Quick question for your techies...
I was told by the dealer that if I put 4" Rineharts on my other bike, 09 Road King Classic, that I would have to map out the engine.. but if I put the smaller ones on it would be OK.
Everything else is pretty stock.

I thought that with pretty much all slip ons I would be good.. thoughts?

 

No new map necessary unless you change out your A/C to a stage 1, and then you'll probably have to get a tuner of some kind to adjust your AFR.

It's still going to run as hot as it was intended to from the factory.
Pipes is pipes. No big deal..
It will sound better though, and you will be happier, and that's what counts.

 

I put the 4 inch on my 11 SG and it runs good, no popping, and plugs look good.

 

Ditto. No map needed unless BOTH A/C and mufflers are done.

 

I could be wrong but I thought the 4" Rineharts had the same baffle as the smaller Rienharts but the Exterior Pipe it self had a larger look? Again, I could be wrong...

 

Mine sound and work great without a re-map.

 

I put the 4" Rineharts on my 2010 FLHTCU with V&H Power Duals, SEAC and PCV and stock ECM. Used the map for 3.5 Rineharts (M15-011-002) per their techs instructions. Runs sluggish and mpg dropped to 33. I've put a couple of posts on here and even tried contacting FuelMoto; nobody has replied...other then go spend $500 and get a dyno.

 

You are correct...the 3-1/2 qnd 4" RH's have the same baffle. Mapping (if any needed) would be the same for either one>

 

Hes trying to unload his 3.5" Rhinos. They both have 2.25" baffles, you wont need HIS download with either

 

You're right, they are the same