I have a 2006 Yamaha 350 bruin, having lot's of problems with it. Start's right up idle's pretty good try to give it throttle and will bogg down, what I have done and checked. replaced coil have had the carb. off several times recleaning it checking to make sure everything was right, checked diaphragm no holes adjusted carb many times. cleaned tank taken shutoff valve off and cleaned it and the filter, new fuel line and filter. new battery, new ignition switch, new wiring harness new switchs on handle bar for starter button and run switch, don't know what else to do any idea's would be greatly appreciated.

 

Does it "bog down" if you are on choke with the engine part warm?

 

yes it does , the choke will pull it completely down with half choke and trying to give throttle it still will die. it starts right up with out the choke, but at 1/4 throttle it will bogg downand die there is no feathering the throttle and slowly bring the rpm,s up it just dies. I can let it set there and idle for thirty or fourty minutes then gas on it and still it will die, don't know what ells to do , aany help I would really appreciate it.

 

Could be water contaminated fuel. Water settles at the bottom of the tank and carb bowl and an engine can idle but stall out when you give it throttle. If you eliminate that along with any air leaks,dirty air filter and it still does it,could still be trash in the carb or a simple carb kit may solve the problem rather than just trying to clean one up. 2004 2006 Yamaha 350 Bruin 2x4 4x4 Carb Carburetor Repair Kit YFM350 03 321 | eBay

 

taken tank off dumped out gas cleaned tank, took petcock off cleaned it both screans out put new fuel line on, had carb off eight times all holes will blow through with air, checked flote level many times, just don't know?

 

Is the piston in the carb moving smoothly? Is it the right way round? The colour of the plug nose would give some indication, white and the carb is running weak, not getting enough fuel when accelerating, black and the carb is rich, and the extra that the carb squirts in on acceleration is just too much. A repair shop would have swapped carbs by now, thus eliminating the carb as a problem or confirming it. You haven't mentioned changing the plug, coil, rectifier, or ignition trigger unit. Any of these can cause odd faults. I would change the plug and check the voltage across the battery with the engine running to see if the regulator is working properly, over 15v and it is bad. Putting the Bruin into a repair shop may be cheaper than fitting new coils etc, which may not cure it.

 

well got new carb kit, put new kit in carb rechecked float level checked plug no problem there. I guess I have a electrical tipe problem.

 

IMO I think its past time to take it in to a repair shop. Either way you've put a lot into it and you still can't ride it. Its hard to know when enough is enough.

 

can't afford to take it Yamaha and have them rake me over the coals for the tune of 5 or 600.00 dollars, surely there is a reason for this and I am going to find it. it was running before just fine' road it one day set for a couple of days, then it started.

 

I'm in the same boat as you but just add up everything you've changed and the cost and it still doesn't work.