Hi I have a mega .21 motor and I can feel the rod ends are going bad. What will happen if I keep using it? Can I just keep using it until it fails and then replace?

Thanks

you dont want the rod to fail at 30,000 RPM !
replace the rod and the piston pin before it goes bang.

if you wait till it fails, then you will be replacing a complete motor, not the rod.

In very few cases, mostly when it breaks at low RPMs, you can rebuild a broken conrod engine. Usually it breaks the engine block, other times it damages the piston beyond repair and usually damages the sleeve in the process.

If you feel the conrod has play or already has alot of fuel through it. Change it, $30-$40 are a whole lot cheaper than $300+.