So I have my brothers 04 rx8 In my garage for a new clutch and flywheel. And come to find out the ring gear isn't attached to the flywheel. I'm at a loss as to how to replace the flywheel now that I can't use a ring gear lock to bind the motor, any suggestions would be helpful. I've been crusing the forums here for a few days and can't find anything on the topic of binding a rotory motor. Can it be done without damage to the motor?

 

How did the ring gear come off?
You could try locking the engine via the front 19mm bolt but it's not the best solution as it may stress the assembly more than it's needed.

If everything else fails... spot weld the ring on the old flywheel and call it a day, you're replacing it anyway

 

unless u did something seriously wrong there is no way the ring gear to fall off. they are heat fit if it comes off it should chew ur flywheel, clutch, probably ur tranny and ur leg when doing 7k rpm.

if i were u i will replace them, just to be safe

at this point the easiest way is to use impact to get the big 54mm nut off, no other way easier than this, factory FW have Loctitie on so u can heat the big nut up with a propane torch for a minute, then bang it with an impact, it will come right off.

 

Big assed impact

 

My brother destroyed his clutch and kept trying to start it, I assume that's how it came off. All I know is when I dropped the tranny it wasn't attached, it just spun on the flywheel

 

I've had to work on a similar issue on a local kid's RX8.
He was having issues with the clutch slipping and couldn't wait for the weekend for me to look at it.
So he kept driving it and caused more problems.

Here is what the clutch disc looked like (his is obviously the one on the left):


When I removed his starter, a large clump of disc material fell onto my lap.
But once the transmission was removed, I too found the ring gear popped-off/came loose:


I was able to hold the ring gear (with a stopper), but the rest of the flywheel still spun.
Eventually, the ring gear just came off.
Like others mentioned above, use an impact to remove the flywheel nut.

 

sad, people really got issues, they know there is a problem, but they always feel "lucky" about it and like "hey, it's not that big of a deal, it's already broken how bad can it be?"

well, there is no cure for idiocy I guess.

 

I recently suffered the same, ring gear dropped off my 2009 RX8 (series 2), car is at 120,000km. Luckily this happened at low speeds in the carpark, phew.