[garandguy]

I'm looking for some quick info about the 500t headers. The 500 I just purchased has a hacked up makeshift exhaust on it and I want to build new but I don't know what the header diameter should be. Any info would be awesome.

 

[Lefty]

1 3/8" is available. I went 1 1/2" electrical conduit bends once and it they were too big for a street 450. It was a noticeable low and mid range loss in power. Some research will confirm it. Cb500? I'd guess would be the same. You'll see 1 1/2" common on race bikes and sometimes bigger on full bore engines, but that's high rpm. If it were me for a stocker, I'd go 1 3/8". I think that's actually a little bigger than stock, but 1 1/4" is a little too small.

 

[tbpmusic]

1 3/8" is available. I went 1 1/2" electrical conduit bends once and it they were too big for a street 450. It was a noticeable low and mid range loss in power. Some research will confirm it. Cb500? I'd guess would be the same. You'll see 1 1/2" common on race bikes and sometimes bigger on full bore engines, but that's high rpm. If it were me for a stocker, I'd go 1 3/8". I think that's actually a little bigger than stock, but 1 1/4" is a little too small.

I'm fairly certain that the OD of 450/500T is 1-3/4"........not sure what the ID is, never checked it).

 

[Lefty]

They are double walled down to a certain point. I've never split one so I'm not sure how much they're mashed down through the bend. I doubt very much though.

 

[76TWIN]

CB500T Header pipe OD is 1-9/16" (1.5625") or 3.96875 cm (39.6875 mm) I just measured it with my caliper

1-1/2" is about as close as you're going to find.

Keep in mind that the stock header pipes are double walled so the ID will be much smaller.

 

[Zeek]

I went with 38mm OD pipe on my 450.

 

[garandguy]

Thank you all for the your input. I think 1.5" is going to be perfect, plus I get a lot more options for different bends. I will be posting pics of the exhaust build as it comes together.