Tranny oil type

I'm pretty sure you want to use gear oil in the crankcase of a two-stroke,(like 80wt Bel Ray).
Standard "car weight" motor oils are 4 stroke, designed to lube the crank & cylinders. your '03 RM has the cylinders lubed by the pre-mix...
A motorcycle specific crankcase lube is the best bet; lots of differing opinions on the wet-clutch aspect.

You can run Motor Oil in the Tranny or we run Automatic Transmission Oil in ours and we change it alot. We also run Lucas 2 Stroke Oil at 40:1. We run our Banshee and Yamaha Dirt Bikes on that also. Hope this helps.

The standard mix is 4 ounces of two stroke engine oil to one gallon of gas. Do not use standard motor oil. Only use two stroke engine oil.

The engine doesn't use oil,the only oil it gets is from the 2 cycle oil mix in the gas,the transmission uses 85\90 transmission oil such as bel-ray or others. I would NOT reccomend running 10\40 in the trans...

sounds to me like shes nipped up in the bore possibly to a broken ring or lack of oil or coolant unfortunately the damage is done you will have to remove the cylinder head & barrell to determine how much check the oil pump for blockage & function was there adequate oil in the tank alsowas the coolant resevior full at the least it will need a set of rings & the cylinder honed at worst big end bearings if the bottom ends locked up this involves splitting the cases so for your sake I hope my initial diagnoses is corrrect

I am pretty sure Suzuki recommends 10W30. I agree with you - if everything else is good then I would try a different oil.

HTE RM'S ARE GREAT BIKES CHECK WITH A DEALER, I THINK THEY WILL TELL YOU TO USE A SYNTHETIC OIL BUT THE MIX IS 32-1

Bel Ray Gear saver for two strokes is good stuff. Available at any bike dealer. You can also use regular motor oil (10-40w) but I've had great luck with the Bel ray. It's synthetic and made for that application.

Use 10w40 motor oil in the gear box. Don't use any synthetic oils, oil marked "EC", or oil with "special" additives. Stick with the major brands; Pennzoil, Quaker State, Mobil or Shell.

Use TWO STROKE ENGINE OIL in the pump. If not using an automatic oil pump, then mix the gas and oil 32 to 1. That equals 4 ounces of TWO STROKE ENGINE OIL to one gallon of gas. NEVER use motor oil in the gas. Only two stroke engine oil.

Please top rate this answer. Thanks!

could be too much 2 stroke oil in your mix or worse case, your piston rings are going.