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melted airbox!!!

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Background: Bike hasn't been started in about 5 months. I had knee surgery last year which prevented me from doing any riding. So I fire it up tonight, took about half hour to get it to run, sort of. It sounds like poo, pops shoots flames out the exhaust and stalls out. I am attributing the running problems to old crappy gas.

Now here is the Question. After it "ran", I noticed smoke steadily rising from either side of the side plates. Upon removal I noticed the exhaust had melted the airbox. The exhaust and airbox are both stock. Never had this prob before. Now what would cause that and also, should I replace the airbox?? Not a large hole, but still a melted hole. The bike is an 06' 450. thanks.

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drain the old fuel and pour in some fresh fuel. see if this doesn't help with the popping. as for the hole, if your not too concerned with looks, patch it.

keep us up dated.

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thanks, I was concerned about water and crap getting into the airbox. For $100 I can get a new airbox assembly. I am going up to Hunter Motorcycles tomorrow and see what they have to say. I will keep you updated and post some pics tomorrow.

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If it was running fine 5 months ago then the popping was most likely caused by lean jetting as it is colder around there than it was 5 months ago. Was the exhaust touching the airbox where it melted?

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nope. The exhaust and airbox are stock. Never had a problem. bought bike new. Should I pull the carb and see if the fuel gummed up. I don't see how it could in such a short time. I did forget to use sta-bil. Supposed to go riding saturday at ace. Hopefully I can make it.

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nope. The exhaust and airbox are stock. Never had a problem. bought bike new. Should I pull the carb and see if the fuel gummed up. I don't see how it could in such a short time. I did forget to use sta-bil. Supposed to go riding saturday at ace. Hopefully I can make it.

The gas we get nowadays turns to varnish in as little as 3 weeks. If it sat for 6 months you need a carb clean for sure. I'm kinda amazed it even started. If i am not going to race for more than 2 weeks. i always just pull my pilot jet out and clean it. Its always a little clogged up even after a couple weeks.

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Just a quick update. I dropped the bike off at the shop. My guy there said that he never saw something like that before. Hopefully the factory will replace the airbox at no charge. I doubt it. lets see what happens.

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Just a quick update for anyone who cares. I got my bike back, the factory covered the cost of the airbox. It turned out that the bike ran to lean and that caused the exhaust to get to hot and melt the airbox and rear fender. So make sure your ride runs right. Safe riding.

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Im glad they covered you

For the life of me, I cant believe the factory covered that.They are ususually tough to get free parts out of even if its the fault of the design of the bike.

You must have a good dealer.

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