Hey guys I've got a 2003 Suzuki eiger 400 manual and when I'm riding it at a higher rpm then let it coast for a bit it will backfire. Can anyone help me fix this. I don't have much experience with this kind of stuff.
Go get a can of sea foam and follow the instructions on how much to add and then add a little more. I try that before I ever grab a tool.
Take Sota's advice, it's a good start. Generally caused from water in the fuel system. If that doesn't clear it up after some running, I'd try changing the spark plug and check the wire for damage. I have a 2005 King Quad, it had a similar problem and was the spark plug. Changed it out and it ran great until it rained and then it wouldn't even start, turned out I didn't get the spark plug wire seated well in the spark plug hole and it leaked water in around the plug and shorted it out. I blew it out with air and it worked just fine.
Yep, agree with both above. It's either not firing properly or there could be water in the tank/line. Sea Foam works great by the way, it will go a long way.
Checked the spark plug and it was white. That means it's lean? Would it have anything to do with the backfire when coasting down from a high speed?
Was it a whiteish crust? Sounds like ash deposit if so, could just be normal from the type oil you have in it or the gas or it could be from some excessive wear in the engine. Either replace it or clean and gap it and reinstall it and see if it helps the problem and if so, how long does it remain improved before it fouls the plug again. I'd go back with a new plug though personally. May well fix the problem for a good long while.
Changed the plug and made a very small fuel adjustment to the carb and doesn't backfire when I coast and it feels good as new. It still does the little backfire when I shut it off. Similar to what people call the grizzly fart since it's common in the Yamaha grizzly's. I call it the eiger fart since it's a eiger. Thanks for the tips guys I'll probably run some sea foam later just to be safe.
You might have a dealer check to make sure there is no recall on the machine. I had a factory recall on mine right after I bought it to replace the ECM on it. I think it changed the air:fuel mixture and maybe the spark timing.
I actually found another problem to why it could be backfiring. It did it again and I read a little and found out it was an exhaust leak. I'm going to get some high temp silicone and put some on there.
Tightened the front of the mid pipe and so far it hasn't backfired since. I've been riding it for 3 hours.
