After dealer replaced rear tire on my 07 ultra, headed home. As I accelerate I hear something not right - sounded like an exhaust leak. Assuming it was just me, I made it home to check out the work done and check into noise. Yep - the y pipe had cracked. I checked manual but don't want to risk busting one of the exhaust studs, and can't figure out how you'd torque bottom nut.

FWIW - used JB weld at the crack, to at least be able to get into local indy mechanic and let him deal with busting anything. Of course I'll do it myself if he's not available.

Requesting input on two things; 1. Use the Fullsac option replacing the "y" all together and 2. As a matter of info, how do you torque the bottom nut?

 

I cracked one too. 02' FLHRI. I took it off and had my friend (who is a welder) weld it up. Been fine ever since.

 

After thought..... 1/4 socket with extension or short swivel one

 

hard to get a torque wrenc on everything , swivel and scocket will get it tight but mess up yor readings , to make a long story short just get it tight

 

And don't trust that weld for too long. The motor is constantly trying to re-break it everytime you accelerate.

I rode 250 miles home from Myrtle Beach last year not knowing I had a crack in my Y Pipe, ( bike had just turned 67,000 miles.) It ran fine all the way home in 95* heat.

The next morning however, when I started it up, the rear exhaust valve hung up, ( down) for a split second and the piston tapped the valve.

Fortunately, I located a clean set of take off heads and had the pipe welded.

6 weeks later I bought my new 2 into 1 now on the bike, and discovered that the crack had started to come back!

Weld was just a temporary fix in my case.

(Oh, and a 1/4" swivel socket is perfect for exhaust studs. Snug 'em down, check for leaks, snug 'em a little more and you're done.)

 

I was able to get it ok using a 1/4" drive socket and an 18" extension

 

I would surmise you have a broken front motor mount also, which is probably what caused the y-pipe to crack by allowing the engine to shake too much.

 

Don't feel alone with your broken "y" pipe. There's an extremely high number of "Y" pipes that have cracked and broken ever since the introduction of this design. It's a pi$$ poor design and all of the cracked pipes are proof of that. On several I've seen one pipe extend well into the other causing an obstruction to exhaust flow.
The Fulsac conversion works well and eliminates the "Y" altogether. Some here insist that you're going to lose a bunch of low rpm power but the reality is that you'll likely never notice it if it does. You will notice a better sound and maybe a bit more mid rpm power, and no popping on deceleration.