Sled backfiring with new exhaust

[tankeryanker]

Built a new undertunnel exhaust on a 2010 xtx for this year after running an MBRP slip on last year with no problems. Now the sled starts fine but as soon as you start giving it some throttle it will give off a violent pop/backfire. I'm using a cherry bomb type muffler and wondering if anyone else has run into this issue? Would adding more fuel through the factory co settings correct this or will I need to get a programmer of some kind? The sled is otherwise stock and has run problem free until now.

 

[yamaha1973]

programmer i think would be the best way to go... ive seen people mess with co setting with bad results, runs like crap, backfires, bogs, no power

 

[sorenson1610]

Was the sled warmed up before giving it throttle?

 

[tankeryanker]

Yes it was. Had it running on the stand for about 5 minutes before I touched the throttle. The sled only gained about 200rpm before it started to pop

 

[00-NUKE]

Yes it was. Had it running on the stand for about 5 minutes before I touched the throttle. The sled only gained about 200rpm before it started to pop

You'll need a fuel programmer. I would recommend a PC5. They are very easy to install and use.

 

[Supa Dexta]

Try plugging the exhaust (hold rag over it firmly) and see how long it takes to stall it out.

 

[beeze455]

Did you do airbox mods too?

 

[tankeryanker]

No it's completely stock except for the exhaust

 

[shadow44]

How large are the inlets and outlets of the muffler? I'm just guessing that you don't have enough back pressure. Thats one thing you have to consider when using a muffler, you can't go too big or else it's just like running straight pipe...thus it may lean out a bit...by choking it down it will help richen things up.

 

[tankeryanker]

It is a 2 inch inlet/outlet muffler running off of a factory header that has had the outlet cut and turned down on

 

[mach9]

I'm starting to wonder how often the TORS messes up a good plan.
Did you do anything with the throttle cable too?

 

[sonds]

I'm starting to wonder how often the TORS messes up a good plan.
Did you do anything with the throttle cable too?

This is what I was thinking as well.

 

[yamaha1973]

I'm starting to wonder how often the TORS messes up a good plan.
Did you do anything with the throttle cable too?

wouldnt this throw a code?

 

[GHLYAMMY]

yeah when I put mine back together I had a problem with the TORS and it gave me 84 error code, it backfired big time.

 

[radianguy]

I ran my XTX all last season with a cheery bomb set up just like you without any issues. I am guessing you have a different issue, bad gas maybe?