Well this is my first xr70 (had a xr50 before) and I just cant seem to get the thing to idle. It will idle better with the choke on but with it off I have to keep playing with the idle screw to keep it running. It seems to idle good for a minute and then wants to die. I already cleaned the carb out and it has stock jets. Is there any issues with these bikes like valves or anything of that sort, thanks.