xs250 gaz

hi got a neighbour whose been given a townmate 80cc as part payment for a job,it's in cracking condition for year(88)but slips out of 2nd under heavier work(hills),he's wondering firstly what's likely to be the problem(he suspects selector)and if it's straightforward and cheap to repair himself or just sell as it is?any of you got experience or knowledge that could help?cheers

yeah start with lever up.ultrasonic?!sounds expensive!not sure what it means?

hi bought xs250 and found it won't start when the choke lever is pressed down(it's like i pressed the kill switch,nothing!).but with a bit of nifty throttle work i can get it going ok(although through winter it's not been fun).do i need to replace them or can i fix em?once running and warmed up they run sweet.help!