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Put on some new oem base gaskets and got some numbers I like better.

Tried the x of solder, pulled the head to the back, and torqued to the full 15ftlb. All on left cylinder
Only noteable change is the back left and front right almost evened out at .88-.89mm. The back left stayed tight at .74mm and front right was .98mm.
On the note of stock or not, it has a vitos crank, wiseco pistons, a mild port, and cut for 400 headgaskets

I saw your FB post and Ed Toomey was saying 1mm.

He's probably saying that because many are a little sloppy and get it wrong once you start dialing it down closer. It's easy to be too tight on one side and that can cause issues.

Probably the best recommendation is to get the doweled so that you get that variance in orientation removed. Thus avoiding a tight spot that's even tighter than what you have.

Do you mean having the holes widened to fit a dowel in them? Or do you mean centering the heads and drilling them for a small dowel that locks them in? I have tried shifting them different directions and swapping heads with virtually no change in measurement.
With the solder I just used about a 2cm piece in all 4 corners. The head was surfaced but shouldn't have been shortened. I think the machinist either took too much off the top or bottom of my cylinder. From head gasket to base surfaces is 4.024 in, and I read 4.030 is ideal

On the outer circles on my pic is where I measured, basically on 4 corners. Or do you mean front back left and right?
I would honestly rather play it safer with my squish, so if the new base gasket doesnt bring it where it needs to be, I'll have to have the squish band milled.
The heads have been milled flat, can you think of another reason that my squish is tighter at the back? It didn't change almost at all when I swapped heads. I read about a head centering tool and pinning it, but that seems like overkill for mine being a street bike.

Was looking through posts and realized I never came back to this one!
The ebay carrier fixed it! Almost no play on the carrier, and no more random chain tension.
I remember when I first got this bike running and riding, I was messing with something and found the sprocket loose! And that was with lock tabs secured, so theres no telling how that went down.

So with the stock chamber shape/cc, am I just worrying about contact between piston and head at rpm?

So I guess this head has enough room in stock form to not be a compression/detonation problem?
The only other thing is I was told to torque at half value for the measurement.
For a bit of comfort and playing it safe I may run the thicker oe gaskets.
I got my 400 headgaskets from hvc, and they don't have the crimp/crush lip on them. They measure .5mm so they should be plenty thick

shouldn't. 

each motor is different, but i run tzr at .8-.85 mm for a data point.

is that on pump gas as well?

Wow, thats good to hear. I'm kind of shocked though, I thought this was tight.the local 2 stroke guy is saying he likes to stay 1mm or over for pump gas, but I came for more opinions
Also, does it matter that I am running wiseco/forged pistons?

Hello, so I am rebuilding my 73 RD350, and I had the cylinders cut for the 400 headgaskets. I took a pic of the measurements and where they were at. From what I know I want 1mm for the premium pump gas I plan on using.
I used an athena gasket set, so I believe I can bring the cylinders up a hair with OE base gaskets.
I figure I should try this first, but do you guys think I will end up needing to cut/recut the chamber?
The inner circles are the first measurement, then a second measurement on the outer circles.

That definitely scares me a bit to tighten that down with an impact on the crank 
But thats good, I'll pull them back off and give a bit of loctite.
And it sounds like I was just a bit heavy on the 7mm bolt, I did 12.5 ft lb

Yikes! Pays to check a bike over now and then

I am on the re-assembly side of a full rebuild on my 73 RD350 motor, and had a couple torque spec questions. For the clutch nut and the primary gear nut, my old clymer manual says 29-32 ftlbs. The only other thing on here I could find was someone saying it should be 50. Should I just stick with the manual?
I also couldn't find a spec for the long bolt for the flywheel. Its 7mm, and the manual says 90 inlb for 6mm, and 180 for 8mm, so I just put it at 150 in lb. Any issue or insight on that?

I haven't done many stud replacements, but I would just install them with nothing on them and snug them up. I do see the end with the longer amount of thread goes into the cases. Getting the old ones out can be a chore.

Yeah. I got all but one out. The last one was the worst. None of my tricks worked. It got handed to the machinist.

when i replace them i chase the threads with a cleaning tap then blow out the holes clear. i used a bit of blue Loctite reinstalling. just seat them but if you need a torque spec its 12-15 ft lbs. its set by thread pitch and material etc. (typically)

I have chased the threads and cleared them. The loctite is likely how I will do it.

Most are interference fit from factory.
Meaning stay tight to the case.

Like the threads taper down? I have never heard this.

Did a search and couldn't find a post on this.
I haven't ever had to replace head studs before, and since mine are crusty I decided to replace the head studs, and some of the ones that hold the cases together.
I know the flat end of the stud goes in the hole, with the domed end sticking out.
Is there a torque spec to this or is it just good and snug? My old clymer manual doesn't even talk about replacing the studs.
Some say loctite, some say antiseize. What are the opinions on that?
Bike is a 73 RD350.