I've been following this thread for two months. What began as, to me, a rather dull "What's your mileage?" thread has evolved into a carb tuning conversation. Much more interesting.
I now have something to add. I'm traveling in reverse with comments to the recent posts.
It's often said that worn needles and needle jets cause poor consumption so they may be worth looking at. My own view is that the idle settings are crucial to good economy. ...if your idle settings are too rich it will hurt overall economy by more than you might think.
Very true. Barry reinforces the importance of correct mixture and idle stop screw balance above most all else. All other adjustments are built upon this primary foundation. Good mileage is one result.
I'm getting about 40-42 mpg. I'm a little bummed about it. In my research on this model I was lead to believe that I'd get more like 50- 55.
If the mileage expectations came from factory literature,
sorry. 112 pound BMW test rider Gunther wore his skivvies and a t-shirt as he half-coasted around a flat test track with tire pressures near explosion levels and a mileage test fuel bladder holding a single gallon of fuel. Jawohl, mein Hauptmann. Fifty-five miles per gallon!
Reading through the mileage posts, I note differences in the R65's load, type of road, terrain and
wrist action. We're discussing a 650cc motorcycle that has a factory spec weight of 452 lbs (R65) or 456 lbs (LS) with full fuel and a tool kit. Both bikes are rated for a maximum load of 423 lbs for an average of 877 pounds! Big load out equals a big grab of throttle for hiway cruising.
The Bing manual shows five different models of carburetors fitted to various R65s. The 1981 runs 325-326 while the 1983 has 335-336 seres Bings. Both bikes deliver around 43-46 mpg, my style.
