My experience is kick back is 90% timing and maybe 10% "technique".  For example, stroking away at the kick starter like a madman on any bike can result in a kick back.  Light flywheel bikes and a "weak" kick through are more likely to kick back.  A flywheel weight on a 360/400 would make them easier to start.  

I had a stock DT400D...  (1977 DT400MX for our overseas friends)  The stock CDI ignition retarded the timing for starting and it started easily with no kick back. 

I converted it to the 1977 DT250D points system and set the timing at 0.100" BTDC...  slightly retarded from stock.  Same thing.  Started easy. 

(Years ago I read some articles that said today's cleaner fuel have a faster burn rate and old two strokes can benefit from retarding the timing slightly.  I did some testing with the DT400 and there was no measurable performance difference with the timing slightly retarded.)

Sorry i was posting on the previous page but came up here.
Cable operated compression release like in the link won't help starting, only stopping. Unless i'm misunderstanding what's being expected from it.
I've read people like those chainsaw type that reset when the motor starts. I have one on my chainsaw i didn't know was there & been struggling to start it for a long time haha until oneday i saw the button--Doh!! what's that thing for. Think on chainsaws they just open a hole higher up than exhaust port & let a bit of comp out.
In the DT400 i don't think they have a spare plug hole? to fit one in.
Mind you the original decomp if not blocked should soften it up good.

They should help with starting - in fact, my mechanic said that, if opened too far, not enough compression to start the bike! Some folks use a Harley decompression release valve, but I have a feeling that is M10 thread and might need a converter to M14.

You're right, Morley, DT400s don't have the extra plug hole.

All good & i'll be very interested in the outcome.

My rt1mx is really not fun to try. After the rt2mx head, I have faith it will break anyone's foot or leg. I can barely kick it through with the ignition off, and im not a small dude. It has no compression release, and no timing retard. I'm honestly puzzled at how much trouble a dt400 gives, with both the timing retard and compression release functional.

My rt2 rat thing has an rt2mx top end & points ignition no decomp but starts easily with a full follow through kick & wearing my mx boot. It 'would' kick back if I didn't do it right, but the higher exhaust port might soften any kickback although higher compression head probably wipes that theory.

When I had the rt2mx top end complete, it was very easy to kick start, similiar to how you mentioned yours was, rt325.  The exhaust port closes significantly later on that cylinder.

Well, up in northern Mn, next week might be time to drag my old RT2 grey mule out of the shed… I do live on a hill, ooh I soo lucky…
Sneezles61

My relatives that live by Bemidji say there is a lack of snow up there? What's it look like where your at, sneezles?

No snow all winter… trees are budding, well, poplars any ways.. Think of it as it was just a cold fall…
Sneezles61