Digital measuring caliper is about $30 from Home Depot. Micrometers from HarborFreight are about $30 too.
Pistons are probably aftermarket. I use Asian pistons for car engines all the time.

 

Scott - the measurement here is 3.527" - so I presume that's a piston for a .030" overbore. Measurement at the top of the piston is 3.497"

Off to the machinist tomorrow morning, so we'll see whether it can be honed to 030 or needs bored to 040.

What pistons would you all recommend? Keith Black seem to be well thought of and a decent price. S&S seem damned expensive.

This motor isn't going to be high performance. More a lower and middle range bar hopper. I'll add a new cam, and up the compression a bit but I understand there's not much you can do to the stock shovel heads as the valve pockets are large already.

 

I bought KBs for my recent top end rebuild. I'll not buy 'em again.

The motor runs well, but is noisy until it warms up. Noisier than it was when it had the stockers with 50K miles on 'em. The machine shop may have set them up looser than they needed to be. I shoulda checked, as I have the stuff to do that, but I didn't. I trusted the shop. Even so, if they had just a tiny bit more clearance than recommended, I woulda run 'em anyway.

In hindsight, I shoulda bought something else. Wiseco and SE came highly recommended. That may not be an option for an older platform such as yours though.

 

Thanks Mike,

Looks like Wiseco sell an 0.030 and 0.04 piston kit for shovels in 7.1:1, 8.5:1 and 9.5:1 configurations for shovels for reasonable money.

Given Scott's recommendation for the Andrews #2 grind cam at 8:5:1 to 9.0:1, the 8.5:1 set might well be a good option.

 

Under the suspicion, that you have a plus .030", 80" engine.
Scott

 

Yep - that's what we decided it was. The good news is the barrels are pretty good and look as if all they need is honing. Final decision to be made when the work starts.

We also discussed the Andrews #2 cam among others, and concluded that it looks like an excellent choice for the motor given my goals. We'll set compression at 8.5, probably using the Wiseco piston set I mentioned above.

No definite decisions on the work yet as the builder wants to inspect the bottom end (which is still in the bike), but it looks like we will probably replace the rockers and shafts at the top end, new valves, springs etc..

Crank will be trued, all new bearings, bushes and gaskets throughout, probably a new S&S oil pump. I might replace the rods while we are in there as well.

Cases, barrels, heads, rocker covers will all get vapour blasted and the barrels and lifter blocks will get ceramic coated black. All new stainless hardware throughout.

So basically a total engine rebuild. I'm looking forward to it!

 

deleted.....head up butt, doh!!!

 

IIRC shovel engines had pistons available up to +.080. That may be a symptom of engine wear back in the day! I heard in the mid-70s that the US Police rebuilt their Harley engines many times over before retiring them.