My little brother just got a 250ex . I took it for a ride and almost every time I let off the trottle it pops a little? It is brand new! What could be the problem?

 

You may have an exhaust leak.

 

how could I check if it has i exhaust leak?

 

how is it poping it could b the clutch no? clutch slip.

 

I was riden in like 4 gear and was goin pretty good. The just say i let off the gas quick and fully. the exhaust will pop. If you actually put your hand behind the muffer you can feel the axtra pop of gases come out. I dont know what it could be. I was thinkin maybe jetting is off ,but it is stock and brand new!

 

if u r riding at high altitudes or really low altitudes (like death valley or something) then it might be the jetting. take it back to the dealer and talk to them. if something is wrong it should be under warranty.

 

it could be the following

------------Plug is fouled ( odd for a 4 stoke)

------------ not broken in correctly. should run it light for atleast the first 2 tanks of gas.

----------- or u just got a messed up quad. Take it back and throw in thier face. They deserve u pay that much . something wrong alrdy?

 

Check that the head pipe is tight in the head. check the exhaust flange. check all exhaust pipe joints. Visually look to see if you can see anywhere that exhaust gas is leaking. I would take it back to the dealer if its new and let him deal with it.

 

I remember reading somewhere that if you break the engine in by driving it hard, the rings tighten better inside the cylinder and down the line you'll have more performance.

 

Their are way too many theories on how to break in a motor![img]i/expressions/face-icon-small-confused.gif[/img] At the risk of being flamed this was how we did it. We would heat cycle the motor three times. Then run it verying the throttle for a couple of laps. After that they were good to go.