% %Hi Stuart, Here's the F&G OIF sump gaskets. I believe F&G has these custom made for them??
Triumph Oil In Frame Sump filter gasket pair aluminum core – Franz and Grubb Engine (fagengine.com)
The rubber is soft, but not foam. .053 thick. I don't how thick the aluminum is. I peel & measure it next oil change.
The holes were punched 5/16. Not 5/16 clearance. Any of the gaskets that come punched 5/16 bind on my studs & I have noticed same on all the OIF sumps that I removed. Factory was not so precise drilling stud holes. Paper gaskets I'd nibble the holes larger with pliers type leather punch. On these I used my old sump plate as a drilling cover as you cannot drill sheet metal without a cover or it will buckle. I drilled the holes to 11/32 to match diameter of holes on the original factory cover.
Gaskets must never buckle or bind on fasteners or they will seep or flat out leak.
Previously I'd been using Bonneville Shop gaskets which I feel are high quality, but as I said without sealant all paper gaskets no matter brand/seller seeped.
The BS gasket holes are clearanced to about 11/32 which allows gasket to lay flat nicely. The BS gaskets sell for $7.51 pair, free shipping, no tax. Any direct sales from shop in California I must pay tax. The F&G gaskets sell for &10.29 pair + 9% tax + shipping. Total cost is obviously a fair amount higher for the F&G gasket. For not having to deal with sealant & no leaks, it's worth the higher cost to me. If other owners are satisfied with paper, that's good for them.
I Loctited 272 the studs some years ago when I attempted to flatten frame bottom. The studs don't enter the oil space anyway. I didn't put any sealant on studs, washers, nuts when installing these gaskets.
Jury is still out. I installed them 9/2/23. Covered 391 miles. Weather has been under 80f. What will 110f do?? My experience is paper without sealant would have already been leaking on this bike. So it's looking very promissing.
If you zoom in on the installed photo you see what looks like maybe sealant peeking out. That's Staylube blue waterproof wheel bearing grease I smeared on gasket.
Here's the photos showing details.
Don