Submitted by: springer_ (V Twin Forum) & http://www.bigboyzcycles.com/

Something that can be easily overlooked when building a performance V-twin, the exhaust gaskets. The stock exhaust gaskets have a lot of "crush" in them. They tend to crush down and block the exhaust port. After spending hundreds or even thousands on the heads, installing the stock exhaust gaskets can take away a lot of the performance gain.

We ship a set of SE performance exhaust gaskets (or equivalent) with the heads to make sure that the right ones are used.
HD part# 17048-98

I took a picture of a stock exhaust gasket used in a ported head.

The part of the gasket between the Yellow line and the Blue line is the "shelf" where the gasket sits.

The part of the gasket between the Yellow line and the Red line overlaps into the port, partially blocking it. You can see the clearly defined line of Carbon from the exhaust gasses. Also note how irregular the inside of the gasket is. That is the part that gets "Crushed" into the port.




This is a picture of a performance exhaust gasket that was removed from a ported head also. It is a good comparison to the stock exhaust gaskets. It is easy to see that there is no carbon line like the stock gasket. It is a good representation of how little it blocks the port compared to the stock gasket.

 

What about these Cometic copper and steel gaskets on the picture attached ? Any comments on which is better?



Thanks

Mauricio