Shovelhead Guide and Seat Service

[dukekleman]

I had a shop call this week. They were looking for repair options on a set of shovel cylinder heads they were rebuilding on a customers 74" shovelhead motor.

I can say out of the hundreds of these I've done over the years, it's been awhile since I've seen such worn out rocker arms, shaft's, valves, guides and seats. They were really bad!

We talked about valve seat replacement or installing oversized valves. The shop and owner of the motorcycle decided on going the route of oversized valves.

New oversized valve guides were measured up for the guide bores, pressed in place and honed to the required clearances.
IMG_20250905_100621099.jpg
Note how sunk the valve seats are and shrouded
the valve were in the photo above.

IMG_20250905_152908619.jpg
This image shows the new valve seat angles plus a radius radius and unshrouded chamber. Valve seat margins are lapped in shown in the photo as well.

IMG_20250905_152852939_HDR.jpg
Intake valve with margins set on the left and exhaust margins set shown on the right.

Valve stem protrusion heights were all set to the exact height measured with my dial indicator and custom tooling . Meeting factory specifications.

I normally would have installed all new seats, however the owner didn't want to invest that much into the heads at his age and miles he will ride this secondary motorcycle of his.

I'll top them off with a set viton valve seals to control combustion chamber oil contamination and he will get many, many miles out of these.

I hope this helps make decisions on options available for others that may encounter similar scenarios...

Duke Kleman

[micmac]

Thanks for sharing Duke. I always loved my shovels. I bought one new in 1982 80 CI never had a problem.

[dukekleman]

Pete,

While I've never bought one brand new, I bought my first Harley Davidson my senior year in Highschool.
It's a 1971 FLH. It was the local HD dealership personal motorcycle. I still have it today. I've put just under 150,000 miles on it and it's still my favorite.
My kids grew up riding on it and drive it now themselves. They think it's a great motorcycle!
So I agree with you, I love my shovelheads and have a few of them in my fleet.

Duke Kleman

[joe fxs fxr]

My 79 FXS is my favorite bike to ride, it looks, sounds and feels right to me.