My bike has been dyno tuned because of the 255 cams that I put in a few years back. I've ordered a set of true duals to replace the factory head pipes. Any idea what this will do to my existing tune? Will I still be able to ride the bike, or will this significantly change the way the bike runs and require another dyno tune?

Thanks for the help!

 

Which tuning device did you use when you had the bike first Dyno'd? I'm guessing that you've also changed out the air cleaner for a less restrictive model? You're going to have to re-tune the motor because you are dramatically changing the way the air will enter and exit the engine. The bike "may" run very lean until a new map or a new Dyno tune is worked up.

 

Yes it'll need tuned again

 

That's what I expected. Any ideas if it will be safe to ride before retuning? I may have to travel a few hours to find a good tuner.

Chad, you helped me a great deal a few years ago when I was trying to use smart tune to get the bike dialed in with the 255 cams. I wish you were a little closer!

 

I've got the screaming eagle super tuner and the stage 1 air filter.

 

It's really hard saying how much change the new exhaust will have in the way the bike breathes. Can you do a couple of 20 minute smarttune runs to get it closes before your trip to dyno?

 

Update: true duals installed with Rinehart slip ons. The bike sounds and runs fantastic. Power delivery is super smooth; the bike is definitely breathing easier. I really don't feel like I've lost much on the bottom end.

I really can't see spending 400 bucks on another tune with the bike running as good as it is. Any thoughts?

 

Ok, I've picked up an honest 4 mpg since installing the true duals and Rinehart slip ons. I'd really like to hold off on a dyno tune because I might do some engine work this winter. What do I need to look for to know if the motor is running lean enough to do damage?

 

There is no simple answer to if you risk damage. The safe thing to do is get your bike dyno-tuned, as already suggested. When I swapped over from TDs to a 2-into-1 I rode for about four hours to my preferred tuner, to retune my bike. It was well worth it and it flew back home! Yours may well do the same. If you're planning on further changes, then dyno again after them. But it's your bike......