Hey Guys I am stationed in Afghanistan and like so many I have very few things to kill time. I got a MRX5 and the RB .21 to run around the helo pad with. The only problem is I can't even get the thing running to start the break-in procedure. I got a hold of a heat dryer and tryed heating it up and she only cranked one time and lasted maybe 2 seconds if I am lucky. She always locks up and than I have to use pliers on the flywheel to bring her back the other way to free up. That pinch zone is a real pain and I am not enjoying it. My bump box is pretty useless once she hits that pinch point. Is there anyhing else I can do to make my life easy so I can actually hear my engine run and start breaking her in?

Start to turn in the idle that much so it is just not locking the carburator.

It must give enough idle to keep the engine running.

Do you have a temp gun to see if the engine is getting hot enough with the hair dryer? When I switched my starter box over to a 4 cell lipo it now sounds like it will start almoast anything.

Yeah I had a temp gun which was reading from 135-143. What I have been doing is as soon as the motor locks up I take a pair of pliers and tunr the motor opposite the direction of normal rotation at the pinch point so I have a full rotation till I hit the pinch point again...... and the motor locks up and the bump boxs bogs out and is just eating up my wheel. Do I need to get her hotter than this or what? I have the mugen bump box with two 6 cell batteries (7.2v x 2). Its frustrating to say the least

RB engines are definitely going to give you a massive headache in the beginning - I had the same problem with you.
What you have to do is get it hot like you have been doing, then once it has enough heat inside the engine, squirt a little bit of fuel down the throat of the carb, keep the glow plug lighter on for a few seconds before cranking it over and as soon as you hear it starting, just blip the throttle so that it revs a little (not full throttle blips) and try and set your idle screw to the point where the engine won't lock-up on you. If you can hear it start to pinch up - trust me, with an RB, even a little .12, you can hear it when it starts to pinch up - just give it a little rev to pick up the RPMs.
I would use Josh Cyrul's WOT method of breaking in this engine, so that you don't really have to worry about it idling and looking/listening if the engine is about to lock up again. Just a thought.

heat up the engine like a M.F. Then when you push down on the car, rev the throttle a fair amount (like 1/3 throttle blips) push down on the box, and once it is turning the engine over keep it down and blip the throttle by 1/3's it should start.

if this doesn't work, do the above but loosen the glow plug just a fraction, keep the glow plug warmer on the plug and do the above process.

When I was breaking in my T-10 I took it up to 170 F.. Try taking it up to at least 180 degrees F. and should be loose enough to start no problem.

I had hotter, and it still tried to pinch up on me

Thanks for all the info guys. I got her running today but ur right she still pinched on me a few times. I got her up to 180 before she started up but dont let her drop below 160 or u can hang it up. Seriously thanks guys.

That's what we're all here for!

I got mine few days back. And doing break in today.
The needles setting u get from factory for idle and an main needles is wrong.
Idle should be around 3.5-4 turn out. Main needles is around 4.5 turn out for break in.
And get a heat gun which able to get the engine up to 90 degree Celsius atleast to start your engine. I burned 2 start motor on my start box before I get that temp up for break in.
And I run 6 tank idle on stand. Still that engine is very tight and need heat gun to get temp up to 80-90 Celsius to start the engine. And I run it rich for 4 tank only 1/2-3/4 throttle. Temp around 80-90 Celsius after 4 tank.
And the end result still very tight on the piston so I assume this engine is a wild beast need times to tame it.
And hopefully after 1 gallon this beast is tamed.

So basically u need to get the engine up to 90 degree Celsius just to start it. And make it rich but able to stay on idle for few tanks just add nitro don't need to let it cold down bis the temp around 80-90 Celsius idle on stand for 3 tank. Use Allen key wrench to turn the pinion screw to release lock after u get the temp to 90 Celsius. Don't force it when it is cold Hope that help.