Got an 05' Brute 750. After it sits for 2 weeks or more it is extremely hard to start. It usually takes about a good minute or so of cranking and letting starter rest about 10 sec. before it fires. then crank another time and it will start up and idle fast like normal on full choke. After warming up it's fine. Starts right up after sitting only a few days. Sits 2 weeks or more and hard to start again. Anyone else have this problem? Any ideas? Dealer said drain both carbs if it sits longer than 2 weeks due to todays cheap gas. I don't buy that.

 

I do.

Today's gas is not cheap but it has more ethanol than old days. What it means is that gas is more likely to:
> have separation phase sooner
> attract H20 from air (when tank is not full)
> attack rubber parts in fuel system
> leave gummy residue in carbs clogging pilot jets

It sounds like your carbs' pilot jets are partially clogged up and/or choke plungers are partially sticking, not opening all the way, even when you push the choke lever on the left side handlebar all the way to the left.

Either carb cleaning is needed or need to run carb cleaner in the gas tank. Once that's done, start using Fuel Stabilizer if you would not be ride the quad more than 2 weeks or longer.

 

Reason I don't buy the cheap gas idea is beacause I have an 06' Kodiak (carb) that can set for 2-3 months and all I do is set the choke and bump the start button and it's running. Owned alot of atv's in past few years and never had this problem. But I have considered having carbs either taken apart and cleaned or using carb cleaner in tank. Thanks for reply Hayashi.

 

I had a similar problem on my 2005 BF. I adjusted the valves. Starts right up when choked after days of sitting. If it has ran recently it will start without choking. It even starts a whole lot better when it is warm. Have you done the valve adjustment?