I wonder if anyone can help me. I have a 2004 1/2 sportsman 500 with about 450 miles on it. Last week we were at the cottage it was about 20 below. I started the bike had the choke partialy on. It ran about 3 minutes and there was a bang I thought it back fired but saw oil on the ground. I shut down the bike immediatly. The side of the oil resourvoir had blown out. My question is why did pressure build p in the resorvoir to the point it could do that. I have a new one but am leary of putting it on till I know the cause. The dealer could not explain. PS I walked 6 miles out of the bush...not fun
Thanks
Fallon

 

Wow..this is a first that I've ever heard of this happening..so it blew out the side of the oil reservoir? If you can could you take a couple pictures of it, I'd like to see this.

 

my wife has the same machine and I had to look at what was up. I'm not much of a mechanic but was wondering if moisture had built up in a breather, froze and thus created pressure in the reservoir.

 

I will take pictures tomorrow. Moisture is a possibility. It was very cold but I am not sure what could cause the pressure to build unless it was the oil heating and expanding. When I go back to retrieve the machine I will check the vent linr. Thanks for the replys.

 

That's one heck of a problem. I can't believe the oil pump would produce that kind of pressure but obviously something went wrong. I suppose the cold could have done what you suggest with freezing the moisture but wow. Thick oil...I don't know. Did it have the proper oil weight in it?

 

im sure it had to do with moisture freezing in the lines possibly.... just an oppinion... with oil viscosity being the way it is i wouldnt be running that machine in that cold of weather