I found this thread via google and signed up for the forum because I have a similar problem with my '03 Foreman 450. I'm not sure if I should have started a new thread (well I probably couldn't anyway since this is my first post).
I recently got back form school and have been riding her almost every day for the past two weeks. It's been very cold up here in Northern Arizona so she takes a few tries to get started with the choke but idles nicely.
Today I rode about 2-3 miles and she was running fine and luckily nothing happened until I got to my destination. I was cruising in 4th gear and when I let off the throttle I felt the quad bog down and lose power. I shifted down into 3rd and gave some gas but there was little to no throttle response so I shifted to 2nd and 1st with the same result. As soon as i completely let off the throttle and came to a stop the quad shut off by itself and refused to start back up. It felt as if I were running out of gas, and I've only done that once, two weeks ago.
I got her to a buddy's garage and tried numerous things. First I took off the filter and sprayed starter fluid into the carb while trying to turn the engine over. No dice. Next, I tested the wire to see if it was firing. It produced a spark and I turned off the kill switch and tried again and there was no spark (just to check the switch itself). I pulled the spark plug, cleaned it off and tested the plug with it in the wire and there was spark. Also checked the fuses and they're all good.
Then I drained the bowl of the carb, primed it and it still wouldn't turn over. I unhooked the hose from the gas tank to the carb and there is gas flowing. There is also gas getting to the inside of the filter tube where the primer pumps it in.
I'm kind of at a loss of what to do.
Right now when I try to start it I can hear the engine cranking but nothing else. I'm not sure what would cause it to die on me like this. Luckily this didn't happen last night when I was coming home from a night ride.
I don't know if there is gas getting to the engine.
Maybe the carb is clogged? I ran across this thread and am going back to the shop to take apart the carb to see if that is the culprit. I'll do what Rich mentioned in another thread and boil the thing in lemon juice.
I have fire, I have gas, I have air. It seems like something electrical might be preventing this from starting since it worked well the past few days.
I just recently changed the oil, if that is of any question. I know some honda small engines like my generator have an automatic shutoff when there is no oil.
I will let yall know what happens when I tear apart the carb. I have never done it before but if I just take everything off and remember where it goes I should be fine right? Maybe i'll do a quick search to make sure.
Thanks in advance for any ideas, tips etc! I love forums!