A few days ago my father with his banshee and I on my trailblazer took a trip up to pennsylvania to go riding in the tower city area. About 1 1/2 hours into our riding, going up a hill, approx. 30 degrees, my trailblazer lost power and died. I turned around and rolled down the hill to check things out. Eventually the plug was pulled to reveal a gray color with what seems to be melted metal on the surface. Somehow the bike lost gas up the hill to make it extremely lean and die. Then the fuel line was checked and fuel was flowing freely so what happened? Also, coming form a lower altitude the air-fuel mixture should have been richer and not leaner to cause such a problem.

Then after these and a few other checks, we knew the bike had air fuel and spark but after 40 minutes at rest it refused to start, WHY?

Any of your help is appreciated! LMK if you need any more information.

 

It sounds like maybe the bike just over heated. If you found melted metal on the spark plug, that is a problem. It sounds like you melted your piston. The reason for it not starting would be because your piston is damaged.

That is just what I think it is.
Anyone else?

 

Did it make a loud pop sound when it stalled or did it just bog out?

 

I was at 1/2 throttle going up the hill but 3/4 of the way up the hill I started to lose power and gave it more throttle but there wasn't any more power to be had. Right before it died it did backfire/pop.

 

Looking at your sig, you have added significant air improvements, but I see no jetting mods. With the injection removed, your quad has the same oil/fuel mix all the time.(not really good)

Sounds like it should be running lean all the time. Did you recently perform these mods or has it been this way awile. I guess the question is, how many hours do you have on it with these mods?

 

I second the overheating theory. I have a melted piston setting in front of me right now that reminds me of the bad memories. Put you a compression gauge on there and see what you read. Or you should be able to tell just by pulling on the rope if you have any compression. Check your cooling system, mine was caused by me because I forgot to tighten a hose clamp, and I let me buddy's girlfriend ride it, who didn't know what that temp gauge was for. A hi price to pay for a loose hose clamp.

 

brent87LT1, it isn't listed but the carb has been tuned as well. If I remember correctly it has a 130 main jet and 40 pilot jet. And the gas & oil mix is 36:1. With this setup it was not running lean. These mods have been installed for just under a year and I ride for about 1-2 hours about two or three times a month.

400fnSport, the compression is worse than before but still ridable. My cooling system consists of an air cooled head but the bike didn't seem to be creating any more heat than usual.

 

Well sounds like it's not hurt too bad. How does the rope pull? Does it feel like there is something abnormal going on in the cylinder?

I'm sure by now you've tried it with a new plug.