Backs 400 wrote:As for the throttle..the cables actually pull the thing open or shut (alledegly), so sticking is not normally a problem....
No they don't , the throttle return springs should close the carb slides , unless there is too much friction in the cables for the springs to overcome , or it could be crap in the twistgrip not allowing free movement
It may be as simple as the mechanic has used the wrong lubrication in the throttle cables , some cable liners are not supposed to be lubricated and putting oil down them damages the lining and makes the cable stick , with a bike as old as Joans there is no way of telling what cables have been fitted
If you open the throttle , let go and the twist grip does not return to closed on it's own something is wrong.
The slow rundown on overrrun which you describe your bike doing is bad carburation or clogged jets , this would tend to happen more to older bikes or bikes which have been badly serviced or where the carbs have not been balanced correctly
