After a 2-year restoration of my RG250 Walter Wolf (mine was pretty "rough"), I now have something like 1,000 miles on her and one thing is that mine is showing is TERRIBLE gas mileage.
As a collector of SuzukiI 2-strokes (I have 33 bikes including my RG500, RG125, RG50, GT750, GT380, GT185,T500, X6, A100, TS250, TS250X, TS185, TS100, TS90, TS50, etc) I am prepared for less than stellar MPG, but my little RG250 gets something like 22-24 mpg even when riding as mellow as practical. Trying to sniff around... I'll be happy to break 30mpg, but so far not even close to that! This about the same as my Mercedes E-320, and much worse than ANY of my other bikes (RG500 , GT750 included!)...
Let me know if you have any ideas and I will also share any of my findings! Compression is 140psi on each side, so topp end seems in pretty good shape (not new). Lf plug looks good (brownish electrode), right side is black and wet, so will start investigating there. So far, jets are the same on both sides, so thats not it. When running, the temp is pretty normal. So far I have "leaned" the needles one position (moved clip "up" one groove)... seemed to clear the middle range a tiny bit (more to go, but one step at a time when is comes to carburettors!)... not much change to the MPG as expected... I will keep you posted... my next step wil be to replace the Jet Needles and Needle Jet as I understand these get "opened up" over time as the needles bang around the "holes" on higher mileage bikes! Cheers! Vm