Cylinder Base Lapping Tool
 

I see that Trock used to make one,


http://www.vtwinmfg.com/webapp/wcs/s...102_3295352_-1


is someone else still making one for sale?


I can't seem to find it they are,


Thanks.

Does it have to be a lapping tool?

For a lot less than $115, you could just stick them in a lathe with a large enough live center to hold the spigot end of the cylinder.

I'm prone to using thick float glass as a cheap alternative to an (engineering) flat surface when it comes to leveling things, like covers. You make me wonder whether it would not be possible to make one out of a piece of glass and have someone cut or drill a 3.5xx" hole in it, e.g. a kitchen outfitters that work in marble/granite if your glass shop cannot? The Trock ring measures about 3.685" ID.

But the lathe option would be my first call. Hell of a lot easier way to remove all the paper base gasket too.

There are always work arounds depending on what it local to you.

when Mr trock was alive he made them but that is over - it did not work that well anyway - cutting the base is what we do

I had one made out of granite from a granite and marble shop. Friend owed me a favor.

My thought is some valve lapping compound, or even sandpaper tacked down and lots of twisting, lifting, rotating, etc.

However, I have not used mine yet. Most marble and granite shops have a small piece that they cant really do anything with. The only real labor would be cutting the hole.

Probably won't last as long as the trock, but for the guy at home doing his own wrenching on his own bike only, how many times do you really need to use it? YD

Lapping the base may get it flat, but does not ensue that the base is perpendicular to the cylinder bore.

That is why you trust a good Harley machinist to true the base of the cylinder using a lathe.

Lapping the base may get it flat, but does not ensue that the base is perpendicular to the cylinder bore ... B I N G O !!

Dan has it!
We use a dedicated set of aluminum custom soft jaws, approx. 3" long, that has been turned to a 3.500" radius to grab the bore I.D.
We then indicate/insure the bore is running true(.001") with a Starrett universal test indicator, and then support the spigot via a bull-nose center.
We then, touch off on the face of the UN-MACHINED, AS-CAST, Evo cylinder base, and gently skim as needed to establish a precision, fully machined surface, that is dead-balls perpendicular to the bore.
At that point, if in fact boring is needed, we then mount the cylinder on the precision machined base in another fixture, indicate once again, lock it, and bore.
This process works VERY well. :)
Scott

I'll bet it does, what does that sort of machine service run?

i have the Trock lapping tool... i used it a few times without any issues

Canada is a big place, however Scott is in north NY state, so may not be so far away......