Got the two brothers slip on and dynojets but I noticed about 4000-5000 feet i get the popping backfire. Not alot. But getting back down to about 1500 feet it goes away. Any suggestions? Thank you!!!

 

What jet are you running and what is your air screw at?

 

You can get ride of some of the popping with the air screw. With elevation changes that big you should have an aftermarket fuel screw in there so you can just turn it in or out by hand as your elevation changes. Whats happening is the higher you go the thinner the air is and your ratio(fuel to air) changes. To get rid of some of the popping you can dial in more fuel or less fuel as needed to get your ratio closer to where the bike won't pop like that.

 

dont bother changing anything. it works fine, whats some back firing among friends?

 

ah yes, sorry, my main is 128 and I have the adjustable screw at 2.5 turns out. Yes I was thinking that i might have to adjust as riding. Thanks.

 

I just fitted a Two Bros Slip on to my 09 KLXs 250. Love it. Power increase is great however getting some back firing when I throttle off. Normal or not???????
What do you think.

 

ACOLE - I can say for sure that it happens quite a bit. Not sure if it's normal but I've had a bit of decel popping since I started opening up the air/fuel system. It's not bad now but you have to keep messing with stuff to completely get rid of it.

 

I get it as well with the BB pumper carb and 2bros slip on it is not that big of deal just on hard decel

 

Thanks Army Copter & Ramjet. I don't mind it so much in fact it sounds kinda cool. Is it doing any damage to exhaust valves etc???

 

Different issue but I tried the the KDX high flow snorkel which fits straight into the stock airbox. Thought it might compliment the Two Bros Muffler nicely but all it did was make the bike surge when trying to cruise on the highway. Definitely quick under acceleration. I guess re- jetting to make this work properly. What you think??