My quad will not tick over or start when hot. It starts fine first thing ticks over for 30 seconds, starts to splutter dark smoke from exhaust and stops. Had to adjust it to tick over real fast to keep it going. When throttle is open bike goes well no dark smoke. It's as if the choke is on but it's not. Any help would be great.
Here is where I is. Disconnected pipe between air filter and carb started bike no difference, cheched choke slides in and out smooth as you like. Have now removed carb and it is remarkably clean have blown out any way. There is a load of rubber tubes one of which goes to a thingy on the exhaust so thought I would reassemble start up and try pinching each pipe in turn to see what difference it makes if any. But the broblem is only on idle. See I will make a grease monkey yet or may be not. Thanks fellas keep you thoughts coming.
The carb is a mikuni bsr 36-89 with a butterfly throttle and a diaphragm at the top with needle valve and plastic slider which restricts the air flow through the carb. If I hold this slider up with my pinky it tick over real good but cuts out when you open the throttle, (for those that have not lost interest yet) let the slider go and it runs rich and stalls but will pick up if you open the throttle befor it stalls.