Exhaust Washer Orientation

I'm putting exhaust nuts for an 850 on my 750 and safety wiring them as suggested by Old Britts. I also ordered the seals they recommended. They have a flat side and a convex side. Does anyone know which way around they go, as I don't have an example to go on? Also, the seals don't fit exactly like I expected. I imagined their diameter would be larger than the outside diameter of the threads on the exhaust nuts but smaller than the fins so they would fit flush against the outside of the head. Instead, the diameter is similar to the threaded portion itself and would therefore fit inside the head and against the inside edge of the nut? Is that right? :?:

Yes they do go inside.

OK, good deal. which way do they go in? Convex or flat side towards the head?

I have always put the flat side towards the head, Not sure if others do it the other way but it has always worked for me.

All right! Thx for the info!

On some exhaust headers (most, but not all), the fluted end of the pipe that inserts into the threaded exhaust hole has a concave shape that accepts the convex seal. also, you ought to have a split collet that typically breaks into two parts; you need to slip those on just before the nut to form a labyrinth seal.

When I have pipes that have a flat lip on the end, I use copper crush washers; if everything doesn't quite snug up with just one, I use two.

I likr the locktab washers to keep the finned locking nuts in place.

The 850 crossover style headpipes had a split collet to hold the pipes in place, and the threadded part was a lot shorter. You will probably find that the 850 exhaust collars are too short for 750 pipes with the flat/rounded crush washers. My solution for that is to use steel crush washers for a Suzuki GS-750, their part number 14181-01D00. I think the idea came from an old Norton Tech Notes publication.