There's a technique to kick starting big singles. First, as Chucky said, no throttle. Do the kicking bit with the throttle shut.

For the next bit I'm assuming you've got the timing right and that it's not stuck / defaulted to full advance. The timing for starting should be around 5-10 degrees BTDC. If it isn't, for whatever reason, it will kick back. It's unusual for modern(ish) Jap stuff to have a timing problem but for the sake of your leg it's worth checking.

Next you need to get the piston in the right place for starting - slowly push the kickstarter down until you can feel it come up on the compression stroke. Now pull in the compression release and ease the piston just past the top of its stroke (you can feel it move). Release everything, let the kickstart come back to the top and come down on it with your whole weight. You need to get the piston moving as quickly as you can - a wimpy kick won't work. Keep the throttle shut!

The idea behind getting the piston just past TDC before kicking is that it then has two complete revolutions to get some speed / momentum going before the firing stroke (and at the same time the kickstart reaches the bottom of its stroke and disengages from the engine, so saving your leg). Half strength kicking or starting with the piston in the wrong place are the main causes of kickback.

If it doesn't start within 2-3 kicks you've probably flooded it. Switch off ignition, switch off fuel and choke, open throttle fully with compression release pulled in and kick the engine over 3-4 times to remove excess fuel. Then switch everything back on and start again.

On the xt 500 they had a decompression lever on the handle bar you pulled in to get the stroke to top dead centre, on the xt600 they didn't

The method I use relies on the automatic decompression properly adjusted and working.

Slowly kick until you hear a loud (rather loud) click, stop, allow kicker to return to top then with throttle closed kick very hard and fast. Use choke if engine is cold. Once you hear it fire add a little throttle to keep it running.

The click you hear is the decompression lever, you can see it move when it clicks.

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'84 XT600 is now bored to 2nd oversize and new OEM pistons and rings installed. No more smoking.

Hi guys Eddie here again. Thanks so much for your time and kindness in replying to my requests for help. I had a 1984 XL600R that had tough to kick lever compression but it never ever came back to almost literally break my foot in the instep. I don't remember hearing a "click" when I try finding top dead center with the kick start lever. Maybe it's a combination of the auto decompression cable and a defaulted stator?
I have to drop the bike off to a private all around mechanic who is the son of a friend. I just want to know what possible things could be causing this so I can tell him what you guys suggested and what parts to buy from ebay.
Lastly does anyone know if a stator assembly from a 1983 xt600 will work on the 84 model?
I'm going to try all the things you guys are suggesting. One post said they replaced the stator assembly and it corrected the problem. Is there a way to check if it's in spec as far as ohm. I'm a little confused how it all works. Any to make matters worse the local yamaha dealers won't even take it in as a repair job because it's so old they say they don't want to get involved. Thanks everyone for much needed advice. Let me know all the steps I should cover. I'll check the decompression cable too.
Eddie

In the dealership unless it's got a plug so they can plug a diagnostics unit in they are not sure how to diagnose a problem,
The machanics are still in there nappies, I've got bikes older than them

Hi Eddie,

XT 600s don't kick back. Spark timing must be wrong. We had that here after a stator rebuild.
There are 2 pick-ups for timing, one for slow and one for fast. 3 wires come from pick-up: green is common, white with green and white with red go to CDI.
Can't find the note i made to self which is which. Quite possible to get those mixed up, try swopping the 2 white with green/red trace.

Best.
p

Throttle needs to be kept shut while starting
Even if the throttle is fully closed the throttle stop screw on the carb may be screwed in a bit to much, this has the same effect as opening the throttle.
I would try unscrewing the throttle stop.