I had to chase the threads in my pro pipe before the O2's would thread in.

 

Thanks for all the responses. I emailed V&H and verified I received the correct pipes.
Here's what they said about the O2's not fitting.

"This is do to excess plating accumulated on the threads. It is normal procedure to clean the threads with a tap. You can purchase an 18mm by 1.5 thread pitch tap through your local hardware store, or you can take it to your local muffler shop to have the threads cleaned up"

 

That sux. My Samsons came ready to go and the O2's screwed right in.

 

My V&H true duals O2s went in without a problem ... lucky me ... Well at least you know they did a good job plating your pipes!

 

I have the same problem as sapl8.
I'm installing V&H Big Shots Long on my '08 Fatboy. Pain in the *** to be honest. My O2 sensors start to thread then stop before seating. I don't want to force them in. It's the same on both ports.

 

In 2010 or maybe it was 2011, there was a change in 02 sensor size. I though it was just the touring bikes, but not sure. You said the hole in the bike was too small? The change in size was TO a smaller size.....

 

I had no problem with my Samsons either.

Dang, forgot the anti-sieze ...

 

I had this discussion with an engineer ay V&H last fall. I bought a set of double barrel staggereds and when I went to put them on, I discovered that they didn’t mask the bung threads when they plated them.

I told the engineer that I had a set that didn’t get masked and he said they don’t mask any of them any more. I asked him if he was kidding…he said nope! He said that if the O2 sensor is too tight, try chasing the threads with a tap. I said, hows about you guys chasing the threads before you stick it into the box, that’s ridiculous!

Try going to a hardware or auto parts and finding an M18x1.5 tap. That’s about a 35 dollar tap from an industrial or tooling supply, you ain’t going to find one in a hardware store.

I ended up borrowing one from a machine shop customer of mine.