it set at 2.5 turns out. It runs amazing, I didn't think this bike would ever run this well. Getting the original screw out was tricky, I drilled too far getting the plug out and took off most of the head. Had to drill the top of the screw and remove with a torx bit tapped in the hole. It worked, but be careful with that when you try to remove the stock screw. Honestly don't see a point in upgrading to a better carb with this setup.

The placement of the fuel mixture screw on my carb is impossible to get to without special tools or removing the carb. This things solves thay problem and makes adjustments fast and easy. Make sure to install the o rings properly.