[Neeko's]

I have a 06 ltr 450, a mechanic has recently rebuild the engine so it started and ran pretty good other then it would bog a lil bit, so I changed the fuel, put a new fuel filter, new spark plug, and now when I try to start it it backfires and won't start, anybody got an advice what could be wrong?

 

[krigepj]

I have a 06 ltr 450, a mechanic has recently rebuild the engine so it started and ran pretty good other then it would bog a lil bit, so I changed the fuel, put a new fuel filter, new spark plug, and now when I try to start it it backfires and won't start, anybody got an advice what could be wrong?

Have a look a your idle air screw I also had a problem with starting and backfires when I decelerate into corners. I closed the air screw and opened it 1 and 5/8th turn open according to manual spec. Mine was about 3 turns open, which is way too lean and after I adjusted it my quad was running smooth, backfiring just now and then on some deceleration.

 

[Neeko's]

I got it to start up finally, but after like a 5-10 minute drive it starts to bog and then just dies out
Any advice what could be wrong on that?

 

[krigepj]

I got it to start up finally, but after like a 5-10 minute drive it starts to bog and then just dies out
Any advice what could be wrong on that?

I also had an issue with bogging and die with my previous LTZ 400. Also looked at all kinds of fuel issues, then found that my spark plug coil connector plug was loose and when the quad got hot it would not make proper contact to the coil and the quad would bog, backfire and die. Just another thing to look at.

 

[Neeko's]

Thanks for the advice!!! I'll definitely try that