Why the difference I wonder....

My Brake in procedure is to run 2 tank full of fuel 20% oil no nitro on the ground.
Slowly increasing the RPM .
Mixture 2 1/2 - 3 turns out

Slow idle for 5 minutes then high idle for 5 minutes occasionally increasing power.for 1 minute
I do this until fuel runs out and let engine cool down with fan.

I check the temperature after each run and make sure its below 60 deg C

Then Fly in aircraft with rich needle slowly leaning until I am happy or should I say until engine is happy.
I always check engine temperature after each flight .
I use my own Fuel 30% NITRO 15 % COOL POWER Lv

After the end of the days flying I run the engine with 20% oil no nitro fuel for 5 minutes and drop a few drops of after run.

With this procedure I get around 150 flights before Bearings start to play up

regards