Exhaust temperature question

[WINDYCITYJOHN400]

I disagree with this statement! I have tuned a shit load of bikes as I know you have but there is no way you can make a statement across the board saying every pipe out there wants at least a 27.5 pilot. I have found more than one bike that ran better with a stock pilot than it did with a bigger one. It really depends on the bike. 

 

Well let me put it this way……WAY too many Banshee owners only tune main jets. Or they get a bike and figure "Since it is running, it must be dialed in from the last owner."

 

My point is, once you remove an air box or a lid, or put pipes on a bike MOST of them need to go straight to 27.5 pilots. Now it's true that a built motor can end up wanting so much air that the signal strength pulls a ton of fuel up a jet and you end up needing to go DOWN on jets to get the tune right.

But in general I believe that (In the interest of providing a good starting point) it's better to assume that once modded….the 27.5 or even a 30 needs to be in place until proven otherwise.

 

I have YET to see a simple bolt on pipe mod done that DIDN'T need at least a 27.5 pilot. But that doesn't mean that once more mods were done that a different pilot didn't end up being needed.

 

YOU ARE CORRECT. I cannot just make a blanket statement like that.         But I still will.    Only because SO MANY people are running too small of a pilot. Plus being jetted rich is way better in the long run for a novice tuner than to be lean.

After all…….If you're well versed at tuning…..you aren't going to need to listen to my input anyway right? 

 

But for anyone else reading who has pipes and a stock pilot…..or DON'T KNOW what their pilot is…….My advice is get at least some 27.5's in there unless you're certain WHY the 25's are best.

[camatv]

i have also removed 27.5's and 30's from bikes because they were way to rich at idle and right off idle.  a lot of motors around here like the 25's  after the carbs are synched dead on  and th emain is really close AND the rest of the bike is solid..  the idle mixture screw can tell you if your slow is to big or to small really quickly  now your area where you ride it may be different.  really  you just need to tune to what the motor wants  AFTER everything else is verified to be ok.  more often than not this is the case  other problems that seem like jetting issues.  the best tool i ever built was a leak down tester.  i should have made one years and years ago.