I own a LTZ400 and the other day I was messing around with the exhaust pipe and so i cut out the screen in the cap at the back of the pipe.....the bike sounds good and the high end is performing great....compared to my roommates stock version it seems to have an edge....here is the problem...when the rpm's drop down to approx idle speed the engine stalls....it is also running very rich....

this is very frustrating to me so i am seeking any advice anyone has to have...

 

You might need to re-jet if you increased the flow enough to make that much of a difference....... At the very least try running it with the air box lid off to see if you can get it to lean out a little bit to diagnose the issue....

 

I am having a similiar problem. When RPM's drop it stalls. Also, when I start it, it will idle and if I put the clutch in without giving it some gas, it will stall. What is wrong?

 

You can also try adjusting the fuel mixture screw on the carb. try backing it out a half a turn to see if it leans it out.

 

<div class="FTQUOTE"><begin quote>Originally posted by: chris672

I am having a similiar problem. When RPM's drop it stalls. Also, when I start it, it will idle and if I put the clutch in without giving it some gas, it will stall. What is wrong?</end quote></div>

we had this issue and just adjusted the hand clutch lever and it seemed to fix it, as clutch was engaging with no freeplay.

 

If you take the spark arrester out, you need to rejet. You are running too rich...

 

I still have stock exhaust. I think it might be the clutch lever because It started stalling after I changed the handlebars and levers. I will try that first. Do I just adjust the nut by the lever?

 

yes adjust the nut on the lever . and removing the spark arrester should of leaned it out a little not make it rich unless you have the choke on a little

 

wont taking the spark arrestor out make it run lean because the air flow out is increased so it will bring more air in. because when you buy an aftermarken pipe they have you put a bigger jet in the carb.

 

it might be the carb so look at elm or it might be exhaust pipe may have some gunk in it. my 07 yamaha 450r had the same prob.