This OKO carburetor kit was developed specifically for Yamaha SR500, TT500 and XT500 to replace the Mikuni 34mm.  We fitted and jetted an OKO K-104 PWK 36mm to our SR and got very good results.  The engine pulled strongly through the throttle range with very good throttle response. Our engine had some mild mods so we include extra jets for fine tuning.  This carburetor fits directly into the stock manifold.  We include a new Universal Venhill Throttle Cable since free length is different from using the Mikuni.   Cable comes with a barrel end with a set screw so soldering is eliminated.  Contact us with any questions.  We will reply within 24 hours.  Full refund if not totally satisfied.