Originally Posted by shepdog
why do you think it needs a top end?? ...
+1 on this question. Unless there are specific things indicating the top end needs to be re-done there are other things to take care of first. Here is a thread on how to get a bike running that has sat unused for a while ...
Tips For De-hibernating Your IronHead
If it has been smoking as shepdog
says the top end may need attention. Once you get it running and warmed up you can do static compression and leak-down tests. These will help determine what top end work may be needed ...
Cylinder Compression And Leakage Tests For Your Ironhead
If it does need top end work you will need to find a machine shop that is familiar with ironhead engines and has done this work before. They will all tell you that they are expert and can do the work but trust this: many will screw up your engine. It will possibly be better to spend some $s shipping your parts to a known good old-time shop than using a local guy.
The machine shop will need to measure the cylinders to see if and how much honing or boring may be required, and then have the pistons in hand before boring the cylinders.
10:1 Wiseco pistons are a good choice - i have them in my '78. However, they do require some extra tuning. Higher compression requires higher octane fuel and around here the best i can get is 91. I got it running very well by installing an electronic ignition, a VOES, and by retarding the ignition timing from the static setting.
It may be better to stay with stock compression pistons, 9:1 i believe.
Anyway, first get it running!
No hurry! If it runs ok, perfect is not required, run it for a year, take care of the dozens of small issues
that you will find [electrical, brakes, carb, tires, chain, etc, etc, etc], and leave the top end until next year.