YS engines break in?
01-29-2014, 07:50 PM
#1
YS engines break in?
I have two engines for warbird racing. I have a YS-115WS and a DZ-70. I plan to run 50% in these engines or more. Should I break in per the instructions or on the higher nitro.
I am leaning to the higher nitro as the flame front and chamber pressure will be different on the higher nitro.
the 115 will be run fly with a 13x14/15 prop and the 70 on a 9x14.
Thoughts?
I am leaning to the higher nitro as the flame front and chamber pressure will be different on the higher nitro.
the 115 will be run fly with a 13x14/15 prop and the 70 on a 9x14.
Thoughts?
01-30-2014, 11:22 AM
#2
Definately, absolutely, for sure, with out a doubt,
BREAK THESE IN ON 20% NITRO WITH RECOMMENDED YS OIL VALUE (20%) OR HELI FUEL. Run around 3-5 tanks depending on tank size thru them. Id run a 1/2 tank on ground really rich, then take to the skies for another 3-5 tanks , rich, as well.
Run a wee bit smaller prop, so you can get RPMS.
BREAK THESE IN ON 20% NITRO WITH RECOMMENDED YS OIL VALUE (20%) OR HELI FUEL. Run around 3-5 tanks depending on tank size thru them. Id run a 1/2 tank on ground really rich, then take to the skies for another 3-5 tanks , rich, as well.
Run a wee bit smaller prop, so you can get RPMS.
01-30-2014, 05:02 PM
#4
Speed,
Just watch those 13x13N props. Make sure it is a newer one. Some of the older ones had a hub that failed at high RPMS (they werent meant to run at the stress speeds us warbird racers put on them running high nitro on such powerful motors). I had a 13x13n explode on a ground run up. It destroyed my $150 Hyde soft mount. Again let me state, It was no fault of APC. These props werent meant to do what warbird racers do to them. Robert at APC generously took the old props and excganged them for the updated props. He didnt have to do this but he runs a top quality company.
If your prop isnt a newer one ( I think about a year and a half maybe) you might think of a less diameter say a 12x12 regular.
10K is a high RPM. I know you are trying to wear the sleeve and piston in for those higher RPM's, just be careful there.
Just watch those 13x13N props. Make sure it is a newer one. Some of the older ones had a hub that failed at high RPMS (they werent meant to run at the stress speeds us warbird racers put on them running high nitro on such powerful motors). I had a 13x13n explode on a ground run up. It destroyed my $150 Hyde soft mount. Again let me state, It was no fault of APC. These props werent meant to do what warbird racers do to them. Robert at APC generously took the old props and excganged them for the updated props. He didnt have to do this but he runs a top quality company.
If your prop isnt a newer one ( I think about a year and a half maybe) you might think of a less diameter say a 12x12 regular.
10K is a high RPM. I know you are trying to wear the sleeve and piston in for those higher RPM's, just be careful there.
02-05-2014, 11:49 PM
#6
There are two schools of thought on the break in for these motors. The first being run a tank on the ground rich and then go right to the fuel and prop that is going to be used and fly (this has been done by some top racers). And then there is the method that I prefer. Using a bit less prop, running rich, fly (after first tank very rich on ground) a gallon through the motor. Then adjust valves and move up in nitro and prop. I like the 14/12n for break in on the 115. Then my next prop and fuel combo mirrors the RPM that I was getting with the prior combo. I like to keep the RPM levels similar to what I was getting during break in. For the 115 I like to target low to mid 10's.
Jimmy Skids
Jimmy Skids
02-06-2014, 07:19 PM
#7
thanks. has any one done any test with different break in where one is low nitro and the with high from the start? the reason most say low nitro is because that is what the MFG says. i know when you add more heat ie: more nitro you are making more power in the engine soyou are building more heat i nthe engine. more heat means different heat cycle and different ear patterns on the engine ring and cylinder. i dont have the money to go out and test 10 engines to see which is best for max power. I am sure it will have plenty of power from the start but always looking for more you know.
Also has anyone done any port work on these engines and the ports are no where near what they should be but hat is where the supercharging helps some. am I going to deep in making more power here?
Maybe i will just break it in on the 50% anyway lol and see what happens a new motor is only 480 bucks.
Also has anyone done any port work on these engines and the ports are no where near what they should be but hat is where the supercharging helps some. am I going to deep in making more power here?
Maybe i will just break it in on the 50% anyway lol and see what happens a new motor is only 480 bucks.
02-06-2014, 07:37 PM
#8
I would say that the oil package is the most important piece of the mix. I perfer Cool Power oil for my motors. I also am not sure of the effect on the motor of nitro. My motors on high nitro are cool also. I believe the heat is more a factor of how the motor is needled and RPM. This is why I shoot for props and nitro combos that run similar RPM. If you keep the motor in the 10k to 10.5k range on the 1.15 it will be happy.
Jimmy Skids
Jimmy Skids
