I just bought an 03 400ex and it doesn't want to start i have to pull it behind my truck for 5 minutes to make it run. when it finally starts up the exhaust pipes start glowing. it has a slight backfire out of the carb too. what could be causing this.

it has a curtis sparks exhaust and 165 jet. I have no idea if thats the right jetting for this bike. Its how I bought it. and it was sitting for a while so the carb might be a little clogged I really have no idea. Any help is greatly appreciated.

 

Welcome to the forum. From what you're describing. It's probably starving for fuel. I would start by cleaning the carb. and getting a new spark plug. The jets are probably clogged from sitting and when you finally get it started the pipe is glowing from it running lean due to the jets. Running it lean like that is really bad for air cooled engines.

 

if I take the carb off to clean it i will change the jet and i'm curious what the proper jet would be for this setup. personally I thought 165 would have been too big

 

If the exhaust is glowing, I would say your jetting is off, could be because of the cooler winter temperatures too...

 

all depends what kind of jet it is.put a 42 pilot jet in that will help start it a lot easier.and clean the carb really good.let us know!!!

 

glowing red at idle???????? sounds like the pilot jet is clogged.42 pilot works wonders you wont even need the choke.

 

165 I would think would be close enough to keep it from running like that. A carb cleaning sounds like where you should start for sure.