Sherco Kits
We have finally gotten ahold of a Sherco 290 here to develop an OKO carburetor kit for it.  We replaced a DeLorto 26mm that was hard to start with idle issues.
This was not a "Plug and Play", but no serious mods were needed.  The spigot on the DeLorto was smaller in diameter than the OKO and therefore a very tight fit.  We decided to Dremel the hole out about 1mm to better accommodate the OKO's spigot.  Also, the inner cable was too long due to the DeLorto's curved top.  We cut the end off at the throttle, placed a barrel end with a set screw on it and cut off the extra cable.  The throttle cable end is included in the kit.  Space was tight and the bowl went right against the rear brake fluid reservoir, but it fit.  There is only about an inch gap between the carb intake and the airbox spigot, and the holes were offset.  We cut a 2" ID sleeve on a bit of an angle and tightened each end with hose clamps.  The OKO gave nice, smooth idling, great throttle response and overall better performance.
Currently, we don't have a kit for the 250cc, but we do have carburetor size and jetting, so  a 250 carb can be ordered and the rest will be "Do It Yourself".
The kit for the Sherco 290 includes a 26mm OKO jetted for it and comes with extra jets for fine tuning and elevation changes.  Also included are a throttle cable end and a sleeve for the air box.  These are all you'll need for the conversion.  Select either the 290 kit or the 250 carburetor alone, and select the shipping destination.
Select Kit & Destination
Color of Carburetor